[PATCH 0/2] gitk --color-words

[PATCH 0/2] gitk --color-words

[Thomas Rast]

Miles Bader wrote:
> Junio C Hamano <gitster@pobox.com> writes:
> > How readable can you make this for human consumption while still keeping
> > it machine readable?  The answer could be it already is human readble.
> >
> > Two reasons I ask the above question are that I find the feature quite
> > interesting, and would want to see if it can be also fed to humans, and
> > that the combination of this new option and the existing --color-words is
> > misnamed.
> 
> There's the format used by the "wdiff" program, which is more like
> traditional diff output in that it doesn't use color, but is human
> friendly, and also seems to be somewhat machine-parseable:
> 
>    $ echo 'This is a test' > /tmp/a
>    $ echo 'This is funky test' > /tmp/b
>    $ wdiff /tmp/a /tmp/b
>    This is [-a-] {+funky+} test
> 
> [I say "somewhat" because wdiff itself doesn't appear to escape potentially
> ambiguous content, e.g., if there's actually a "{+" in the file....]

Junio C Hamano wrote:
> If you call this --word-diff, then it would become more clear that
> --color-words perhaps should have been called --word-diff=color or
> something.

Excellent ideas!  I don't have anything to add ;-)

This makes [1/2] a rather new patch though, I moved the whole
prefix/suffix handing further out to accommodate different styles.

There's a little change in [2/2] apart from the obvious option
renaming, too: it interprets --color-words and --word-diff as an
initial setting for the checkbox.


Thomas Rast (2):
  diff: add --word-diff option that generalizes --color-words
  gitk: add the equivalent of diff --color-words

[PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

This teaches the --color-words engine a more general interface that
supports two new modes:

* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
  'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}

* --word-diff=porcelain, which generates an ad-hoc machine readable
  format:
  - each diff unit is prefixed by [-+ ] and terminated by newline as
    in unified diff
  - newlines in the input are output as a line consisting only of a
    tilde '~'

--color-words becomes a synonym for --word-diff=color.  Also adds some
compatibility/convenience options.

Thanks to Junio C Hamano and Miles Bader for good ideas.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 Documentation/diff-options.txt  |   39 +++++++++-
 Documentation/gitattributes.txt |    2 +-
 color.c                         |   28 -------
 color.h                         |    1 -
 diff.c                          |  148 ++++++++++++++++++++++++++++++++++-----
 diff.h                          |   11 +++-
 t/t4034-diff-words.sh           |   70 ++++++++++++++++++
 7 files changed, 245 insertions(+), 54 deletions(-)

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 60e922e..e51fc9a 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -126,11 +126,38 @@ any of those replacements occurred.
 	gives the default to color output.
 	Same as `--color=never`.
 
---color-words[=<regex>]::
-	Show colored word diff, i.e., color words which have changed.
-	By default, words are separated by whitespace.
+--word-diff[=<mode>]::
+	Show a word diff, using the <mode> to delimit changed words.
+	By default, words are delimited by whitespace; see
+	`--word-diff-regex` below.  The <mode> defaults to 'auto', and
+	must be one of:
++
+--
+color::
+	Highlight changed words with colors.  Implies `--color`.
+plain::
+	Show words as `[-removed-]` and `{+added+}`.  Makes no
+	attempts to escape the delimiters if they appear in the input,
+	so the output may be ambiguous.
+porcelain::
+	Use a special line-based format intended for script
+	consumption.  Added/removed/unchanged runs are printed in the
+	usual unified diff format, starting with a `+`/`-`/` `
+	character at the beginning of the line and extending to the
+	end of the line.  Newlines in the input are represented by a
+	tilde `~` on a line of its own.
+auto::
+	'color' if color is enabled, 'plain' otherwise.
+none::
+	Disable word diff again.
+--
+
+--word-diff-regex=<regex>::
+	Use <regex> to decide what a word is, instead of considering
+	runs of non-whitespace to be a word.  Also implies
+	`--word-diff=auto` unless it was already enabled.
 +
-When a <regex> is specified, every non-overlapping match of the
+Every non-overlapping match of the
 <regex> is considered a word.  Anything between these matches is
 considered whitespace and ignored(!) for the purposes of finding
 differences.  You may want to append `|[^[:space:]]` to your regular
@@ -142,6 +169,10 @@ The regex can also be set via a diff driver or configuration option, see
 linkgit:gitattributes[1] or linkgit:git-config[1].  Giving it explicitly
 overrides any diff driver or configuration setting.  Diff drivers
 override configuration settings.
+
+--color-words[=<regex>]::
+	Equivalent to `--word-diff=color` plus (if a regex was
+	specified) `--word-diff-regex=<regex>`.
 endif::git-format-patch[]
 
 --no-renames::
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index d892e64..7554fcd 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -360,7 +360,7 @@ patterns are available:
 Customizing word diff
 ^^^^^^^^^^^^^^^^^^^^^
 
-You can customize the rules that `git diff --color-words` uses to
+You can customize the rules that `git diff --word-diff` uses to
 split words in a line, by specifying an appropriate regular expression
 in the "diff.*.wordRegex" configuration variable.  For example, in TeX
 a backslash followed by a sequence of letters forms a command, but
diff --git a/color.c b/color.c
index bcf4e2c..1b00554 100644
--- a/color.c
+++ b/color.c
@@ -211,31 +211,3 @@ int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 	va_end(args);
 	return r;
 }
-
-/*
- * This function splits the buffer by newlines and colors the lines individually.
- *
- * Returns 0 on success.
- */
-int color_fwrite_lines(FILE *fp, const char *color,
-		size_t count, const char *buf)
-{
-	if (!*color)
-		return fwrite(buf, count, 1, fp) != 1;
-	while (count) {
-		char *p = memchr(buf, '\n', count);
-		if (p != buf && (fputs(color, fp) < 0 ||
-				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
-				fputs(GIT_COLOR_RESET, fp) < 0))
-			return -1;
-		if (!p)
-			return 0;
-		if (fputc('\n', fp) < 0)
-			return -1;
-		count -= p + 1 - buf;
-		buf = p + 1;
-	}
-	return 0;
-}
-
-
diff --git a/color.h b/color.h
index 5c264b0..03ca064 100644
--- a/color.h
+++ b/color.h
@@ -61,6 +61,5 @@
 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...);
 __attribute__((format (printf, 3, 4)))
 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...);
-int color_fwrite_lines(FILE *fp, const char *color, size_t count, const char *buf);
 
 #endif /* COLOR_H */
diff --git a/diff.c b/diff.c
index f5d93e9..dca310e 100644
--- a/diff.c
+++ b/diff.c
@@ -572,16 +572,60 @@ static void diff_words_append(char *line, unsigned long len,
 	buffer->text.ptr[buffer->text.size] = '\0';
 }
 
+struct diff_words_style
+{
+	enum diff_words_type type;
+	int is_color;
+	const char *new_prefix;
+	const char *new_suffix;
+	const char *old_prefix;
+	const char *old_suffix;
+	const char *ctx_prefix;
+	const char *ctx_suffix;
+	const char *newline;
+};
+
+struct diff_words_style diff_words_styles[] = {
+	{ DIFF_WORDS_PORCELAIN, 0, "+", "\n", "-", "\n", " ", "\n", "~\n" },
+	{ DIFF_WORDS_PLAIN, 0, "{+", "+}", "[-", "-]", "", "", "\n" },
+	{ DIFF_WORDS_COLOR, 1, NULL, NULL, NULL, NULL, NULL, NULL, "\n" }
+};
+
 struct diff_words_data {
 	struct diff_words_buffer minus, plus;
 	const char *current_plus;
 	FILE *file;
 	regex_t *word_regex;
+	enum diff_words_type type;
+	struct diff_words_style *style;
 };
 
+static int fn_out_diff_words_write_helper(FILE *fp,
+					  const char *prefix,
+					  const char *suffix,
+					  const char *newline,
+					  size_t count, const char *buf)
+{
+	while (count) {
+		char *p = memchr(buf, '\n', count);
+		if (p != buf && (fputs(prefix, fp) < 0 ||
+				 fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
+				 fputs(suffix, fp) < 0))
+			return -1;
+		if (!p)
+			return 0;
+		if (fputs(newline, fp) < 0)
+			return -1;
+		count -= p + 1 - buf;
+		buf = p + 1;
+	}
+	return 0;
+}
+
 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 {
 	struct diff_words_data *diff_words = priv;
+	struct diff_words_style *style = diff_words->style;
 	int minus_first, minus_len, plus_first, plus_len;
 	const char *minus_begin, *minus_end, *plus_begin, *plus_end;
 
@@ -605,16 +649,20 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 		plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
 
 	if (diff_words->current_plus != plus_begin)
-		fwrite(diff_words->current_plus,
-				plus_begin - diff_words->current_plus, 1,
-				diff_words->file);
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->ctx_prefix, style->ctx_suffix,
+				style->newline,
+				plus_begin - diff_words->current_plus,
+				diff_words->current_plus);
 	if (minus_begin != minus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->old_prefix, style->old_suffix,
+				style->newline,
 				minus_end - minus_begin, minus_begin);
 	if (plus_begin != plus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_NEW),
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->new_prefix, style->new_suffix,
+				style->newline,
 				plus_end - plus_begin, plus_begin);
 
 	diff_words->current_plus = plus_end;
@@ -697,11 +745,13 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	xdemitconf_t xecfg;
 	xdemitcb_t ecb;
 	mmfile_t minus, plus;
+	struct diff_words_style *style = diff_words->style;
 
 	/* special case: only removal */
 	if (!diff_words->plus.text.size) {
-		color_fwrite_lines(diff_words->file,
-			diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+			style->old_prefix, style->old_suffix,
+			style->newline,
 			diff_words->minus.text.size, diff_words->minus.text.ptr);
 		diff_words->minus.text.size = 0;
 		return;
@@ -722,10 +772,11 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	free(plus.ptr);
 	if (diff_words->current_plus != diff_words->plus.text.ptr +
 			diff_words->plus.text.size)
-		fwrite(diff_words->current_plus,
+		fn_out_diff_words_write_helper(diff_words->file,
+			style->ctx_prefix, style->ctx_suffix,
+			style->newline,
 			diff_words->plus.text.ptr + diff_words->plus.text.size
-			- diff_words->current_plus, 1,
-			diff_words->file);
+			- diff_words->current_plus, diff_words->current_plus);
 	diff_words->minus.text.size = diff_words->plus.text.size = 0;
 }
 
@@ -837,6 +888,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 
 	if (len < 1) {
 		emit_line(ecbdata->file, reset, reset, line, len);
+		if (ecbdata->diff_words
+		    && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
+			fputs("~\n", ecbdata->file);
 		return;
 	}
 
@@ -851,9 +905,13 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			return;
 		}
 		diff_words_flush(ecbdata);
-		line++;
-		len--;
-		emit_line(ecbdata->file, plain, reset, line, len);
+		if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
+			emit_line(ecbdata->file, plain, reset, line, len);
+			fputs("~\n", ecbdata->file);
+		} else {
+			/* don't print the prefix character */
+			emit_line(ecbdata->file, plain, reset, line+1, len-1);
+		}
 		return;
 	}
 
@@ -1755,10 +1813,19 @@ static void builtin_diff(const char *name_a,
 			xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 		else if (!prefixcmp(diffopts, "-u"))
 			xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
+		if (o->word_diff) {
+			int i;
+
+			if (o->word_diff == DIFF_WORDS_AUTO) {
+				if (DIFF_OPT_TST(o, COLOR_DIFF))
+					o->word_diff = DIFF_WORDS_COLOR;
+				else
+					o->word_diff = DIFF_WORDS_PLAIN;
+			}
 			ecbdata.diff_words =
 				xcalloc(1, sizeof(struct diff_words_data));
 			ecbdata.diff_words->file = o->file;
+			ecbdata.diff_words->type = o->word_diff;
 			if (!o->word_regex)
 				o->word_regex = userdiff_word_regex(one);
 			if (!o->word_regex)
@@ -1774,10 +1841,27 @@ static void builtin_diff(const char *name_a,
 					die ("Invalid regular expression: %s",
 							o->word_regex);
 			}
+			for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
+				if (o->word_diff == diff_words_styles[i].type) {
+					ecbdata.diff_words->style =
+						&diff_words_styles[i];
+					break;
+				}
+			}
+			if (ecbdata.diff_words->style->is_color) {
+				struct diff_words_style *s
+					= ecbdata.diff_words->style;
+				s->new_prefix = diff_get_color_opt(o, DIFF_FILE_NEW);
+				s->old_prefix = diff_get_color_opt(o, DIFF_FILE_OLD);
+				s->ctx_prefix = diff_get_color_opt(o, DIFF_PLAIN);
+				s->new_suffix = s->old_suffix
+					= diff_get_color_opt(o, DIFF_RESET);
+				s->ctx_suffix = "";
+			}
 		}
 		xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
 			      &xpp, &xecfg, &ecb);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
+		if (o->word_diff)
 			free_diff_words_data(&ecbdata);
 		if (textconv_one)
 			free(mf1.ptr);
@@ -2845,13 +2929,39 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, COLOR_DIFF);
 	else if (!strcmp(arg, "--color-words")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 	}
 	else if (!prefixcmp(arg, "--color-words=")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 		options->word_regex = arg + 14;
 	}
+	else if (!strcmp(arg, "--word-diff")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_AUTO;
+	}
+	else if (!prefixcmp(arg, "--word-diff=")) {
+		const char *type = arg + 12;
+		if (!strcmp(type, "auto"))
+			options->word_diff = DIFF_WORDS_AUTO;
+		else if (!strcmp(type, "plain"))
+			options->word_diff = DIFF_WORDS_PLAIN;
+		else if (!strcmp(type, "color")) {
+			DIFF_OPT_SET(options, COLOR_DIFF);
+			options->word_diff = DIFF_WORDS_COLOR;
+		}
+		else if (!strcmp(type, "porcelain"))
+			options->word_diff = DIFF_WORDS_PORCELAIN;
+		else if (!strcmp(type, "none"))
+			options->word_diff = DIFF_WORDS_NONE;
+		else
+			die("bad --word-diff argument: %s", type);
+	}
+	else if (!prefixcmp(arg, "--word-diff-regex=")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_AUTO;
+		options->word_regex = arg + 18;
+	}
 	else if (!strcmp(arg, "--exit-code"))
 		DIFF_OPT_SET(options, EXIT_WITH_STATUS);
 	else if (!strcmp(arg, "--quiet"))
diff --git a/diff.h b/diff.h
index 6a71013..7c8e3ff 100644
--- a/diff.h
+++ b/diff.h
@@ -54,7 +54,7 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_OPT_FIND_COPIES_HARDER  (1 <<  6)
 #define DIFF_OPT_FOLLOW_RENAMES      (1 <<  7)
 #define DIFF_OPT_COLOR_DIFF          (1 <<  8)
-#define DIFF_OPT_COLOR_DIFF_WORDS    (1 <<  9)
+/* (1 <<  9) unused */
 #define DIFF_OPT_HAS_CHANGES         (1 << 10)
 #define DIFF_OPT_QUICK               (1 << 11)
 #define DIFF_OPT_NO_INDEX            (1 << 12)
@@ -79,6 +79,14 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_XDL_SET(opts, flag)    ((opts)->xdl_opts |= XDF_##flag)
 #define DIFF_XDL_CLR(opts, flag)    ((opts)->xdl_opts &= ~XDF_##flag)
 
+enum diff_words_type {
+	DIFF_WORDS_NONE = 0,
+	DIFF_WORDS_AUTO,
+	DIFF_WORDS_PORCELAIN,
+	DIFF_WORDS_PLAIN,
+	DIFF_WORDS_COLOR
+};
+
 struct diff_options {
 	const char *filter;
 	const char *orderfile;
@@ -108,6 +116,7 @@ struct diff_options {
 	int stat_width;
 	int stat_name_width;
 	const char *word_regex;
+	enum diff_words_type word_diff;
 
 	/* this is set by diffcore for DIFF_FORMAT_PATCH */
 	int found_changes;
diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
index 2e2e103..764368d 100755
--- a/t/t4034-diff-words.sh
+++ b/t/t4034-diff-words.sh
@@ -55,6 +55,72 @@ test_expect_success 'word diff with runs of whitespace' '
 
 '
 
+test_expect_success '--word-diff=color' '
+
+	word_diff --word-diff=color
+
+'
+
+test_expect_success '--color --word-diff=color' '
+
+	word_diff --color --word-diff=auto
+
+'
+
+sed 's/#.*$//' > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+-h(4)
++h(4),hh[44]
+~
+ # significant space
+~
+ a = b + c
+~
+~
++aa = a
+~
+~
++aeff = aeff * ( aaa )
+~
+EOF
+
+test_expect_success '--word-diff=porcelain' '
+
+	word_diff --word-diff=porcelain
+
+'
+
+cat > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+[-h(4)-]{+h(4),hh[44]+}
+
+a = b + c
+
+{+aa = a+}
+
+{+aeff = aeff * ( aaa )+}
+EOF
+
+test_expect_success '--word-diff=plain' '
+
+	word_diff --word-diff=plain
+
+'
+
+test_expect_success '--no-color --word-diff=color' '
+
+	word_diff --no-color --word-diff=auto
+
+'
+
 cat > expect <<\EOF
 <WHITE>diff --git a/pre b/post<RESET>
 <WHITE>index 330b04f..5ed8eff 100644<RESET>
@@ -143,6 +209,10 @@ test_expect_success 'command-line overrides config' '
 	word_diff --color-words="[a-z]+"
 '
 
+test_expect_success 'command-line overrides config: --word-diff-regex' '
+	word_diff --color --word-diff-regex="[a-z]+"
+'
+
 cp expect.non-whitespace-is-word expect
 
 test_expect_success '.gitattributes override config' '
-- 
1.7.0.3.521.ga1e9e

Re: [PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Junio C Hamano]

Thomas Rast <trast@student.ethz.ch> writes:

> This teaches the --color-words engine a more general interface that
> supports two new modes:
>
> * --word-diff=plain, inspired by the 'wdiff' utility (most similar to
>   'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}
>
> * --word-diff=porcelain, which generates an ad-hoc machine readable
>   format:
>   - each diff unit is prefixed by [-+ ] and terminated by newline as
>     in unified diff
>   - newlines in the input are output as a line consisting only of a
>     tilde '~'

Thanks.  This was a fun feature to look at.

I think it is a bug that "git show --word-diff" gives the colored format
output when I have "color.ui" configuration.

Even though I may have "color.ui = auto" in the configuration, I am
telling the command to do a --word-diff, not --color-words, from the
command line, and that should override color.ui settings.

So I think a request for --word-diff that is not --word-diff=color should
never use the --color-words _unless_ there is --color on the command line:

	git show --word-diff
	git show --word-diff=plain
	git show --word-diff=porcelain

All of the above may paint hunk headers and metainfo the usual way when I
have "color.ui" set, but I do not want them to be painting the diff part
like --color-words does.  I am fine if "porcelain" did not to paint the
metainfo, but I see this feature as three different output types of how
word diff is presented, so in that sense, it probably is better to force
scripts to explicitly ask for no-color, i.e.

	git show --no-color --word-diff=porcelain

if they want to read and interpret metainfo.

When the command line asks for color explicitly, then we should see the
good old --color-words:

	git show --color-words
	git show --word-diff=color

I am not sure what the following two should do.  One could argue that
these default to --color-words; or --color should apply only to the
coloring of metainfo but not the diff part:

        git show --color --word-diff
        git show --word-diff --color

I am slightly in favor of doing the same as --color-words, but people may
have different opinions.

The following of course should show the plain word diff but the metainfo
and friends colored:

        git show --word-diff=plain --color
        git show --color --word-diff=plain

It might be just the matter of defaulting --word-diff without "=<type>"
not to "auto" but to "plain".  I haven't looked at the code closely yet.

Re: [PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

Junio C Hamano wrote:
> 
> I think it is a bug that "git show --word-diff" gives the colored format
> output when I have "color.ui" configuration.
> 
> Even though I may have "color.ui = auto" in the configuration, I am
> telling the command to do a --word-diff, not --color-words, from the
> command line, and that should override color.ui settings.

I don't really see why the user would forfeit the convenience and
readability of a color-words diff when the terminal supports colors.
Granted, this is probably the first instance where the colors actually
change the output format instead of just making easier to read, but
still?

But:

> It might be just the matter of defaulting --word-diff without "=<type>"
> not to "auto" but to "plain".  I haven't looked at the code closely yet.

Yes.

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

Re: [PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Junio C Hamano]

Thomas Rast <trast@student.ethz.ch> writes:

>> I think it is a bug that "git show --word-diff" gives the colored format
>> output when I have "color.ui" configuration.
>> 
>> Even though I may have "color.ui = auto" in the configuration, I am
>> telling the command to do a --word-diff, not --color-words, from the
>> command line, and that should override color.ui settings.
>
> I don't really see why the user would forfeit the convenience and
> readability of a color-words diff when the terminal supports colors.

There is one difference between other uses of colors and color-words, but
I can imagine that ordinary people may not have even realized nor thought
about it.

To people who are somewhat but not completely color-challenged (like
myself), it still helps to paint hunk headers in a color that is different
from the body text to make the boundary of each hunk more visible.  Even
without the perception of exact color/hue, the contrast alone helps in
that case.

The body of the diff is painted in deleted and added colors; the color is
used only as a way to additionally enhance the output, while still keeping
the plus/minus/SP at the leftmost column.  Even to somebody who is
completely color challenged, the necessary information is still there.

Compare --color-words with these.  The output uses color as the _only_ way
to say which words appear before and after.  The contrast among the three
colors used for the plain body, deleted and added text may still help, or
it may not, to a partially color challenged person.

I also happen to see "--word-diff=color" more as just a customization to
the "plain" output formatting to say "use these byte sequences that happen
to be ANSI color codes, instead of '{+', '+}', etc." than as a part of
what the ui.color switch wants to specify, which is "are various parts of
the output colored to further help distinguishing them visually?"

So color me somewhat biased, but there is a case where the suggestion in
the message you are responding to makes a difference.

I also think --color --word-diff=plain could show "{+new+}" in green and
"[-old-]" in red and that may make things more consistent.

Re: [PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Miles Bader]

On Tue, Apr 6, 2010 at 3:46 AM, Junio C Hamano <gitster@pobox.com> wrote:
> I also think --color --word-diff=plain could show "{+new+}" in green and
> "[-old-]" in red and that may make things more consistent.

I agree.

For some reason, even though I can see the red and green well enough,
I find the current --color-words output hard to parse.
The use of _only_ color to distinguish old/new somehow doesn't jive
with my brain...

I find _highlighting_ using color very useful, but I think using
syntax and color together is better than using just color.

-Miles

-- 
Do not taunt Happy Fun Ball.

[PATCH v3 0/2] gitk --color-words

[Thomas Rast]

During development an unrelated gitk diff parsing bug hit me, which is
the new 2/3.  I think it should go in maint if the patch turns out to
be correct, but I'd like to have an ACK from Jens first.

Junio C Hamano wrote:
> I also think --color --word-diff=plain could show "{+new+}" in green and
> "[-old-]" in red and that may make things more consistent.

So here's a patch that does that.  I may be overdoing the "generic
diff style" code a bit, but it makes for slightly nicer code.

I similarly extended the support in gitk to have two different modes.
My use of the dropdown is again sheer voodoo and works merely by
accident...

I also taught gitk to not show the option and not parse the
command-line options unless the git version is at least v1.7.2, which
I expect will be the version that has the underlying diff support.

BTW:

Miles Bader wrote:
> For some reason, even though I can see the red and green well enough,
> I find the current --color-words output hard to parse.
> The use of _only_ color to distinguish old/new somehow doesn't jive
> with my brain...

I set my diff colors to bold red/blue which makes the changed words
very visible even in light conditions where green is very hard to tell
from black (sitting outside in the sun or so).

> I find _highlighting_ using color very useful, but I think using
> syntax and color together is better than using just color.

Well, I for one find the extra markup *very* confusing because I need
to mentally untangle it from the actual content...


Thomas Rast (3):
  diff: add --word-diff option that generalizes --color-words
  gitk: do not parse "  >" context as submodule change
  gitk: add the equivalent of diff --color-words

[PATCH v3 1/3] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

This teaches the --color-words engine a more general interface that
supports two new modes:

* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
  'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}

* --word-diff=porcelain, which generates an ad-hoc machine readable
  format:
  - each diff unit is prefixed by [-+ ] and terminated by newline as
    in unified diff
  - newlines in the input are output as a line consisting only of a
    tilde '~'

Both of these formats still support color if it is enabled, using it
to highlight the differences.  --color-words becomes a synonym for
--word-diff=color, which is the color-only format.  Also adds some
compatibility/convenience options.

Thanks to Junio C Hamano and Miles Bader for good ideas.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 Documentation/diff-options.txt  |   40 +++++++++-
 Documentation/gitattributes.txt |    2 +-
 color.c                         |   28 -------
 color.h                         |    1 -
 diff.c                          |  154 ++++++++++++++++++++++++++++++++++-----
 diff.h                          |   10 ++-
 t/t4034-diff-words.sh           |  122 +++++++++++++++++++++++++++++++
 7 files changed, 303 insertions(+), 54 deletions(-)

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 60e922e..a616ca5 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -126,11 +126,39 @@ any of those replacements occurred.
 	gives the default to color output.
 	Same as `--color=never`.
 
---color-words[=<regex>]::
-	Show colored word diff, i.e., color words which have changed.
-	By default, words are separated by whitespace.
+--word-diff[=<mode>]::
+	Show a word diff, using the <mode> to delimit changed words.
+	By default, words are delimited by whitespace; see
+	`--word-diff-regex` below.  The <mode> defaults to 'plain', and
+	must be one of:
++
+--
+color::
+	Highlight changed words using only colors.  Implies `--color`.
+plain::
+	Show words as `[-removed-]` and `{+added+}`.  Makes no
+	attempts to escape the delimiters if they appear in the input,
+	so the output may be ambiguous.
+porcelain::
+	Use a special line-based format intended for script
+	consumption.  Added/removed/unchanged runs are printed in the
+	usual unified diff format, starting with a `+`/`-`/` `
+	character at the beginning of the line and extending to the
+	end of the line.  Newlines in the input are represented by a
+	tilde `~` on a line of its own.
+none::
+	Disable word diff again.
+--
++
+Note that despite the name of the first mode, color is used to
+highlight the changed parts in all modes if enabled.
+
+--word-diff-regex=<regex>::
+	Use <regex> to decide what a word is, instead of considering
+	runs of non-whitespace to be a word.  Also implies
+	`--word-diff` unless it was already enabled.
 +
-When a <regex> is specified, every non-overlapping match of the
+Every non-overlapping match of the
 <regex> is considered a word.  Anything between these matches is
 considered whitespace and ignored(!) for the purposes of finding
 differences.  You may want to append `|[^[:space:]]` to your regular
@@ -142,6 +170,10 @@ The regex can also be set via a diff driver or configuration option, see
 linkgit:gitattributes[1] or linkgit:git-config[1].  Giving it explicitly
 overrides any diff driver or configuration setting.  Diff drivers
 override configuration settings.
+
+--color-words[=<regex>]::
+	Equivalent to `--word-diff=color` plus (if a regex was
+	specified) `--word-diff-regex=<regex>`.
 endif::git-format-patch[]
 
 --no-renames::
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index a8500d1..0523a57 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -360,7 +360,7 @@ patterns are available:
 Customizing word diff
 ^^^^^^^^^^^^^^^^^^^^^
 
-You can customize the rules that `git diff --color-words` uses to
+You can customize the rules that `git diff --word-diff` uses to
 split words in a line, by specifying an appropriate regular expression
 in the "diff.*.wordRegex" configuration variable.  For example, in TeX
 a backslash followed by a sequence of letters forms a command, but
diff --git a/color.c b/color.c
index bcf4e2c..1b00554 100644
--- a/color.c
+++ b/color.c
@@ -211,31 +211,3 @@ int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 	va_end(args);
 	return r;
 }
-
-/*
- * This function splits the buffer by newlines and colors the lines individually.
- *
- * Returns 0 on success.
- */
-int color_fwrite_lines(FILE *fp, const char *color,
-		size_t count, const char *buf)
-{
-	if (!*color)
-		return fwrite(buf, count, 1, fp) != 1;
-	while (count) {
-		char *p = memchr(buf, '\n', count);
-		if (p != buf && (fputs(color, fp) < 0 ||
-				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
-				fputs(GIT_COLOR_RESET, fp) < 0))
-			return -1;
-		if (!p)
-			return 0;
-		if (fputc('\n', fp) < 0)
-			return -1;
-		count -= p + 1 - buf;
-		buf = p + 1;
-	}
-	return 0;
-}
-
-
diff --git a/color.h b/color.h
index 5c264b0..03ca064 100644
--- a/color.h
+++ b/color.h
@@ -61,6 +61,5 @@
 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...);
 __attribute__((format (printf, 3, 4)))
 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...);
-int color_fwrite_lines(FILE *fp, const char *color, size_t count, const char *buf);
 
 #endif /* COLOR_H */
diff --git a/diff.c b/diff.c
index 7effdac..ca054d4 100644
--- a/diff.c
+++ b/diff.c
@@ -560,16 +560,83 @@ static void diff_words_append(char *line, unsigned long len,
 	buffer->text.ptr[buffer->text.size] = '\0';
 }
 
+struct diff_words_style_elem
+{
+	const char *prefix;
+	const char *suffix;
+	const char *color; /* NULL; filled in by the setup code if
+			    * color is enabled */
+};
+
+struct diff_words_style
+{
+	enum diff_words_type type;
+	struct diff_words_style_elem new, old, ctx;
+	const char *newline;
+};
+
+struct diff_words_style diff_words_styles[] = {
+	{ DIFF_WORDS_PORCELAIN,
+	  {"+", "\n", NULL},
+	  {"-", "\n", NULL},
+	  {" ", "\n", NULL},
+	  "~\n"
+	},
+	{ DIFF_WORDS_PLAIN,
+	  {"{+", "+}", NULL},
+	  {"[-", "-]", NULL},
+	  {"", "", NULL},
+	  "\n"
+	},
+	{ DIFF_WORDS_COLOR,
+	  {"", "", NULL},
+	  {"", "", NULL},
+	  {"", "", NULL},
+	  "\n"
+	}
+};
+
 struct diff_words_data {
 	struct diff_words_buffer minus, plus;
 	const char *current_plus;
 	FILE *file;
 	regex_t *word_regex;
+	enum diff_words_type type;
+	struct diff_words_style *style;
 };
 
+static int fn_out_diff_words_write_helper(FILE *fp,
+					  struct diff_words_style_elem st_el,
+					  const char *newline,
+					  size_t count, const char *buf)
+{
+	while (count) {
+		char *p = memchr(buf, '\n', count);
+		if (p != buf) {
+			if (st_el.color && fputs(st_el.color, fp) < 0)
+				return -1;
+			if (fputs(st_el.prefix, fp) < 0 ||
+			    fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
+			    fputs(st_el.suffix, fp) < 0)
+				return -1;
+			if (st_el.color && strlen(st_el.color)
+			    && fputs(GIT_COLOR_RESET, fp) < 0)
+				return -1;
+		}
+		if (!p)
+			return 0;
+		if (fputs(newline, fp) < 0)
+			return -1;
+		count -= p + 1 - buf;
+		buf = p + 1;
+	}
+	return 0;
+}
+
 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 {
 	struct diff_words_data *diff_words = priv;
+	struct diff_words_style *style = diff_words->style;
 	int minus_first, minus_len, plus_first, plus_len;
 	const char *minus_begin, *minus_end, *plus_begin, *plus_end;
 
@@ -593,16 +660,17 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 		plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
 
 	if (diff_words->current_plus != plus_begin)
-		fwrite(diff_words->current_plus,
-				plus_begin - diff_words->current_plus, 1,
-				diff_words->file);
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->ctx, style->newline,
+				plus_begin - diff_words->current_plus,
+				diff_words->current_plus);
 	if (minus_begin != minus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->old, style->newline,
 				minus_end - minus_begin, minus_begin);
 	if (plus_begin != plus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_NEW),
+		fn_out_diff_words_write_helper(diff_words->file,
+				style->new, style->newline,
 				plus_end - plus_begin, plus_begin);
 
 	diff_words->current_plus = plus_end;
@@ -685,11 +753,12 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	xdemitconf_t xecfg;
 	xdemitcb_t ecb;
 	mmfile_t minus, plus;
+	struct diff_words_style *style = diff_words->style;
 
 	/* special case: only removal */
 	if (!diff_words->plus.text.size) {
-		color_fwrite_lines(diff_words->file,
-			diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+			style->old, style->newline,
 			diff_words->minus.text.size, diff_words->minus.text.ptr);
 		diff_words->minus.text.size = 0;
 		return;
@@ -710,10 +779,10 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	free(plus.ptr);
 	if (diff_words->current_plus != diff_words->plus.text.ptr +
 			diff_words->plus.text.size)
-		fwrite(diff_words->current_plus,
+		fn_out_diff_words_write_helper(diff_words->file,
+			style->ctx, style->newline,
 			diff_words->plus.text.ptr + diff_words->plus.text.size
-			- diff_words->current_plus, 1,
-			diff_words->file);
+			- diff_words->current_plus, diff_words->current_plus);
 	diff_words->minus.text.size = diff_words->plus.text.size = 0;
 }
 
@@ -825,6 +894,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 
 	if (len < 1) {
 		emit_line(ecbdata->file, reset, reset, line, len);
+		if (ecbdata->diff_words
+		    && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
+			fputs("~\n", ecbdata->file);
 		return;
 	}
 
@@ -839,9 +911,13 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			return;
 		}
 		diff_words_flush(ecbdata);
-		line++;
-		len--;
-		emit_line(ecbdata->file, plain, reset, line, len);
+		if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
+			emit_line(ecbdata->file, plain, reset, line, len);
+			fputs("~\n", ecbdata->file);
+		} else {
+			/* don't print the prefix character */
+			emit_line(ecbdata->file, plain, reset, line+1, len-1);
+		}
 		return;
 	}
 
@@ -1739,10 +1815,13 @@ static void builtin_diff(const char *name_a,
 			xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 		else if (!prefixcmp(diffopts, "-u"))
 			xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
+		if (o->word_diff) {
+			int i;
+
 			ecbdata.diff_words =
 				xcalloc(1, sizeof(struct diff_words_data));
 			ecbdata.diff_words->file = o->file;
+			ecbdata.diff_words->type = o->word_diff;
 			if (!o->word_regex)
 				o->word_regex = userdiff_word_regex(one);
 			if (!o->word_regex)
@@ -1758,10 +1837,23 @@ static void builtin_diff(const char *name_a,
 					die ("Invalid regular expression: %s",
 							o->word_regex);
 			}
+			for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
+				if (o->word_diff == diff_words_styles[i].type) {
+					ecbdata.diff_words->style =
+						&diff_words_styles[i];
+					break;
+				}
+			}
+			if (DIFF_OPT_TST(o, COLOR_DIFF)) {
+				struct diff_words_style *st = ecbdata.diff_words->style;
+				st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
+				st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
+				st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
+			}
 		}
 		xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
 			      &xpp, &xecfg, &ecb);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
+		if (o->word_diff)
 			free_diff_words_data(&ecbdata);
 		if (textconv_one)
 			free(mf1.ptr);
@@ -2830,13 +2922,37 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, COLOR_DIFF);
 	else if (!strcmp(arg, "--color-words")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 	}
 	else if (!prefixcmp(arg, "--color-words=")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 		options->word_regex = arg + 14;
 	}
+	else if (!strcmp(arg, "--word-diff")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+	}
+	else if (!prefixcmp(arg, "--word-diff=")) {
+		const char *type = arg + 12;
+		if (!strcmp(type, "plain"))
+			options->word_diff = DIFF_WORDS_PLAIN;
+		else if (!strcmp(type, "color")) {
+			DIFF_OPT_SET(options, COLOR_DIFF);
+			options->word_diff = DIFF_WORDS_COLOR;
+		}
+		else if (!strcmp(type, "porcelain"))
+			options->word_diff = DIFF_WORDS_PORCELAIN;
+		else if (!strcmp(type, "none"))
+			options->word_diff = DIFF_WORDS_NONE;
+		else
+			die("bad --word-diff argument: %s", type);
+	}
+	else if (!prefixcmp(arg, "--word-diff-regex=")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+		options->word_regex = arg + 18;
+	}
 	else if (!strcmp(arg, "--exit-code"))
 		DIFF_OPT_SET(options, EXIT_WITH_STATUS);
 	else if (!strcmp(arg, "--quiet"))
diff --git a/diff.h b/diff.h
index 6a71013..9ace08c 100644
--- a/diff.h
+++ b/diff.h
@@ -54,7 +54,7 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_OPT_FIND_COPIES_HARDER  (1 <<  6)
 #define DIFF_OPT_FOLLOW_RENAMES      (1 <<  7)
 #define DIFF_OPT_COLOR_DIFF          (1 <<  8)
-#define DIFF_OPT_COLOR_DIFF_WORDS    (1 <<  9)
+/* (1 <<  9) unused */
 #define DIFF_OPT_HAS_CHANGES         (1 << 10)
 #define DIFF_OPT_QUICK               (1 << 11)
 #define DIFF_OPT_NO_INDEX            (1 << 12)
@@ -79,6 +79,13 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_XDL_SET(opts, flag)    ((opts)->xdl_opts |= XDF_##flag)
 #define DIFF_XDL_CLR(opts, flag)    ((opts)->xdl_opts &= ~XDF_##flag)
 
+enum diff_words_type {
+	DIFF_WORDS_NONE = 0,
+	DIFF_WORDS_PORCELAIN,
+	DIFF_WORDS_PLAIN,
+	DIFF_WORDS_COLOR
+};
+
 struct diff_options {
 	const char *filter;
 	const char *orderfile;
@@ -108,6 +115,7 @@ struct diff_options {
 	int stat_width;
 	int stat_name_width;
 	const char *word_regex;
+	enum diff_words_type word_diff;
 
