git/combine-diff.c, branch v2.37.2

Merge branch 'rs/combine-diff-with-incompatible-options' into maint

2022-07-27T20:00:32Z

Certain diff options are currently ignored when combined-diff is shown; mark them as incompatible with the feature. source: <220524.86v8tuvfl1.gmgdl@evledraar.gmail.com> * rs/combine-diff-with-incompatible-options: combine-diff: abort if --output is given combine-diff: abort if --ignore-matching-lines is given

combine-diff: abort if --output is given

2022-06-21T16:56:33Z

The code for combined diffs currently only writes to stdout. Abort and report that fact instead of silently ignoring the --output option. The (empty) output file has already been created at that point, though. Reported-by: Ævar Arnfjörð Bjarmason Signed-off-by: René Scharfe Signed-off-by: Junio C Hamano

combine-diff: abort if --ignore-matching-lines is given

2022-06-21T16:56:30Z

The code for combined diffs doesn't currently support ignoring changes that match a regex. Abort and report that fact instead of running into a segfault. Signed-off-by: René Scharfe Signed-off-by: Junio C Hamano

tree-wide: apply equals-null.cocci

2022-05-02T16:50:37Z

Signed-off-by: Junio C Hamano

Merge branch 'ab/pickaxe-pcre2'

2021-07-13T23:52:50Z

Rewrite the backend for "diff -G/-S" to use pcre2 engine when available. * ab/pickaxe-pcre2: (22 commits) xdiff-interface: replace discard_hunk_line() with a flag xdiff users: use designated initializers for out_line pickaxe -G: don't special-case create/delete pickaxe -G: terminate early on matching lines xdiff-interface: allow early return from xdiff_emit_line_fn xdiff-interface: prepare for allowing early return pickaxe -S: slightly optimize contains() pickaxe: rename variables in has_changes() for brevity pickaxe -S: support content with NULs under --pickaxe-regex pickaxe: assert that we must have a needle under -G or -S pickaxe: refactor function selection in diffcore-pickaxe() perf: add performance test for pickaxe pickaxe/style: consolidate declarations and assignments diff.h: move pickaxe fields together again pickaxe: die when --find-object and --pickaxe-all are combined pickaxe: die when -G and --pickaxe-regex are combined pickaxe tests: add missing test for --no-pickaxe-regex being an error pickaxe tests: test for -G, -S and --find-object incompatibility pickaxe tests: add test for "log -S" not being a regex pickaxe tests: add test for diffgrep_consume() internals ...

xdiff-interface: prepare for allowing early return

2021-05-11T03:47:31Z

Change the function prototype of xdiff_emit_line_fn to return an "int" instead of "void". Change all of those functions to "return 0", nothing checks those return values yet, and no behavior is being changed. In subsequent commits the interface will be changed to allow early return via this new return value. Signed-off-by: Ævar Arnfjörð Bjarmason Signed-off-by: Junio C Hamano

hash: provide per-algorithm null OIDs

2021-04-27T07:31:39Z

Up until recently, object IDs did not have an algorithm member, only a hash. Consequently, it was possible to share one null (all-zeros) object ID among all hash algorithms. Now that we're going to be handling objects from multiple hash algorithms, it's important to make sure that all object IDs have a correct algorithm field. Introduce a per-algorithm null OID, and add it to struct hash_algo. Introduce a wrapper function as well, and use it everywhere we used to use the null_oid constant. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

use CALLOC_ARRAY

2021-03-14T00:00:09Z

Add and apply a semantic patch for converting code that open-codes CALLOC_ARRAY to use it instead. It shortens the code and infers the element size automatically. Signed-off-by: René Scharfe Signed-off-by: Junio C Hamano

Merge branch 'jk/diff-cc-oidfind-fix'

2020-10-05T21:01:55Z

"log -c --find-object=X" did not work well to find a merge that involves a change to an object X from only one parent. * jk/diff-cc-oidfind-fix: combine-diff: handle --find-object in multitree code path

combine-diff: handle --find-object in multitree code path

2020-09-30T20:35:24Z

When doing combined diffs, we have two possible code paths: - a slower one which independently diffs against each parent, applies any filters, and then intersects the resulting paths - a faster one which walks all trees simultaneously When the diff options specify that we must do certain filters, like pickaxe, then we always use the slow path, since the pickaxe code only knows how to handle filepairs, not the n-parent entries generated for combined diffs. But there are two problems with the slow path: 1. It's slow. Running: git rev-list HEAD | git diff-tree --stdin -r -c in git.git takes ~3s on my machine. But adding "--find-object" to that increases it to ~6s, even though find-object itself should incur only a few extra oid comparisons. On linux.git, it's even worse: 35s versus 215s. 2. It doesn't catch all cases where a particular path is interesting. Consider a merge with parent blobs X and Y for a particular path, and end result Z. That should be interesting according to "-c", because the result doesn't match either parent. And it should be interesting even with "--find-object=X", because "X" went away in the merge. But because we perform each pairwise diff independently, this confuses the intersection code. The change from X to Z is still interesting according to --find-object. But in the other parent we went from Y to Z, so the diff appears empty! That causes the intersection code to think that parent didn't change the path, and thus it's not interesting for "-c". This patch fixes both by implementing --find-object for the multitree code. It's a bit unfortunate that we have to duplicate some logic from diffcore-pickaxe, but this is the best we can do for now. In an ideal world, all of the diffcore code would stop thinking about filepairs and start thinking about n-parent sets, and we could use the multitree walk with all of it. Until then, there are some leftover warts: - other pickaxe operations, like -S or -G, still suffer from both problems. These would be hard to adapt because they rely on having a diff_filespec() for each path to look at content. And we'd need to define what an n-way "change" means in each case (probably easy for "-S", which can compare counts, but not so clear for -G, which is about grepping diffs). - other options besides --find-object may cause us to use the slow pairwise path, in which case we'll go back to producing a different (wrong) answer for the X/Y/Z case above. We may be able to hack around these, but I think the ultimate solution will be a larger rewrite of the diffcore code. For now, this patch improves one specific case but leaves the rest. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano