[PATCH 0/3] Resending sb/config-write-fix

[PATCH 0/3] Resending sb/config-write-fix

[Stefan Beller]

This is a resend of sb/config-write-fix, with a slightly
better commit message and a renamed variable.

Thanks,
Stefan


Stefan Beller (3):
  t1300: document current behavior of setting options
  config: fix case sensitive subsection names on writing
  git-config: document accidental multi-line setting in deprecated
    syntax

 Documentation/git-config.txt | 21 +++++++++
 config.c                     | 12 ++++-
 t/t1300-config.sh            | 87 ++++++++++++++++++++++++++++++++++++
 3 files changed, 119 insertions(+), 1 deletion(-)

./git-range-diff origin/sb/config-write-fix...HEAD >>0000-cover-letter.patch 
2.18.0.597.ga71716f1ad-goog

1:  999d9026272 ! 1:  e40f57f3da1 t1300: document current behavior of setting options
    @@ -7,7 +7,6 @@
         for the follow up that will fix some issues with the current behavior.
     
         Signed-off-by: Stefan Beller <sbeller@google.com>
    -    Signed-off-by: Junio C Hamano <gitster@pobox.com>
     
      diff --git a/t/t1300-config.sh b/t/t1300-config.sh
      --- a/t/t1300-config.sh
2:  c667e555066 ! 2:  f01cb1d9dae config: fix case sensitive subsection names on writing
    @@ -2,8 +2,8 @@
     
         config: fix case sensitive subsection names on writing
     
    -    A use reported a submodule issue regarding strange case indentation
    -    issues, but it could be boiled down to the following test case:
    +    A user reported a submodule issue regarding a section mix-up,
    +    but it could be boiled down to the following test case:
     
           $ git init test  && cd test
           $ git config foo."Bar".key test
    @@ -32,7 +32,6 @@
     
         Reported-by: JP Sugarbroad <jpsugar@google.com>
         Signed-off-by: Stefan Beller <sbeller@google.com>
    -    Signed-off-by: Junio C Hamano <gitster@pobox.com>
     
      diff --git a/config.c b/config.c
      --- a/config.c
    @@ -41,7 +40,7 @@
      	int eof;
      	struct strbuf value;
      	struct strbuf var;
    -+	unsigned section_name_old_dot_style : 1;
    ++	unsigned subsection_case_sensitive : 1;
      
      	int (*do_fgetc)(struct config_source *c);
      	int (*do_ungetc)(int c, struct config_source *conf);
    @@ -49,7 +48,7 @@
      
      static int get_extended_base_var(struct strbuf *name, int c)
      {
    -+	cf->section_name_old_dot_style = 0;
    ++	cf->subsection_case_sensitive = 0;
      	do {
      		if (c == '\n')
      			goto error_incomplete_line;
    @@ -57,7 +56,7 @@
      
      static int get_base_var(struct strbuf *name)
      {
    -+	cf->section_name_old_dot_style = 1;
    ++	cf->subsection_case_sensitive = 1;
      	for (;;) {
      		int c = get_next_char();
      		if (cf->eof)
    @@ -70,7 +69,7 @@
      		if (cf->var.len < 2 || cf->var.buf[cf->var.len - 1] != '.')
      			return error("invalid section name '%s'", cf->var.buf);
      
    -+		if (cf->section_name_old_dot_style)
    ++		if (cf->subsection_case_sensitive)
     +			cmpfn = strncasecmp;
     +		else
     +			cmpfn = strncmp;
3:  6749bb283a8 ! 3:  6b5ad773490 git-config: document accidental multi-line setting in deprecated syntax
    @@ -29,7 +29,6 @@
         spend time on fixing the behavior and just document it instead.
     
         Signed-off-by: Stefan Beller <sbeller@google.com>
    -    Signed-off-by: Junio C Hamano <gitster@pobox.com>
     
      diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
      --- a/Documentation/git-config.txt

[PATCH 1/3] t1300: document current behavior of setting options

[Stefan Beller]

This documents current behavior of the config machinery, when changing
the value of some settings. This patch just serves to provide a baseline
for the follow up that will fix some issues with the current behavior.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 t/t1300-config.sh | 86 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

diff --git a/t/t1300-config.sh b/t/t1300-config.sh
index e43982a9c1f..c15c19bf78d 100755
--- a/t/t1300-config.sh
+++ b/t/t1300-config.sh
@@ -1188,6 +1188,92 @@ test_expect_success 'last one wins: three level vars' '
 	test_cmp expect actual
 '
 