 	/* this is set by diffcore for DIFF_FORMAT_PATCH */
 	int found_changes;
diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
index 2e2e103..6f7548c 100755
--- a/t/t4034-diff-words.sh
+++ b/t/t4034-diff-words.sh
@@ -55,6 +55,93 @@ test_expect_success 'word diff with runs of whitespace' '
 
 '
 
+test_expect_success '--word-diff=color' '
+
+	word_diff --word-diff=color
+
+'
+
+test_expect_success '--color --word-diff=color' '
+
+	word_diff --color --word-diff=color
+
+'
+
+sed 's/#.*$//' > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+-h(4)
++h(4),hh[44]
+~
+ # significant space
+~
+ a = b + c
+~
+~
++aa = a
+~
+~
++aeff = aeff * ( aaa )
+~
+EOF
+
+test_expect_success '--word-diff=porcelain' '
+
+	word_diff --word-diff=porcelain
+
+'
+
+cat > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+[-h(4)-]{+h(4),hh[44]+}
+
+a = b + c
+
+{+aa = a+}
+
+{+aeff = aeff * ( aaa )+}
+EOF
+
+test_expect_success '--word-diff=plain' '
+
+	word_diff --word-diff=plain
+
+'
+
+test_expect_success '--word-diff=plain --no-color' '
+
+	word_diff --word-diff=plain --no-color
+
+'
+
+cat > expect <<EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+<RED>[-h(4)-]<RESET><GREEN>{+h(4),hh[44]+}<RESET>
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa )+}<RESET>
+EOF
+
+test_expect_success '--word-diff=plain --color' '
+
+	word_diff --word-diff=plain --color
+
+'
+
 cat > expect <<\EOF
 <WHITE>diff --git a/pre b/post<RESET>
 <WHITE>index 330b04f..5ed8eff 100644<RESET>
@@ -143,6 +230,25 @@ test_expect_success 'command-line overrides config' '
 	word_diff --color-words="[a-z]+"
 '
 
+cat > expect <<\EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+h(4),<GREEN>{+hh+}<RESET>[44]
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa+}<RESET> )
+EOF
+
+test_expect_success 'command-line overrides config: --word-diff-regex' '
+	word_diff --color --word-diff-regex="[a-z]+"
+'
+
 cp expect.non-whitespace-is-word expect
 
 test_expect_success '.gitattributes override config' '
@@ -209,4 +315,20 @@ test_expect_success 'test when words are only removed at the end' '
 
 '
 
+cat > expect <<\EOF
+diff --git a/pre b/post
+index 289cb9d..2d06f37 100644
+--- a/pre
++++ b/post
+@@ -1 +1 @@
+-(:
++(
+EOF
+
+test_expect_success '--word-diff=none' '
+
+	word_diff --word-diff=plain --word-diff=none
+
+'
+
 test_done
-- 
1.7.1.rc0.262.gff1a3

Re: [PATCH v3 1/3] diff: add --word-diff option that generalizes --color-words

[Junio C Hamano]

Thomas Rast <trast@student.ethz.ch> writes:

> diff --git a/diff.c b/diff.c
> index 7effdac..ca054d4 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -560,16 +560,83 @@ static void diff_words_append(char *line, unsigned long len,
>  	buffer->text.ptr[buffer->text.size] = '\0';
>  }
>  
> +struct diff_words_style_elem
> +{
> +	const char *prefix;
> +	const char *suffix;
> +	const char *color; /* NULL; filled in by the setup code if
> +			    * color is enabled */
> +};

The reader makes a mental note that this is a 12- to 24-byte structure...

> +struct diff_words_style
> +{
> +	enum diff_words_type type;
> +	struct diff_words_style_elem new, old, ctx;
> +	const char *newline;
> +};
> +
> +struct diff_words_style diff_words_styles[] = {
> +	{ DIFF_WORDS_PORCELAIN,
> +	  {"+", "\n", NULL},
> +	  {"-", "\n", NULL},
> +	  {" ", "\n", NULL},
> +	  "~\n"
> +	},
> +	{ DIFF_WORDS_PLAIN,
> +	  {"{+", "+}", NULL},
> +	  {"[-", "-]", NULL},
> +	  {"", "", NULL},
> +	  "\n"
> +	},
> +	{ DIFF_WORDS_COLOR,
> +	  {"", "", NULL},
> +	  {"", "", NULL},
> +	  {"", "", NULL},
> +	  "\n"
> +	}
> +};

Beautiful.

The style might be a bit iffy.  Shouldn't an opening "{", unless closed on
the same line with a matching "}", stand on its own line?

> +static int fn_out_diff_words_write_helper(FILE *fp,
> +					  struct diff_words_style_elem st_el,

Do you need to pass this by value?

> +					  const char *newline,
> +					  size_t count, const char *buf)
> +{
> +	while (count) {
> +		char *p = memchr(buf, '\n', count);
> +		if (p != buf) {
> +			if (st_el.color && fputs(st_el.color, fp) < 0)
> +				return -1;
> +			if (fputs(st_el.prefix, fp) < 0 ||
> +			    fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
> +			    fputs(st_el.suffix, fp) < 0)
> +				return -1;
> +			if (st_el.color && strlen(st_el.color)

I would avoid strlen() only for boolean result here---the compilers may
not be as clever as you are.

	if (st_elp->color && *st_elp->color

Re: [PATCH v3 1/3] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

Junio C Hamano wrote:
> Thomas Rast <trast@student.ethz.ch> writes:
[...]
> > +	{ DIFF_WORDS_COLOR,
> > +	  {"", "", NULL},
> > +	  {"", "", NULL},
> > +	  {"", "", NULL},
> > +	  "\n"
> > +	}
> > +};
> 
> Beautiful.
> 
> The style might be a bit iffy.  Shouldn't an opening "{", unless closed on
> the same line with a matching "}", stand on its own line?

Perhaps.  OTOH I just noticed I could also drop the NULL (and let the
implicit 0-padding take over) which makes every style fit on a single
line.  That should make it a bit easier to read.

> > +static int fn_out_diff_words_write_helper(FILE *fp,
> > +					  struct diff_words_style_elem st_el,
> 
> Do you need to pass this by value?

No, thanks for catching this.

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

[PATCH v4 0/3] git-diff --word-diff/gitk --color-words

[Thomas Rast]

This merely addresses Junio's comments on 1/3 of the last round, since
I haven't heard anything about the gitk patches.


Thomas Rast (3):
  diff: add --word-diff option that generalizes --color-words
  gitk: do not parse "  >" context as submodule change
  gitk: add the equivalent of diff --color-words

[PATCH v4 1/3] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

This teaches the --color-words engine a more general interface that
supports two new modes:

* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
  'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}

* --word-diff=porcelain, which generates an ad-hoc machine readable
  format:
  - each diff unit is prefixed by [-+ ] and terminated by newline as
    in unified diff
  - newlines in the input are output as a line consisting only of a
    tilde '~'

Both of these formats still support color if it is enabled, using it
to highlight the differences.  --color-words becomes a synonym for
--word-diff=color, which is the color-only format.  Also adds some
compatibility/convenience options.

Thanks to Junio C Hamano and Miles Bader for good ideas.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 Documentation/diff-options.txt  |   40 ++++++++++-
 Documentation/gitattributes.txt |    2 +-
 color.c                         |   28 --------
 color.h                         |    1 -
 diff.c                          |  139 +++++++++++++++++++++++++++++++++-----
 diff.h                          |   10 +++-
 t/t4034-diff-words.sh           |  122 ++++++++++++++++++++++++++++++++++
 7 files changed, 288 insertions(+), 54 deletions(-)

diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index 60e922e..a616ca5 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -126,11 +126,39 @@ any of those replacements occurred.
 	gives the default to color output.
 	Same as `--color=never`.
 
---color-words[=<regex>]::
-	Show colored word diff, i.e., color words which have changed.
-	By default, words are separated by whitespace.
+--word-diff[=<mode>]::
+	Show a word diff, using the <mode> to delimit changed words.
+	By default, words are delimited by whitespace; see
+	`--word-diff-regex` below.  The <mode> defaults to 'plain', and
+	must be one of:
++
+--
+color::
+	Highlight changed words using only colors.  Implies `--color`.
+plain::
+	Show words as `[-removed-]` and `{+added+}`.  Makes no
+	attempts to escape the delimiters if they appear in the input,
+	so the output may be ambiguous.
+porcelain::
+	Use a special line-based format intended for script
+	consumption.  Added/removed/unchanged runs are printed in the
+	usual unified diff format, starting with a `+`/`-`/` `
+	character at the beginning of the line and extending to the
+	end of the line.  Newlines in the input are represented by a
+	tilde `~` on a line of its own.
+none::
+	Disable word diff again.
+--
++
+Note that despite the name of the first mode, color is used to
+highlight the changed parts in all modes if enabled.
+
+--word-diff-regex=<regex>::
+	Use <regex> to decide what a word is, instead of considering
+	runs of non-whitespace to be a word.  Also implies
+	`--word-diff` unless it was already enabled.
 +
-When a <regex> is specified, every non-overlapping match of the
+Every non-overlapping match of the
 <regex> is considered a word.  Anything between these matches is
 considered whitespace and ignored(!) for the purposes of finding
 differences.  You may want to append `|[^[:space:]]` to your regular
@@ -142,6 +170,10 @@ The regex can also be set via a diff driver or configuration option, see
 linkgit:gitattributes[1] or linkgit:git-config[1].  Giving it explicitly
 overrides any diff driver or configuration setting.  Diff drivers
 override configuration settings.
+
+--color-words[=<regex>]::
+	Equivalent to `--word-diff=color` plus (if a regex was
+	specified) `--word-diff-regex=<regex>`.
 endif::git-format-patch[]
 
 --no-renames::
diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index a8500d1..0523a57 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -360,7 +360,7 @@ patterns are available:
 Customizing word diff
 ^^^^^^^^^^^^^^^^^^^^^
 
-You can customize the rules that `git diff --color-words` uses to
+You can customize the rules that `git diff --word-diff` uses to
 split words in a line, by specifying an appropriate regular expression
 in the "diff.*.wordRegex" configuration variable.  For example, in TeX
 a backslash followed by a sequence of letters forms a command, but
diff --git a/color.c b/color.c
index bcf4e2c..1b00554 100644
--- a/color.c
+++ b/color.c
@@ -211,31 +211,3 @@ int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
 	va_end(args);
 	return r;
 }
-
-/*
- * This function splits the buffer by newlines and colors the lines individually.
- *
- * Returns 0 on success.
- */
-int color_fwrite_lines(FILE *fp, const char *color,
-		size_t count, const char *buf)
-{
-	if (!*color)
-		return fwrite(buf, count, 1, fp) != 1;
-	while (count) {
-		char *p = memchr(buf, '\n', count);
-		if (p != buf && (fputs(color, fp) < 0 ||
-				fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
-				fputs(GIT_COLOR_RESET, fp) < 0))
-			return -1;
-		if (!p)
-			return 0;
-		if (fputc('\n', fp) < 0)
-			return -1;
-		count -= p + 1 - buf;
-		buf = p + 1;
-	}
-	return 0;
-}
-
-
diff --git a/color.h b/color.h
index 5c264b0..03ca064 100644
--- a/color.h
+++ b/color.h
@@ -61,6 +61,5 @@
 int color_fprintf(FILE *fp, const char *color, const char *fmt, ...);
 __attribute__((format (printf, 3, 4)))
 int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...);
-int color_fwrite_lines(FILE *fp, const char *color, size_t count, const char *buf);
 
 #endif /* COLOR_H */
diff --git a/diff.c b/diff.c
index 7effdac..f587b83 100644
--- a/diff.c
+++ b/diff.c
@@ -560,16 +560,68 @@ static void diff_words_append(char *line, unsigned long len,
 	buffer->text.ptr[buffer->text.size] = '\0';
 }
 
+struct diff_words_style_elem
+{
+	const char *prefix;
+	const char *suffix;
+	const char *color; /* NULL; filled in by the setup code if
+			    * color is enabled */
+};
+
+struct diff_words_style
+{
+	enum diff_words_type type;
+	struct diff_words_style_elem new, old, ctx;
+	const char *newline;
+};
+
+struct diff_words_style diff_words_styles[] = {
+	{ DIFF_WORDS_PORCELAIN, {"+", "\n"}, {"-", "\n"}, {" ", "\n"}, "~\n" },
+	{ DIFF_WORDS_PLAIN, {"{+", "+}"}, {"[-", "-]"}, {"", ""}, "\n" },
+	{ DIFF_WORDS_COLOR, {"", ""}, {"", ""}, {"", ""}, "\n" }
+};
+
 struct diff_words_data {
 	struct diff_words_buffer minus, plus;
 	const char *current_plus;
 	FILE *file;
 	regex_t *word_regex;
+	enum diff_words_type type;
+	struct diff_words_style *style;
 };
 
