From 0133dab75d8b15c559aa9df66134d72dce0e0476 Mon Sep 17 00:00:00 2001 From: Johan Herland Date: Mon, 11 Apr 2011 00:48:51 +0200 Subject: [PATCH] --dirstat-by-file: Make it faster and more correct Currently, when using --dirstat-by-file, it first does the full --dirstat analysis (using diffcore_count_changes()), and then resets 'damage' to 1, if any damage was found by diffcore_count_changes(). But --dirstat-by-file is not interested in the file damage per se. It only cares if the file changed at all. In that sense it only cares if the blob object for a file has changed. We therefore only need to compare the object names of each file pair in the diff queue and we can skip the entire --dirstat analysis and simply set 'damage' to 1 for each entry where the object name has changed. This makes --dirstat-by-file faster, and also bypasses --dirstat's practice of ignoring rearranged lines within a file. The patch also contains an added testcase verifying that --dirstat-by-file now detects changes that only rearrange lines within a file. Signed-off-by: Johan Herland Acked-by: Linus Torvalds Signed-off-by: Junio C Hamano --- diff.c | 25 +++++++++++++++---- t/t4013-diff-various.sh | 2 ++ ...f.diff_--dirstat-by-file_initial_rearrange | 3 +++ 3 files changed, 25 insertions(+), 5 deletions(-) create mode 100644 t/t4013/diff.diff_--dirstat-by-file_initial_rearrange diff --git a/diff.c b/diff.c index 3fd9e0c70..4f5270b8d 100644 --- a/diff.c +++ b/diff.c @@ -1539,9 +1539,27 @@ static void show_dirstat(struct diff_options *options) struct diff_filepair *p = q->queue[i]; const char *name; unsigned long copied, added, damage; + int content_changed; name = p->one->path ? p->one->path : p->two->path; + if (p->one->sha1_valid && p->two->sha1_valid) + content_changed = hashcmp(p->one->sha1, p->two->sha1); + else + content_changed = 1; + + if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE)) { + /* + * In --dirstat-by-file mode, we don't really need to + * look at the actual file contents at all. + * The fact that the SHA1 changed is enough for us to + * add this file to the list of results + * (with each file contributing equal damage). + */ + damage = content_changed ? 1 : 0; + goto found_damage; + } + if (DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) { diff_populate_filespec(p->one, 0); diff_populate_filespec(p->two, 0); @@ -1564,14 +1582,11 @@ static void show_dirstat(struct diff_options *options) /* * Original minus copied is the removed material, * added is the new material. They are both damages - * made to the preimage. In --dirstat-by-file mode, count - * damaged files, not damaged lines. This is done by - * counting only a single damaged line per file. + * made to the preimage. */ damage = (p->one->size - copied) + added; - if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0) - damage = 1; +found_damage: ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc); dir.files[dir.nr].name = name; dir.files[dir.nr].changed = damage; diff --git a/t/t4013-diff-various.sh b/t/t4013-diff-various.sh index 3b1b392a5..6428a905a 100755 --- a/t/t4013-diff-various.sh +++ b/t/t4013-diff-various.sh @@ -302,6 +302,8 @@ diff master master^ side diff --dirstat master~1 master~2 # --dirstat doesn't notice changes that simply rearrange existing lines diff --dirstat initial rearrange +# ...but --dirstat-by-file does notice changes that only rearrange lines +diff --dirstat-by-file initial rearrange EOF test_expect_success 'log -S requires an argument' ' diff --git a/t/t4013/diff.diff_--dirstat-by-file_initial_rearrange b/t/t4013/diff.diff_--dirstat-by-file_initial_rearrange new file mode 100644 index 000000000..e48e33f67 --- /dev/null +++ b/t/t4013/diff.diff_--dirstat-by-file_initial_rearrange @@ -0,0 +1,3 @@ +$ git diff --dirstat-by-file initial rearrange + 100.0% dir/ +$ -- 2.26.2