+test_expect_success 'old-fashioned settings are case insensitive' '
+	test_when_finished "rm -f testConfig testConfig_expect testConfig_actual" &&
+
+	cat >testConfig_actual <<-EOF &&
+		[V.A]
+		r = value1
+	EOF
+	q_to_tab >testConfig_expect <<-EOF &&
+		[V.A]
+		Qr = value2
+	EOF
+	git config -f testConfig_actual "v.a.r" value2 &&
+	test_cmp testConfig_expect testConfig_actual &&
+
+	cat >testConfig_actual <<-EOF &&
+		[V.A]
+		r = value1
+	EOF
+	q_to_tab >testConfig_expect <<-EOF &&
+		[V.A]
+		QR = value2
+	EOF
+	git config -f testConfig_actual "V.a.R" value2 &&
+	test_cmp testConfig_expect testConfig_actual &&
+
+	cat >testConfig_actual <<-EOF &&
+		[V.A]
+		r = value1
+	EOF
+	q_to_tab >testConfig_expect <<-EOF &&
+		[V.A]
+		r = value1
+		Qr = value2
+	EOF
+	git config -f testConfig_actual "V.A.r" value2 &&
+	test_cmp testConfig_expect testConfig_actual &&
+
+	cat >testConfig_actual <<-EOF &&
+		[V.A]
+		r = value1
+	EOF
+	q_to_tab >testConfig_expect <<-EOF &&
+		[V.A]
+		r = value1
+		Qr = value2
+	EOF
+	git config -f testConfig_actual "v.A.r" value2 &&
+	test_cmp testConfig_expect testConfig_actual
+'
+
+test_expect_success 'setting different case sensitive subsections ' '
+	test_when_finished "rm -f testConfig testConfig_expect testConfig_actual" &&
+
+	cat >testConfig_actual <<-EOF &&
+		[V "A"]
+		R = v1
+		[K "E"]
+		Y = v1
+		[a "b"]
+		c = v1
+		[d "e"]
+		f = v1
+	EOF
+	q_to_tab >testConfig_expect <<-EOF &&
+		[V "A"]
+		Qr = v2
+		[K "E"]
+		Qy = v2
+		[a "b"]
+		Qc = v2
+		[d "e"]
+		f = v1
+		Qf = v2
+	EOF
+	# exact match
+	git config -f testConfig_actual a.b.c v2 &&
+	# match section and subsection, key is cased differently.
+	git config -f testConfig_actual K.E.y v2 &&
+	# section and key are matched case insensitive, but subsection needs
+	# to match; When writing out new values only the key is adjusted
+	git config -f testConfig_actual v.A.r v2 &&
+	# subsection is not matched:
+	git config -f testConfig_actual d.E.f v2 &&
+	test_cmp testConfig_expect testConfig_actual
+'
+
 for VAR in a .a a. a.0b a."b c". a."b c".0d
 do
 	test_expect_success "git -c $VAR=VAL rejects invalid '$VAR'" '
-- 
2.18.0.597.ga71716f1ad-goog

[PATCH 2/3] config: fix case sensitive subsection names on writing

[Stefan Beller]

A user reported a submodule issue regarding a section mix-up,
but it could be boiled down to the following test case:

  $ git init test  && cd test
  $ git config foo."Bar".key test
  $ git config foo."bar".key test
  $ tail -n 3 .git/config
  [foo "Bar"]
        key = test
        key = test

Sub sections are case sensitive and we have a test for correctly reading
them. However we do not have a test for writing out config correctly with
case sensitive subsection names, which is why this went unnoticed in
6ae996f2acf (git_config_set: make use of the config parser's event
stream, 2018-04-09)

Unfortunately we have to make a distinction between old style configuration
that looks like

  [foo.Bar]
        key = test

and the new quoted style as seen above. The old style is documented as
case-agnostic, hence we need to keep 'strncasecmp'; although the
resulting setting for the old style config differs from the configuration.
That will be fixed in a follow up patch.