+static int fn_out_diff_words_write_helper(FILE *fp,
+					  struct diff_words_style_elem *st_el,
+					  const char *newline,
+					  size_t count, const char *buf)
+{
+	while (count) {
+		char *p = memchr(buf, '\n', count);
+		if (p != buf) {
+			if (st_el->color && fputs(st_el->color, fp) < 0)
+				return -1;
+			if (fputs(st_el->prefix, fp) < 0 ||
+			    fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
+			    fputs(st_el->suffix, fp) < 0)
+				return -1;
+			if (st_el->color && *st_el->color
+			    && fputs(GIT_COLOR_RESET, fp) < 0)
+				return -1;
+		}
+		if (!p)
+			return 0;
+		if (fputs(newline, fp) < 0)
+			return -1;
+		count -= p + 1 - buf;
+		buf = p + 1;
+	}
+	return 0;
+}
+
 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 {
 	struct diff_words_data *diff_words = priv;
+	struct diff_words_style *style = diff_words->style;
 	int minus_first, minus_len, plus_first, plus_len;
 	const char *minus_begin, *minus_end, *plus_begin, *plus_end;
 
@@ -593,16 +645,17 @@ static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 		plus_begin = plus_end = diff_words->plus.orig[plus_first].end;
 
 	if (diff_words->current_plus != plus_begin)
-		fwrite(diff_words->current_plus,
-				plus_begin - diff_words->current_plus, 1,
-				diff_words->file);
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->ctx, style->newline,
+				plus_begin - diff_words->current_plus,
+				diff_words->current_plus);
 	if (minus_begin != minus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->old, style->newline,
 				minus_end - minus_begin, minus_begin);
 	if (plus_begin != plus_end)
-		color_fwrite_lines(diff_words->file,
-				diff_get_color(1, DIFF_FILE_NEW),
+		fn_out_diff_words_write_helper(diff_words->file,
+				&style->new, style->newline,
 				plus_end - plus_begin, plus_begin);
 
 	diff_words->current_plus = plus_end;
@@ -685,11 +738,12 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	xdemitconf_t xecfg;
 	xdemitcb_t ecb;
 	mmfile_t minus, plus;
+	struct diff_words_style *style = diff_words->style;
 
 	/* special case: only removal */
 	if (!diff_words->plus.text.size) {
-		color_fwrite_lines(diff_words->file,
-			diff_get_color(1, DIFF_FILE_OLD),
+		fn_out_diff_words_write_helper(diff_words->file,
+			&style->old, style->newline,
 			diff_words->minus.text.size, diff_words->minus.text.ptr);
 		diff_words->minus.text.size = 0;
 		return;
@@ -710,10 +764,10 @@ static void diff_words_show(struct diff_words_data *diff_words)
 	free(plus.ptr);
 	if (diff_words->current_plus != diff_words->plus.text.ptr +
 			diff_words->plus.text.size)
-		fwrite(diff_words->current_plus,
+		fn_out_diff_words_write_helper(diff_words->file,
+			&style->ctx, style->newline,
 			diff_words->plus.text.ptr + diff_words->plus.text.size
-			- diff_words->current_plus, 1,
-			diff_words->file);
+			- diff_words->current_plus, diff_words->current_plus);
 	diff_words->minus.text.size = diff_words->plus.text.size = 0;
 }
 
@@ -825,6 +879,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 
 	if (len < 1) {
 		emit_line(ecbdata->file, reset, reset, line, len);
+		if (ecbdata->diff_words
+		    && ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN)
+			fputs("~\n", ecbdata->file);
 		return;
 	}
 
@@ -839,9 +896,13 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			return;
 		}
 		diff_words_flush(ecbdata);
-		line++;
-		len--;
-		emit_line(ecbdata->file, plain, reset, line, len);
+		if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
+			emit_line(ecbdata->file, plain, reset, line, len);
+			fputs("~\n", ecbdata->file);
+		} else {
+			/* don't print the prefix character */
+			emit_line(ecbdata->file, plain, reset, line+1, len-1);
+		}
 		return;
 	}
 
@@ -1739,10 +1800,13 @@ static void builtin_diff(const char *name_a,
 			xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
 		else if (!prefixcmp(diffopts, "-u"))
 			xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
+		if (o->word_diff) {
+			int i;
+
 			ecbdata.diff_words =
 				xcalloc(1, sizeof(struct diff_words_data));
 			ecbdata.diff_words->file = o->file;
+			ecbdata.diff_words->type = o->word_diff;
 			if (!o->word_regex)
 				o->word_regex = userdiff_word_regex(one);
 			if (!o->word_regex)
@@ -1758,10 +1822,23 @@ static void builtin_diff(const char *name_a,
 					die ("Invalid regular expression: %s",
 							o->word_regex);
 			}
+			for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
+				if (o->word_diff == diff_words_styles[i].type) {
+					ecbdata.diff_words->style =
+						&diff_words_styles[i];
+					break;
+				}
+			}
+			if (DIFF_OPT_TST(o, COLOR_DIFF)) {
+				struct diff_words_style *st = ecbdata.diff_words->style;
+				st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
+				st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
+				st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
+			}
 		}
 		xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
 			      &xpp, &xecfg, &ecb);
-		if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
+		if (o->word_diff)
 			free_diff_words_data(&ecbdata);
 		if (textconv_one)
 			free(mf1.ptr);
@@ -2830,13 +2907,37 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_CLR(options, COLOR_DIFF);
 	else if (!strcmp(arg, "--color-words")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 	}
 	else if (!prefixcmp(arg, "--color-words=")) {
 		DIFF_OPT_SET(options, COLOR_DIFF);
-		DIFF_OPT_SET(options, COLOR_DIFF_WORDS);
+		options->word_diff = DIFF_WORDS_COLOR;
 		options->word_regex = arg + 14;
 	}
+	else if (!strcmp(arg, "--word-diff")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+	}
+	else if (!prefixcmp(arg, "--word-diff=")) {
+		const char *type = arg + 12;
+		if (!strcmp(type, "plain"))
+			options->word_diff = DIFF_WORDS_PLAIN;
+		else if (!strcmp(type, "color")) {
+			DIFF_OPT_SET(options, COLOR_DIFF);
+			options->word_diff = DIFF_WORDS_COLOR;
+		}
+		else if (!strcmp(type, "porcelain"))
+			options->word_diff = DIFF_WORDS_PORCELAIN;
+		else if (!strcmp(type, "none"))
+			options->word_diff = DIFF_WORDS_NONE;
+		else
+			die("bad --word-diff argument: %s", type);
+	}
+	else if (!prefixcmp(arg, "--word-diff-regex=")) {
+		if (options->word_diff == DIFF_WORDS_NONE)
+			options->word_diff = DIFF_WORDS_PLAIN;
+		options->word_regex = arg + 18;
+	}
 	else if (!strcmp(arg, "--exit-code"))
 		DIFF_OPT_SET(options, EXIT_WITH_STATUS);
 	else if (!strcmp(arg, "--quiet"))
diff --git a/diff.h b/diff.h
index 6a71013..9ace08c 100644
--- a/diff.h
+++ b/diff.h
@@ -54,7 +54,7 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_OPT_FIND_COPIES_HARDER  (1 <<  6)
 #define DIFF_OPT_FOLLOW_RENAMES      (1 <<  7)
 #define DIFF_OPT_COLOR_DIFF          (1 <<  8)
-#define DIFF_OPT_COLOR_DIFF_WORDS    (1 <<  9)
+/* (1 <<  9) unused */
 #define DIFF_OPT_HAS_CHANGES         (1 << 10)
 #define DIFF_OPT_QUICK               (1 << 11)
 #define DIFF_OPT_NO_INDEX            (1 << 12)
@@ -79,6 +79,13 @@ typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
 #define DIFF_XDL_SET(opts, flag)    ((opts)->xdl_opts |= XDF_##flag)
 #define DIFF_XDL_CLR(opts, flag)    ((opts)->xdl_opts &= ~XDF_##flag)
 
+enum diff_words_type {
+	DIFF_WORDS_NONE = 0,
+	DIFF_WORDS_PORCELAIN,
+	DIFF_WORDS_PLAIN,
+	DIFF_WORDS_COLOR
+};
+
 struct diff_options {
 	const char *filter;
 	const char *orderfile;
@@ -108,6 +115,7 @@ struct diff_options {
 	int stat_width;
 	int stat_name_width;
 	const char *word_regex;
+	enum diff_words_type word_diff;
 
 	/* this is set by diffcore for DIFF_FORMAT_PATCH */
 	int found_changes;
diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
index 2e2e103..6f7548c 100755
--- a/t/t4034-diff-words.sh
+++ b/t/t4034-diff-words.sh
@@ -55,6 +55,93 @@ test_expect_success 'word diff with runs of whitespace' '
 
 '
 
+test_expect_success '--word-diff=color' '
+
+	word_diff --word-diff=color
+
+'
+
+test_expect_success '--color --word-diff=color' '
+
+	word_diff --color --word-diff=color
+
+'
+
+sed 's/#.*$//' > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+-h(4)
++h(4),hh[44]
+~
+ # significant space
+~
+ a = b + c
+~
+~
++aa = a
+~
+~
++aeff = aeff * ( aaa )
+~
+EOF
+
+test_expect_success '--word-diff=porcelain' '
+
+	word_diff --word-diff=porcelain
+
+'
+
+cat > expect <<EOF
+diff --git a/pre b/post
+index 330b04f..5ed8eff 100644
+--- a/pre
++++ b/post
+@@ -1,3 +1,7 @@
+[-h(4)-]{+h(4),hh[44]+}
+
+a = b + c
+
+{+aa = a+}
+
+{+aeff = aeff * ( aaa )+}
+EOF
+
+test_expect_success '--word-diff=plain' '
+
+	word_diff --word-diff=plain
+
+'
+
+test_expect_success '--word-diff=plain --no-color' '
+
+	word_diff --word-diff=plain --no-color
+
+'
+
+cat > expect <<EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+<RED>[-h(4)-]<RESET><GREEN>{+h(4),hh[44]+}<RESET>
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa )+}<RESET>
+EOF
+
+test_expect_success '--word-diff=plain --color' '
+
+	word_diff --word-diff=plain --color
+
+'
+
 cat > expect <<\EOF
 <WHITE>diff --git a/pre b/post<RESET>
 <WHITE>index 330b04f..5ed8eff 100644<RESET>
@@ -143,6 +230,25 @@ test_expect_success 'command-line overrides config' '
 	word_diff --color-words="[a-z]+"
 '
 
+cat > expect <<\EOF
+<WHITE>diff --git a/pre b/post<RESET>
+<WHITE>index 330b04f..5ed8eff 100644<RESET>
+<WHITE>--- a/pre<RESET>
+<WHITE>+++ b/post<RESET>
+<CYAN>@@ -1,3 +1,7 @@<RESET>
+h(4),<GREEN>{+hh+}<RESET>[44]
+
+a = b + c<RESET>
+
+<GREEN>{+aa = a+}<RESET>
+
+<GREEN>{+aeff = aeff * ( aaa+}<RESET> )
+EOF
+
+test_expect_success 'command-line overrides config: --word-diff-regex' '
+	word_diff --color --word-diff-regex="[a-z]+"
+'
+
 cp expect.non-whitespace-is-word expect
 
 test_expect_success '.gitattributes override config' '
@@ -209,4 +315,20 @@ test_expect_success 'test when words are only removed at the end' '
 
 '
 
+cat > expect <<\EOF
+diff --git a/pre b/post
+index 289cb9d..2d06f37 100644
+--- a/pre
++++ b/post
+@@ -1 +1 @@
+-(:
++(
+EOF
+
+test_expect_success '--word-diff=none' '
+
+	word_diff --word-diff=plain --word-diff=none
+
+'
+
 test_done
-- 
1.7.1.rc1.260.g41ab89

Re: [PATCH v4 1/3] diff: add --word-diff option that generalizes --color-words

[Junio C Hamano]

Looks good; I'll queue this one and hopefully Paul can give feedback to
the gitk patches.

Thanks.

[PATCH v4 2/3] gitk: do not parse " >" context as submodule change

[Thomas Rast]

Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
at the beginning of a line in the submodule code even if we're in the
diff text section and the lines should be treated as context.

Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
case, and move the "  >"/"  <" specific code inside the $diffinhdr
test.  The existing code will set $diffinhdr to 0 when it hits a
"+++", so that it is always 0 when we can hit a context line.
---
 gitk |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/gitk b/gitk
index 1f36a3e..7b8799e 100755
--- a/gitk
+++ b/gitk
@@ -7688,12 +7688,8 @@ proc getblobdiffline {bdf ids} {
 	    lappend ctext_file_lines $fname
 	    makediffhdr $fname $ids
 	    $ctext insert end "\n$line\n" filesep
-	} elseif {![string compare -length 3 "  >" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" dresult
-	} elseif {![string compare -length 3 "  <" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" d0
+	    # pretend we're in a file header to correctly parse "  [><]"
+	    set diffinhdr 1
 	} elseif {$diffinhdr} {
 	    if {![string compare -length 12 "rename from " $line]} {
 		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
@@ -7712,6 +7708,14 @@ proc getblobdiffline {bdf ids} {
 		    set fname [lindex $fname 0]
 		}
 		makediffhdr $fname $ids
+	    } elseif {![string compare -length 3 "  >" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" dresult
+		continue
+	    } elseif {![string compare -length 3 "  <" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" d0
+		continue
 	    } elseif {[string compare -length 3 $line "---"] == 0} {
 		# do nothing
 		continue
-- 
1.7.1.rc1.260.g41ab89

Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change

[Jens Lehmann]

Am 14.04.2010 17:59, schrieb Thomas Rast:
> Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> at the beginning of a line in the submodule code even if we're in the
> diff text section and the lines should be treated as context.
> 
> Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> case, and move the "  >"/"  <" specific code inside the $diffinhdr
> test.  The existing code will set $diffinhdr to 0 when it hits a
> "+++", so that it is always 0 when we can hit a context line.

Thanks for fixing this issue I accidentally introduced!

In that said patch I unfortunately also managed to screw up the
submodule name detection when it was not followed just by commits
(but e.g. by "contains untracked content"). I did already send a
patch to address this issue, but here is a rebased version on top
of your patch series just in case:

--------------------8<--------------------
From: Jens Lehmann <Jens.Lehmann@web.de>
Date: Thu, 15 Apr 2010 21:53:12 +0200
Subject: [PATCH] Teach gitk to display dirty submodules correctly

Since 1.7.1 "git diff --submodule" prints out extra lines when the
submodule contains untracked or modified files. Show all those lines for
one submodule under the same header.

Also e.g. for newly added or removed submodules the submodule name
contained trailing garbage because the extraction of the name was not
done right. Now it scans either for the first hex number followed by a
".." or the string "contains ".

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
---
 gitk-git/gitk |   27 +++++++++++++++++++--------
 1 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index f2a1eb7..93d25ec 100644
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -7530,7 +7530,7 @@ proc getblobdiffs {ids} {
     global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
-    global git_version
+    global git_version currdiffsubmod

     set textconv {}
     if {[package vcompare $git_version "1.6.1"] >= 0} {
@@ -7560,6 +7560,7 @@ proc getblobdiffs {ids} {
     set diffencoding [get_path_encoding {}]
     fconfigure $bdf -blocking 0 -encoding binary -eofchar {}
     set blobdifffd($ids) $bdf
+    set currdiffsubmod ""
     filerun $bdf [list getblobdiffline $bdf $diffids]
 }

@@ -7631,7 +7632,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
-    global worddiff
+    global worddiff currdiffsubmod

     set nr 0
     $ctext conf -state normal
@@ -7712,15 +7713,24 @@ proc getblobdiffline {bdf ids} {

 	} elseif {![string compare -length 10 "Submodule " $line]} {
 	    # start of a new submodule
-	    if {[string compare [$ctext get "end - 4c" end] "\n \n\n"]} {
+	    if {[regexp -indices "\[0-9a-f\]+\\.\\." $line nameend]} {
+		set fname [string range $line 10 [expr [lindex $nameend 0] - 2]]
+	    } else {
+		set fname [string range $line 10 [expr [string first "contains " $line] - 2]]
+	    }
+	    if {$currdiffsubmod != $fname} {
 		$ctext insert end "\n";     # Add newline after commit message
 	    }
 	    set curdiffstart [$ctext index "end - 1c"]
 	    lappend ctext_file_names ""
-	    set fname [string range $line 10 [expr [string last " " $line] - 1]]
-	    lappend ctext_file_lines $fname
-	    makediffhdr $fname $ids
-	    $ctext insert end "\n$line\n" filesep
+	    if {$currdiffsubmod != $fname} {
+		lappend ctext_file_lines $fname
+		makediffhdr $fname $ids
+		set currdiffsubmod $fname
+		$ctext insert end "\n$line\n" filesep
+	    } else {
+		$ctext insert end "$line\n" filesep
+	    }
 	    # pretend we're in a file header to correctly parse "  [><]"
 	    set diffinhdr 1
 	} elseif {$diffinhdr} {
@@ -8588,7 +8598,7 @@ proc do_cmp_commits {a b} {
 }

 proc diffcommits {a b} {
-    global diffcontext diffids blobdifffd diffinhdr
+    global diffcontext diffids blobdifffd diffinhdr currdiffsubmod

     set tmpdir [gitknewtmpdir]
     set fna [file join $tmpdir "commit-[string range $a 0 7]"]
@@ -8609,6 +8619,7 @@ proc diffcommits {a b} {
     set diffids [list commits $a $b]
     set blobdifffd($diffids) $fd
     set diffinhdr 0
+    set currdiffsubmod ""
     filerun $fd [list getblobdiffline $fd $diffids]
 }

-- 
1.7.1.rc1.252.gff9f

Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change

[Paul Mackerras]

On Wed, Apr 14, 2010 at 05:59:07PM +0200, Thomas Rast wrote:

> Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> at the beginning of a line in the submodule code even if we're in the
> diff text section and the lines should be treated as context.
> 
> Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> case, and move the "  >"/"  <" specific code inside the $diffinhdr
> test.  The existing code will set $diffinhdr to 0 when it hits a
> "+++", so that it is always 0 when we can hit a context line.

Looks good, but there's no Signed-off-by?

Paul.

Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change

[Thomas Rast]

Paul Mackerras wrote:
> On Wed, Apr 14, 2010 at 05:59:07PM +0200, Thomas Rast wrote:
> 
> > Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
> > when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
> > at the beginning of a line in the submodule code even if we're in the
> > diff text section and the lines should be treated as context.
> > 
> > Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
> > case, and move the "  >"/"  <" specific code inside the $diffinhdr
> > test.  The existing code will set $diffinhdr to 0 when it hits a
> > "+++", so that it is always 0 when we can hit a context line.
> 
> Looks good, but there's no Signed-off-by?

Whoops, sorry:

Signed-off-by: Thomas Rast <trast@student.ethz.ch>

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

Re: [PATCH v4 2/3] gitk: do not parse " >" context as submodule change

[Paul Mackerras]

On Sat, Apr 17, 2010 at 02:20:55PM +0200, Thomas Rast wrote:

> Whoops, sorry:
> 
> Signed-off-by: Thomas Rast <trast@student.ethz.ch>

Thanks, but now that I have applied Jens Lehmann's patch that also
touches this area, your patch doesn't apply.  Could you rebase it and
send it again?

Thanks,
Paul.

[PATCH v4' 1/2] gitk: do not parse " >" context as submodule change

[Thomas Rast]

Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
at the beginning of a line in the submodule code even if we're in the
diff text section and the lines should be treated as context.

Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
case, and move the "  >"/"  <" specific code inside the $diffinhdr
test.  The existing code will set $diffinhdr to 0 when it hits a
"+++", so that it is always 0 when we can hit a context line.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---

> Thanks, but now that I have applied Jens Lehmann's patch that also
> touches this area, your patch doesn't apply.  Could you rebase it and
> send it again?

Sure.


 gitk |   18 ++++++++++--------
 1 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/gitk b/gitk
index 1b0e09a..6513ef8 100755
--- a/gitk
+++ b/gitk
@@ -7706,14 +7706,8 @@ proc getblobdiffline {bdf ids} {
 	    } else {
 		$ctext insert end "$line\n" filesep
 	    }
-	} elseif {![string compare -length 3 "  >" $line]} {
-	    set $currdiffsubmod ""
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" dresult
-	} elseif {![string compare -length 3 "  <" $line]} {
-	    set $currdiffsubmod ""
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" d0
+	    # pretend we're in a file header to correctly parse "  [><]"
+	    set diffinhdr 1
 	} elseif {$diffinhdr} {
 	    if {![string compare -length 12 "rename from " $line]} {
 		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
@@ -7732,6 +7726,14 @@ proc getblobdiffline {bdf ids} {
 		    set fname [lindex $fname 0]
 		}
 		makediffhdr $fname $ids
+	    } elseif {![string compare -length 3 "  >" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" dresult
+		continue
+	    } elseif {![string compare -length 3 "  <" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" d0
+		continue
 	    } elseif {[string compare -length 3 $line "---"] == 0} {
 		# do nothing
 		continue
-- 
1.7.1.rc1.284.g4b2e3

[PATCH v4' 2/2] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Use the newly added 'diff --word-diff=porcelain' to teach gitk a
color-words mode, with two different modes analogous to the
--word-diff=plain and --word-diff=color settings.  These are selected
by a dropdown box.

As an extra twist, automatically enable this word-diff support when
the user mentions a word-diff related option on the command line.
These options were previously ignored because they would break diff
parsing.

Both of these features are only enabled if we have a version of git
that supports --word-diff=porcelain, tentatively set to 1.7.2.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk |   64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/gitk b/gitk
index 6513ef8..46d1b0e 100755
--- a/gitk
+++ b/gitk
@@ -131,6 +131,7 @@ proc unmerged_files {files} {
 
 proc parseviewargs {n arglist} {
     global vdatemode vmergeonly vflags vdflags vrevs vfiltered vorigargs env
+    global worddiff git_version
 
     set vdatemode($n) 0
     set vmergeonly($n) 0
@@ -168,7 +169,7 @@ proc parseviewargs {n arglist} {
 		lappend diffargs $arg
 	    }
 	    "--raw" - "--patch-with-raw" - "--patch-with-stat" -
-	    "--name-only" - "--name-status" - "--color" - "--color-words" -
+	    "--name-only" - "--name-status" - "--color" -
 	    "--log-size" - "--pretty=*" - "--decorate" - "--abbrev-commit" -
 	    "--cc" - "-z" - "--header" - "--parents" - "--boundary" -
 	    "--no-color" - "-g" - "--walk-reflogs" - "--no-walk" -
@@ -177,6 +178,18 @@ proc parseviewargs {n arglist} {
 		# These cause our parsing of git log's output to fail, or else
 		# they're options we want to set ourselves, so ignore them.
 	    }
+	    "--color-words*" - "--word-diff=color" {
+		# These trigger a word diff in the console interface,
+		# so help the user by enabling our own support
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Color words"]
+		}
+	    }
+	    "--word-diff*" {
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Markup words"]
+		}
+	    }
 	    "--stat=*" - "--numstat" - "--shortstat" - "--summary" -
 	    "--check" - "--exit-code" - "--quiet" - "--topo-order" -
 	    "--full-history" - "--dense" - "--sparse" -
@@ -1970,6 +1983,8 @@ proc makewindow {} {
     global fprogitem fprogcoord lastprogupdate progupdatepending
     global rprogitem rprogcoord rownumsel numcommits
     global have_tk85 use_ttk NS
+    global git_version
+    global worddiff
 
     # The "mc" arguments here are purely so that xgettext
     # sees the following string as needing to be translated
@@ -2243,6 +2258,15 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+
+    set worddiff [mc "Line diff"]
+    if {[package vcompare $git_version "1.7.2"] >= 0} {
+	makedroplist .bleft.mid.worddiff worddiff [mc "Line diff"] \
+	    [mc "Markup words"] [mc "Color words"]
+	trace add variable worddiff write changeworddiff
+	pack .bleft.mid.worddiff -side left -padx 5
+    }
+
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7502,11 +7526,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {name ix op} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version currdiffsubmod
@@ -7523,6 +7552,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff ne [mc "Line diff"]} {
+	append cmd " --word-diff=porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7608,6 +7640,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline currdiffsubmod
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7749,15 +7782,28 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    set dowords [expr {$worddiff ne [mc "Line diff"] && $diffnparents == 1}]
+	    set words_pre_markup ""
+	    set words_post_markup ""
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$dowords} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "\[-$line-\]" $tag$num
+		    } else {
+			$ctext insert end "$line" $tag$num
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7772,6 +7818,8 @@ proc getblobdiffline {bdf ids} {
 				lappend tags m$num
 			    }
 			}
+			set words_pre_markup "{+"
+			set words_post_markup "+}"
 		    }
 		    if {$targetline ne {}} {
 			if {$diffline == $targetline} {
@@ -7781,8 +7829,17 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "$words_pre_markup$line$words_post_markup" $tags
+		    } else {
+			$ctext insert end "$line" $tags
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$dowords && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11393,6 +11450,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff ""
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.1.rc1.284.g4b2e3

Re: [PATCH v4' 1/2] gitk: do not parse " >" context as submodule change

[Jens Lehmann]

Am 19.04.2010 18:27, schrieb Thomas Rast:
>> Thanks, but now that I have applied Jens Lehmann's patch that also
>> touches this area, your patch doesn't apply.  Could you rebase it and
>> send it again?
> 
> Sure.

