[PATCH v4 16/18] Add --full-line-diff option

[Bo Yang <struggleyb.nku@gmail.com>]

Always print the interesting ranges even if the current
commit does not change any line of it.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
---
 builtin/log.c |    3 +++
 line.c        |   21 +++++++++++++++------
 revision.c    |    5 ++++-
 revision.h    |    3 ++-
 4 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/builtin/log.c b/builtin/log.c
index 0aa982b..9799c1c 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -86,6 +86,7 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 {
 	int i;
 	int decoration_given = 0;
+	static int full_line_diff = 0;
 	struct userformat_want w;
 	const char *path = NULL, *pathspec = NULL;
 	static struct diff_line_range *range = NULL, *r = NULL;
@@ -93,6 +94,7 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 	static struct line_opt_callback_data line_cb = {&range, &ctx, NULL};
 	static const struct option options[] = {
 		OPT_CALLBACK('L', NULL, &line_cb, "n,m", "Process only line range n,m, counting from 1", log_line_range_callback),
+		OPT_BOOLEAN(0, "full-line-diff", &full_line_diff, "Always print the interesting range even if the current commit does not change any line of it"),
 		OPT_END()
 	};
 
@@ -225,6 +227,7 @@ parse_done:
 	/* Test whether line level history is asked for */
 	if (range && range->nr > 0) {
 		setup_line(rev, range);
+		rev->full_line_diff = full_line_diff;
 	}
 }
 
diff --git a/line.c b/line.c
index 7d80da8..7ab0341 100644
--- a/line.c
+++ b/line.c
@@ -1255,9 +1255,16 @@ static void diff_flush_filepair(struct rev_info *rev, struct diff_line_range *ra
 	/*
 	 * the ranges that touch no different file, in this case
 	 * the line number will not change, and of course we have
-	 * no sensible rang->pair since there is no diff run.
+	 * no sensible range->pair since there is no diff run.
 	 */
 	if (one == NULL) {
+		if (rev->full_line_diff) {
+			chunk.two = two->data;
+			chunk.two_end = two->data + two->size;
+			chunk.ltwo = 1;
+			chunk.range = range;
+			diff_flush_chunks(&rev->diffopt, &chunk);
+		}
 		return;
 	}
 
@@ -1378,8 +1385,9 @@ static void line_log_flush(struct rev_info *rev, struct commit *c)
 	char *line_prefix = "";
 	struct strbuf *msgbuf;
 
-	if (range == NULL || ! (c->object.flags & NONTRIVIAL_MERGE ||
-							c->object.flags & NEED_PRINT))
+	if (range == NULL || !(c->object.flags & NONTRIVIAL_MERGE ||
+			c->object.flags & NEED_PRINT ||
+			rev->full_line_diff))
 		return;
 
 	if (rev->graph)
@@ -1400,7 +1408,7 @@ static void line_log_flush(struct rev_info *rev, struct commit *c)
 		flush_nontrivial_merge(rev, nontrivial);
 	else {
 		while (range) {
-			if (range->diff)
+			if (range->diff || (range->nr && rev->full_line_diff))
 				diff_flush_filepair(rev, range);
 			range = range->next;
 		}
@@ -1432,7 +1440,7 @@ int cmd_line_log_walk(struct rev_info *rev)
 	/* Clear the flags */
 	while (list && !limited) {
 		list->item->object.flags &= ~(RANGE_UPDATE | NONTRIVIAL_MERGE |
-						NEED_PRINT | EVIL_MERGE);
+				NEED_PRINT | EVIL_MERGE);
 		list = list->next;
 	}
 
@@ -1446,7 +1454,8 @@ int cmd_line_log_walk(struct rev_info *rev)
 		}
 
 		if (commit->object.flags & NEED_PRINT ||
-			commit->object.flags & NONTRIVIAL_MERGE || rev->graph) {
+			commit->object.flags & NONTRIVIAL_MERGE ||
+			rev->full_line_diff) {
 			line_log_flush(rev, commit);
 		}
 
diff --git a/revision.c b/revision.c
index a6527ca..62fe002 100644
--- a/revision.c
+++ b/revision.c
@@ -1887,7 +1887,10 @@ int prepare_revision_walk(struct rev_info *revs)
 			return -1;
 	if (revs->topo_order)
 		sort_in_topological_order(&revs->commits, revs->lifo);
-	if (revs->rewrite_parents && revs->line_level_traverse)
+	if (revs->full_line_diff)
+		revs->dense = 0;
+	if (revs->rewrite_parents && revs->line_level_traverse
+		&& !revs->full_line_diff)
 		limit_list_line(revs);
 	if (revs->simplify_merges)
 		simplify_merges(revs);
diff --git a/revision.h b/revision.h
index 7f7d178..db901e5 100644
--- a/revision.h
+++ b/revision.h
@@ -73,7 +73,8 @@ struct rev_info {
 			bisect:1,
 			ancestry_path:1,
 			first_parent_only:1,
-			line_level_traverse:1;
+			line_level_traverse:1,
+			full_line_diff:1;
 
 	/* Diff flags */
 	unsigned int	diff:1,
-- 
1.7.2.20.g388bbb