Reported-by: JP Sugarbroad <jpsugar@google.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
---
 config.c          | 12 +++++++++++-
 t/t1300-config.sh |  1 +
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/config.c b/config.c
index 02050529788..27e800c7ce8 100644
--- a/config.c
+++ b/config.c
@@ -35,6 +35,7 @@ struct config_source {
 	int eof;
 	struct strbuf value;
 	struct strbuf var;
+	unsigned subsection_case_sensitive : 1;
 
 	int (*do_fgetc)(struct config_source *c);
 	int (*do_ungetc)(int c, struct config_source *conf);
@@ -603,6 +604,7 @@ static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 
 static int get_extended_base_var(struct strbuf *name, int c)
 {
+	cf->subsection_case_sensitive = 0;
 	do {
 		if (c == '\n')
 			goto error_incomplete_line;
@@ -639,6 +641,7 @@ static int get_extended_base_var(struct strbuf *name, int c)
 
 static int get_base_var(struct strbuf *name)
 {
+	cf->subsection_case_sensitive = 1;
 	for (;;) {
 		int c = get_next_char();
 		if (cf->eof)
@@ -2328,14 +2331,21 @@ static int store_aux_event(enum config_event_t type,
 	store->parsed[store->parsed_nr].type = type;
 
 	if (type == CONFIG_EVENT_SECTION) {
+		int (*cmpfn)(const char *, const char *, size_t);
+
 		if (cf->var.len < 2 || cf->var.buf[cf->var.len - 1] != '.')
 			return error("invalid section name '%s'", cf->var.buf);
 
+		if (cf->subsection_case_sensitive)
+			cmpfn = strncasecmp;
+		else
+			cmpfn = strncmp;
+
 		/* Is this the section we were looking for? */
 		store->is_keys_section =
 			store->parsed[store->parsed_nr].is_keys_section =
 			cf->var.len - 1 == store->baselen &&
-			!strncasecmp(cf->var.buf, store->key, store->baselen);
+			!cmpfn(cf->var.buf, store->key, store->baselen);
 		if (store->is_keys_section) {
 			store->section_seen = 1;
 			ALLOC_GROW(store->seen, store->seen_nr + 1,
diff --git a/t/t1300-config.sh b/t/t1300-config.sh
index c15c19bf78d..77c5899d000 100755
--- a/t/t1300-config.sh
+++ b/t/t1300-config.sh
@@ -1260,6 +1260,7 @@ test_expect_success 'setting different case sensitive subsections ' '
 		Qc = v2
 		[d "e"]
 		f = v1
+		[d "E"]
 		Qf = v2
 	EOF
 	# exact match
-- 
2.18.0.597.ga71716f1ad-goog

[PATCH 3/3] git-config: document accidental multi-line setting in deprecated syntax

[Stefan Beller]

The bug was noticed when writing the previous patch; a fix for this bug
is not easy though: If we choose to ignore the case of the subsection
(and revert most of the code of the previous patch, just keeping
s/strncasecmp/strcmp/), then we'd introduce new sections using the
new syntax, such that

 --------
   [section.subsection]
     key = value1
 --------

  git config section.Subsection.key value2

would result in

 --------
   [section.subsection]
     key = value1
   [section.Subsection]
     key = value2
 --------

which is even more confusing. A proper fix would replace the first
occurrence of 'key'. As the syntax is deprecated, let's prefer to not
spend time on fixing the behavior and just document it instead.

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 Documentation/git-config.txt | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
index 14da5fc157e..1ac2eab9482 100644
--- a/Documentation/git-config.txt
+++ b/Documentation/git-config.txt
@@ -430,6 +430,27 @@ http.sslverify false
 
 include::config.txt[]
 
+BUGS
+----
+When using the deprecated `[section.subsection]` syntax, changing a value
+will result in adding a multi-line key instead of a change, if the subsection
+is given with at least one uppercase character. For example when the config
+looks like
+
+--------
+  [section.subsection]
+    key = value1
+--------
+
+and running `git config section.Subsection.key value2` will result in
+
+--------
+  [section.subsection]
+    key = value1
+    key = value2
+--------
+
+
 GIT
 ---
 Part of the linkgit:git[1] suite
-- 
2.18.0.597.ga71716f1ad-goog

Re: [PATCH 0/3] Resending sb/config-write-fix

[Junio C Hamano]

Stefan Beller <sbeller@google.com> writes:

> This is a resend of sb/config-write-fix, with a slightly
> better commit message and a renamed variable.
>
> Thanks,
> Stefan

Thanks.  Let's declare victory and mark it to be merged to 'next'.