There might be a problem with this rebase. Unfortunately I am very
short on time, so I can't test this today.

I think setting the $currdiffsubmod variable to the empty string
has to show up in the two sections formatting the lines with
"  >" & "  <".


>  gitk |   18 ++++++++++--------
>  1 files changed, 10 insertions(+), 8 deletions(-)
> 
> diff --git a/gitk b/gitk
> index 1b0e09a..6513ef8 100755
> --- a/gitk
> +++ b/gitk
> @@ -7706,14 +7706,8 @@ proc getblobdiffline {bdf ids} {
>  	    } else {
>  		$ctext insert end "$line\n" filesep
>  	    }
> -	} elseif {![string compare -length 3 "  >" $line]} {
> -	    set $currdiffsubmod ""
> -	    set line [encoding convertfrom $diffencoding $line]
> -	    $ctext insert end "$line\n" dresult
> -	} elseif {![string compare -length 3 "  <" $line]} {
> -	    set $currdiffsubmod ""
> -	    set line [encoding convertfrom $diffencoding $line]
> -	    $ctext insert end "$line\n" d0
> +	    # pretend we're in a file header to correctly parse "  [><]"
> +	    set diffinhdr 1
>  	} elseif {$diffinhdr} {
>  	    if {![string compare -length 12 "rename from " $line]} {
>  		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
> @@ -7732,6 +7726,14 @@ proc getblobdiffline {bdf ids} {
>  		    set fname [lindex $fname 0]
>  		}
>  		makediffhdr $fname $ids
> +	    } elseif {![string compare -length 3 "  >" $line]} {

I suspect we need a 'set $currdiffsubmod ""' here

> +		set line [encoding convertfrom $diffencoding $line]
> +		$ctext insert end "$line\n" dresult
> +		continue
> +	    } elseif {![string compare -length 3 "  <" $line]} {

and here.

> +		set line [encoding convertfrom $diffencoding $line]
> +		$ctext insert end "$line\n" d0
> +		continue
>  	    } elseif {[string compare -length 3 $line "---"] == 0} {
>  		# do nothing
>  		continue

If you can wait until tomorrow I can check that.

Re: [PATCH v4' 1/2] gitk: do not parse " >" context as submodule change

[Jens Lehmann]

Am 19.04.2010 19:22, schrieb Jens Lehmann:
> Am 19.04.2010 18:27, schrieb Thomas Rast:
>>> Thanks, but now that I have applied Jens Lehmann's patch that also
>>> touches this area, your patch doesn't apply.  Could you rebase it and
>>> send it again?
>>
>> Sure.
> 
> There might be a problem with this rebase. Unfortunately I am very
> short on time, so I can't test this today.

I successfully tested this patch, this was a false alarm from my side.
Sorry for the noise.

Tested-by: Jens.Lehmann@web.de

[PATCH v4 3/3] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Use the newly added 'diff --word-diff=porcelain' to teach gitk a
color-words mode, with two different modes analogous to the
--word-diff=plain and --word-diff=color settings.  These are selected
by a dropdown box.

As an extra twist, automatically enable this word-diff support when
the user mentions a word-diff related option on the command line.
These options were previously ignored because they would break diff
parsing.

Both of these features are only enabled if we have a version of git
that supports --word-diff=porcelain, tentatively set to 1.7.2.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk |   64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/gitk b/gitk
index 7b8799e..f2a1eb7 100755
--- a/gitk
+++ b/gitk
@@ -131,6 +131,7 @@ proc unmerged_files {files} {
 
 proc parseviewargs {n arglist} {
     global vdatemode vmergeonly vflags vdflags vrevs vfiltered vorigargs env
+    global worddiff git_version
 
     set vdatemode($n) 0
     set vmergeonly($n) 0
@@ -168,7 +169,7 @@ proc parseviewargs {n arglist} {
 		lappend diffargs $arg
 	    }
 	    "--raw" - "--patch-with-raw" - "--patch-with-stat" -
-	    "--name-only" - "--name-status" - "--color" - "--color-words" -
+	    "--name-only" - "--name-status" - "--color" -
 	    "--log-size" - "--pretty=*" - "--decorate" - "--abbrev-commit" -
 	    "--cc" - "-z" - "--header" - "--parents" - "--boundary" -
 	    "--no-color" - "-g" - "--walk-reflogs" - "--no-walk" -
@@ -177,6 +178,18 @@ proc parseviewargs {n arglist} {
 		# These cause our parsing of git log's output to fail, or else
 		# they're options we want to set ourselves, so ignore them.
 	    }
+	    "--color-words*" - "--word-diff=color" {
+		# These trigger a word diff in the console interface,
+		# so help the user by enabling our own support
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Color words"]
+		}
+	    }
+	    "--word-diff*" {
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Markup words"]
+		}
+	    }
 	    "--stat=*" - "--numstat" - "--shortstat" - "--summary" -
 	    "--check" - "--exit-code" - "--quiet" - "--topo-order" -
 	    "--full-history" - "--dense" - "--sparse" -
@@ -1967,6 +1980,8 @@ proc makewindow {} {
     global fprogitem fprogcoord lastprogupdate progupdatepending
     global rprogitem rprogcoord rownumsel numcommits
     global have_tk85 use_ttk NS
+    global git_version
+    global worddiff
 
     # The "mc" arguments here are purely so that xgettext
     # sees the following string as needing to be translated
@@ -2240,6 +2255,15 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+
+    set worddiff [mc "Line diff"]
+    if {[package vcompare $git_version "1.7.2"] >= 0} {
+	makedroplist .bleft.mid.worddiff worddiff [mc "Line diff"] \
+	    [mc "Markup words"] [mc "Color words"]
+	trace add variable worddiff write changeworddiff
+	pack .bleft.mid.worddiff -side left -padx 5
+    }
+
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7494,11 +7518,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {name ix op} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version
@@ -7515,6 +7544,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff ne [mc "Line diff"]} {
+	append cmd " --word-diff=porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7599,6 +7631,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7731,15 +7764,28 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    set dowords [expr {$worddiff ne [mc "Line diff"] && $diffnparents == 1}]
+	    set words_pre_markup ""
+	    set words_post_markup ""
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$dowords} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "\[-$line-\]" $tag$num
+		    } else {
+			$ctext insert end "$line" $tag$num
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7754,6 +7800,8 @@ proc getblobdiffline {bdf ids} {
 				lappend tags m$num
 			    }
 			}
+			set words_pre_markup "{+"
+			set words_post_markup "+}"
 		    }
 		    if {$targetline ne {}} {
 			if {$diffline == $targetline} {
@@ -7763,8 +7811,17 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "$words_pre_markup$line$words_post_markup" $tags
+		    } else {
+			$ctext insert end "$line" $tags
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$dowords && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11383,6 +11440,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff ""
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.1.rc1.260.g41ab89

Re: [PATCH v4 3/3] gitk: add the equivalent of diff --color-words

[Paul Mackerras]

On Wed, Apr 14, 2010 at 05:59:08PM +0200, Thomas Rast wrote:

> Use the newly added 'diff --word-diff=porcelain' to teach gitk a
> color-words mode, with two different modes analogous to the
> --word-diff=plain and --word-diff=color settings.  These are selected
> by a dropdown box.
> 
> As an extra twist, automatically enable this word-diff support when
> the user mentions a word-diff related option on the command line.
> These options were previously ignored because they would break diff
> parsing.
> 
> Both of these features are only enabled if we have a version of git
> that supports --word-diff=porcelain, tentatively set to 1.7.2.
> 
> Signed-off-by: Thomas Rast <trast@student.ethz.ch>

Looks fine.  The only nit I can see is that a "--word-diffoobar"
option would get treated as "--word-diff=plain" rather than giving an
error or being passed as-is to git log.

When does this need to go in, i.e. when is the git patch likely to go
in?

Paul.

Re: [PATCH v4 3/3] gitk: add the equivalent of diff --color-words

[Junio C Hamano]

Paul Mackerras <paulus@samba.org> writes:

> When does this need to go in, i.e. when is the git patch likely to go
> in?

I am expecting that this will be in soon after the current 1.7.1 cycle,
sometime around early-to-mid May timeframe.

[PATCH v3 2/3] gitk: do not parse " >" context as submodule change

[Thomas Rast]

Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
at the beginning of a line in the submodule code even if we're in the
diff text section and the lines should be treated as context.

Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
case, and move the "  >"/"  <" specific code inside the $diffinhdr
test.  The existing code will set $diffinhdr to 0 when it hits a
"+++", so that it is always 0 when we can hit a context line.
---
 gitk |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/gitk b/gitk
index 1f36a3e..e9e284e 100755
--- a/gitk
+++ b/gitk
@@ -7688,12 +7688,8 @@ proc getblobdiffline {bdf ids} {
 	    lappend ctext_file_lines $fname
 	    makediffhdr $fname $ids
 	    $ctext insert end "\n$line\n" filesep
-	} elseif {![string compare -length 3 "  >" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" dresult
-	} elseif {![string compare -length 3 "  <" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" d0
+	    # pretend we're in a file header to correctly parse "  [><]"
+	    set diffinhdr 1
 	} elseif {$diffinhdr} {
 	    if {![string compare -length 12 "rename from " $line]} {
 		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
@@ -7712,6 +7708,12 @@ proc getblobdiffline {bdf ids} {
 		    set fname [lindex $fname 0]
 		}
 		makediffhdr $fname $ids
+	    } elseif {![string compare -length 3 "  >" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" dresult
+	    } elseif {![string compare -length 3 "  <" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" d0
 	    } elseif {[string compare -length 3 $line "---"] == 0} {
 		# do nothing
 		continue
-- 
1.7.1.rc0.262.gff1a3

[PATCH v3.1] gitk: do not parse " >" context as submodule change

[Thomas Rast]

Since 5c838d2 (gitk: Use the --submodule option for displaying diffs
when available, 2009-10-28) gitk erroneously matches "  >" and "  <"
at the beginning of a line in the submodule code even if we're in the
diff text section and the lines should be treated as context.

Fix by (ab)using the $diffinhdr variable also in the 'Submodule...'
case, and move the "  >"/"  <" specific code inside the $diffinhdr
test.  The existing code will set $diffinhdr to 0 when it hits a
"+++", so that it is always 0 when we can hit a context line.
---

I just noticed that I forgot to add the 'continue' that prevents the
final 'insert' in the $diffinhdr block from kicking in, which resulted
in doubling of the lines.  This one has them.  Sorry for the noise.


 gitk |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/gitk b/gitk
index 1f36a3e..7b8799e 100755
--- a/gitk
+++ b/gitk
@@ -7688,12 +7688,8 @@ proc getblobdiffline {bdf ids} {
 	    lappend ctext_file_lines $fname
 	    makediffhdr $fname $ids
 	    $ctext insert end "\n$line\n" filesep
-	} elseif {![string compare -length 3 "  >" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" dresult
-	} elseif {![string compare -length 3 "  <" $line]} {
-	    set line [encoding convertfrom $diffencoding $line]
-	    $ctext insert end "$line\n" d0
+	    # pretend we're in a file header to correctly parse "  [><]"
+	    set diffinhdr 1
 	} elseif {$diffinhdr} {
 	    if {![string compare -length 12 "rename from " $line]} {
 		set fname [string range $line [expr 6 + [string first " from " $line] ] end]
@@ -7712,6 +7708,14 @@ proc getblobdiffline {bdf ids} {
 		    set fname [lindex $fname 0]
 		}
 		makediffhdr $fname $ids
+	    } elseif {![string compare -length 3 "  >" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" dresult
+		continue
+	    } elseif {![string compare -length 3 "  <" $line]} {
+		set line [encoding convertfrom $diffencoding $line]
+		$ctext insert end "$line\n" d0
+		continue
 	    } elseif {[string compare -length 3 $line "---"] == 0} {
 		# do nothing
 		continue
-- 
1.7.1.rc0.260.g2b919

[PATCH v3 3/3] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Use the newly added 'diff --word-diff=porcelain' to teach gitk a
color-words mode, with two different modes analogous to the
--word-diff=plain and --word-diff=color settings.  These are selected
by a dropdown box.

As an extra twist, automatically enable this word-diff support when
the user mentions a word-diff related option on the command line.
These options were previously ignored because they would break diff
parsing.

Both of these features are only enabled if we have a version of git
that supports --word-diff=porcelain, tentatively set to 1.7.2.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk |   64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/gitk b/gitk
index e9e284e..466c328 100755
--- a/gitk
+++ b/gitk
@@ -131,6 +131,7 @@ proc unmerged_files {files} {
 
 proc parseviewargs {n arglist} {
     global vdatemode vmergeonly vflags vdflags vrevs vfiltered vorigargs env
+    global worddiff git_version
 
     set vdatemode($n) 0
     set vmergeonly($n) 0
@@ -168,7 +169,7 @@ proc parseviewargs {n arglist} {
 		lappend diffargs $arg
 	    }
 	    "--raw" - "--patch-with-raw" - "--patch-with-stat" -
-	    "--name-only" - "--name-status" - "--color" - "--color-words" -
+	    "--name-only" - "--name-status" - "--color" -
 	    "--log-size" - "--pretty=*" - "--decorate" - "--abbrev-commit" -
 	    "--cc" - "-z" - "--header" - "--parents" - "--boundary" -
 	    "--no-color" - "-g" - "--walk-reflogs" - "--no-walk" -
@@ -177,6 +178,18 @@ proc parseviewargs {n arglist} {
 		# These cause our parsing of git log's output to fail, or else
 		# they're options we want to set ourselves, so ignore them.
 	    }
+	    "--color-words*" - "--word-diff=color" {
+		# These trigger a word diff in the console interface,
+		# so help the user by enabling our own support
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Color words"]
+		}
+	    }
+	    "--word-diff*" {
+		if {[package vcompare $git_version "1.7.2"] >= 0} {
+		    set worddiff [mc "Markup words"]
+		}
+	    }
 	    "--stat=*" - "--numstat" - "--shortstat" - "--summary" -
 	    "--check" - "--exit-code" - "--quiet" - "--topo-order" -
 	    "--full-history" - "--dense" - "--sparse" -
@@ -1967,6 +1980,8 @@ proc makewindow {} {
     global fprogitem fprogcoord lastprogupdate progupdatepending
     global rprogitem rprogcoord rownumsel numcommits
     global have_tk85 use_ttk NS
+    global git_version
+    global worddiff
 
     # The "mc" arguments here are purely so that xgettext
     # sees the following string as needing to be translated
@@ -2240,6 +2255,15 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+
+    set worddiff [mc "Line diff"]
+    if {[package vcompare $git_version "1.7.2"] >= 0} {
+	makedroplist .bleft.mid.worddiff worddiff [mc "Line diff"] \
+	    [mc "Markup words"] [mc "Color words"]
+	trace add variable worddiff write changeworddiff
+	pack .bleft.mid.worddiff -side left -padx 5
+    }
+
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7494,11 +7518,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {name ix op} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version
@@ -7515,6 +7544,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff ne [mc "Line diff"]} {
+	append cmd " --word-diff=porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7599,6 +7631,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7729,15 +7762,28 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    set dowords [expr {$worddiff ne [mc "Line diff"] && $diffnparents == 1}]
+	    set words_pre_markup ""
+	    set words_post_markup ""
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$dowords} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "\[-$line-\]" $tag$num
+		    } else {
+			$ctext insert end "$line" $tag$num
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7752,6 +7798,8 @@ proc getblobdiffline {bdf ids} {
 				lappend tags m$num
 			    }
 			}
+			set words_pre_markup "{+"
+			set words_post_markup "+}"
 		    }
 		    if {$targetline ne {}} {
 			if {$diffline == $targetline} {
@@ -7761,8 +7809,17 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    if {$dowords && $worddiff eq [mc "Markup words"]} {
+			$ctext insert end "$words_pre_markup$line$words_post_markup" $tags
+		    } else {
+			$ctext insert end "$line" $tags
+		    }
+		    if {!$dowords} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$dowords && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11381,6 +11438,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff ""
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.1.rc0.262.gff1a3

Re: [PATCH 1/2] diff: add --word-diff option that generalizes --color-words

[Thomas Rast]

Junio C Hamano wrote:
> 
> There is one difference between other uses of colors and color-words, but
> I can imagine that ordinary people may not have even realized nor thought
> about it.
> 
> To people who are somewhat but not completely color-challenged (like
> myself), it still helps to paint hunk headers in a color that is different
> from the body text to make the boundary of each hunk more visible.  Even
> without the perception of exact color/hue, the contrast alone helps in
> that case.

I see now.  My apologies for not thinking of that case!

I'll make a new patch.

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

[PATCH 2/2] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Use the newly added 'diff --word-diff=porcelain' to teach gitk a
color-words mode, triggered by a checkbox.

As an extra twist, automatically enable this word-diff support when
the user mentions a word-diff related option on the command line.
These options were previously ignored because they would break diff
parsing.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk |   37 ++++++++++++++++++++++++++++++++++---
 1 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/gitk b/gitk
index 1f36a3e..05ed053 100755
--- a/gitk
+++ b/gitk
@@ -131,6 +131,7 @@ proc unmerged_files {files} {
 
 proc parseviewargs {n arglist} {
     global vdatemode vmergeonly vflags vdflags vrevs vfiltered vorigargs env
+    global worddiff
 
     set vdatemode($n) 0
     set vmergeonly($n) 0
@@ -168,7 +169,7 @@ proc parseviewargs {n arglist} {
 		lappend diffargs $arg
 	    }
 	    "--raw" - "--patch-with-raw" - "--patch-with-stat" -
-	    "--name-only" - "--name-status" - "--color" - "--color-words" -
+	    "--name-only" - "--name-status" - "--color" -
 	    "--log-size" - "--pretty=*" - "--decorate" - "--abbrev-commit" -
 	    "--cc" - "-z" - "--header" - "--parents" - "--boundary" -
 	    "--no-color" - "-g" - "--walk-reflogs" - "--no-walk" -
@@ -177,6 +178,11 @@ proc parseviewargs {n arglist} {
 		# These cause our parsing of git log's output to fail, or else
 		# they're options we want to set ourselves, so ignore them.
 	    }
+	    "--color-words*" - "--word-diff*" {
+		# These trigger a word diff in the console interface,
+		# so help the user by enabling our own support
+		set worddiff 1
+	    }
 	    "--stat=*" - "--numstat" - "--shortstat" - "--summary" -
 	    "--check" - "--exit-code" - "--quiet" - "--topo-order" -
 	    "--full-history" - "--dense" - "--sparse" -
@@ -2240,6 +2246,9 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+    ${NS}::checkbutton .bleft.mid.worddiff -text [mc "Word diff"] \
+	-command changeworddiff -variable worddiff
+    pack .bleft.mid.worddiff -side left -padx 5
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7494,11 +7503,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version
@@ -7515,6 +7529,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff} {
+	append cmd " --word-diff=porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7599,6 +7616,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7727,15 +7745,22 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    set dowords [expr {$worddiff && $diffnparents == 1}]
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$dowords} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    $ctext insert end "$line" $tag$num
+		    if {!$dowords} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7759,8 +7784,13 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    $ctext insert end "$line" $tags
+		    if {!$dowords} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$dowords && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11379,6 +11409,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff 0
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.0.3.521.ga1e9e

[RFC PATCH 0/2] gitk --color-words

[Thomas Rast]

This little pair of patches teaches gitk a color-words diff view.

To get there, I finally got rid of the assumption that --color-words
only ever needs to output ANSI(?) color sequences.  Hopefully this
will help other people to use --color-words in nice frontends.

It uses an ad-hoc output format where newlines in the output are
insignificant (so as to be able to speak about added/removed words)
and newlines from the input are output as a line with only a '~'.

RFC among other things because

* I chose ~ more or less randomly.  Do any diff implementations out
  there use it for some other purpose?

* The --color-words code was the only user of color_fwrite_lines() so
  I tweaked it according to my needs.  But that makes it highly
  diff-specific again, so it's not in color.c any more.  Did anyone
  else intend to use it?

* The Tk part of the patch is 95% voodoo of the
  cut&paste-from-elsewhere vintage and I have no clue whether it works
  only by accident

* I still need to do some things: add docs for --porcelain, add tests
  to the first patch, move the gitk patch to affect only the subtree

* I'm not even burning midnight oil any more

Thomas Rast (2):
  Add diff --porcelain option for --color-words
  gitk: add the equivalent of diff --color-words

 color.c       |   28 ---------------
 color.h       |    1 -
 diff.c        |  105 +++++++++++++++++++++++++++++++++++++++++++++++---------
 diff.h        |    1 +
 gitk-git/gitk |   29 +++++++++++++++-
 5 files changed, 116 insertions(+), 48 deletions(-)

[PATCH 2/2] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Use the newly added 'diff --color-words --porcelain' to teach gitk a
color-words mode, triggered by a checkbox.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
---
 gitk-git/gitk |   29 +++++++++++++++++++++++++++--
 1 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/gitk-git/gitk b/gitk-git/gitk
index 1f36a3e..ee6e39c 100644
--- a/gitk-git/gitk
+++ b/gitk-git/gitk
@@ -2240,6 +2240,9 @@ proc makewindow {} {
     ${NS}::checkbutton .bleft.mid.ignspace -text [mc "Ignore space change"] \
 	-command changeignorespace -variable ignorespace
     pack .bleft.mid.ignspace -side left -padx 5
+    ${NS}::checkbutton .bleft.mid.worddiff -text [mc "Word diff"] \
+	-command changeworddiff -variable worddiff
+    pack .bleft.mid.worddiff -side left -padx 5
     set ctext .bleft.bottom.ctext
     text $ctext -background $bgcolor -foreground $fgcolor \
 	-state disabled -font textfont \
@@ -7494,11 +7497,16 @@ proc changeignorespace {} {
     reselectline
 }
 
+proc changeworddiff {} {
+    reselectline
+}
+
 proc getblobdiffs {ids} {
     global blobdifffd diffids env
     global diffinhdr treediffs
     global diffcontext
     global ignorespace
+    global worddiff
     global limitdiffs vfilelimit curview
     global diffencoding targetline diffnparents
     global git_version
@@ -7515,6 +7523,9 @@ proc getblobdiffs {ids} {
     if {$ignorespace} {
 	append cmd " -w"
     }
+    if {$worddiff} {
+	append cmd " --color-words --porcelain"
+    }
     if {$limitdiffs && $vfilelimit($curview) ne {}} {
 	set cmd [concat $cmd -- $vfilelimit($curview)]
     }
@@ -7599,6 +7610,7 @@ proc getblobdiffline {bdf ids} {
     global ctext_file_names ctext_file_lines
     global diffinhdr treediffs mergemax diffnparents
     global diffencoding jump_to_here targetline diffline
+    global worddiff
 
     set nr 0
     $ctext conf -state normal
@@ -7727,15 +7739,22 @@ proc getblobdiffline {bdf ids} {
 	    # parse the prefix - one ' ', '-' or '+' for each parent
 	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
 	    set tag [expr {$diffnparents > 1? "m": "d"}]
+	    puts "prefix is '$prefix'"
 	    if {[string trim $prefix " -+"] eq {}} {
 		# prefix only has " ", "-" and "+" in it: normal diff line
 		set num [string first "-" $prefix]
+		if {$worddiff} {
+		    set line [string range $line 1 end]
+		}
 		if {$num >= 0} {
 		    # removed line, first parent with line is $num
 		    if {$num >= $mergemax} {
 			set num "max"
 		    }
-		    $ctext insert end "$line\n" $tag$num
+		    $ctext insert end "$line" $tag$num
+		    if {!$worddiff} {
+			$ctext insert end "\n" $tag$num
+		    }
 		} else {
 		    set tags {}
 		    if {[string first "+" $prefix] >= 0} {
@@ -7759,8 +7778,13 @@ proc getblobdiffline {bdf ids} {
 			    incr diffline
 			}
 		    }
-		    $ctext insert end "$line\n" $tags
+		    $ctext insert end "$line" $tags
+		    if {!$worddiff} {
+			$ctext insert end "\n" $tags
+		    }
 		}
+	    } elseif {$worddiff && $prefix eq "~"} {
+		$ctext insert end "\n" {}
 	    } else {
 		# "\ No newline at end of file",
 		# or something else we don't recognize
@@ -11379,6 +11403,7 @@ if {[tk windowingsystem] eq "win32"} {
 set diffcolors {red "#00a000" blue}
 set diffcontext 3
 set ignorespace 0
+set worddiff 0
 set markbgcolor "#e0e0ff"
 
 set circlecolors {white blue gray blue blue}
-- 
1.7.0.3.522.ga3f6f.dirty

Re: [PATCH 2/2] gitk: add the equivalent of diff --color-words

[Thomas Rast]

Thomas Rast wrote:
> @@ -7727,15 +7739,22 @@ proc getblobdiffline {bdf ids} {
>  	    # parse the prefix - one ' ', '-' or '+' for each parent
>  	    set prefix [string range $line 0 [expr {$diffnparents - 1}]]
>  	    set tag [expr {$diffnparents > 1? "m": "d"}]
> +	    puts "prefix is '$prefix'"

This is a leftover debugging print and should be removed if you want
to try it... sorry for the noise.

-- 
Thomas Rast
trast@{inf,student}.ethz.ch