From 0f5a1d449b9538c2765de9d6683abbb83a7fb4e2 Mon Sep 17 00:00:00 2001 From: Denton Liu Date: Sun, 20 Sep 2020 04:22:25 -0700 Subject: builtin/diff-index: learn --merge-base There is currently no easy way to take the diff between the working tree or index and the merge base between an arbitrary commit and HEAD. Even diff's `...` notation doesn't allow this because it only works between commits. However, the ability to do this would be desirable to a user who would like to see all the changes they've made on a branch plus uncommitted changes without taking into account changes made in the upstream branch. Teach diff-index and diff (with one commit) the --merge-base option which allows a user to use the merge base of a commit and HEAD as the "before" side. Signed-off-by: Denton Liu Signed-off-by: Junio C Hamano diff --git a/Documentation/git-diff-index.txt b/Documentation/git-diff-index.txt index 25fe165..27acb31 100644 --- a/Documentation/git-diff-index.txt +++ b/Documentation/git-diff-index.txt @@ -9,7 +9,7 @@ git-diff-index - Compare a tree to the working tree or index SYNOPSIS -------- [verse] -'git diff-index' [-m] [--cached] [] [...] +'git diff-index' [-m] [--cached] [--merge-base] [] [...] DESCRIPTION ----------- @@ -29,6 +29,11 @@ include::diff-options.txt[] --cached:: Do not consider the on-disk file at all. +--merge-base:: + Instead of comparing directly, use the merge base + between and HEAD instead. must be a + commit. + -m:: By default, files recorded in the index but not checked out are reported as deleted. This flag makes diff --git a/Documentation/git-diff.txt b/Documentation/git-diff.txt index 8f7b4ed..762ee6d 100644 --- a/Documentation/git-diff.txt +++ b/Documentation/git-diff.txt @@ -10,7 +10,7 @@ SYNOPSIS -------- [verse] 'git diff' [] [] [--] [...] -'git diff' [] --cached [] [--] [...] +'git diff' [] --cached [--merge-base] [] [--] [...] 'git diff' [] [...] [--] [...] 'git diff' [] ... [--] [...] 'git diff' [] @@ -40,7 +40,7 @@ files on disk. or when running the command outside a working tree controlled by Git. This form implies `--exit-code`. -'git diff' [] --cached [] [--] [...]:: +'git diff' [] --cached [--merge-base] [] [--] [...]:: This form is to view the changes you staged for the next commit relative to the named . Typically you @@ -49,6 +49,10 @@ files on disk. If HEAD does not exist (e.g. unborn branches) and is not given, it shows all staged changes. --staged is a synonym of --cached. ++ +If --merge-base is given, instead of using , use the merge base +of and HEAD. `git diff --merge-base A` is equivalent to +`git diff $(git merge-base A HEAD)`. 'git diff' [] [--] [...]:: @@ -89,8 +93,8 @@ files on disk. Just in case you are doing something exotic, it should be noted that all of the in the above description, except -in the last two forms that use `..` notations, can be any -. +in the `--merge-base` case and in the last two forms that use `..` +notations, can be any . For a more complete list of ways to spell , see "SPECIFYING REVISIONS" section in linkgit:gitrevisions[7]. diff --git a/builtin/diff-index.c b/builtin/diff-index.c index c3878f7..7f5281c 100644 --- a/builtin/diff-index.c +++ b/builtin/diff-index.c @@ -33,6 +33,8 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix) if (!strcmp(arg, "--cached")) option |= DIFF_INDEX_CACHED; + else if (!strcmp(arg, "--merge-base")) + option |= DIFF_INDEX_MERGE_BASE; else usage(diff_cache_usage); } diff --git a/builtin/diff.c b/builtin/diff.c index e45e19e..1baea18 100644 --- a/builtin/diff.c +++ b/builtin/diff.c @@ -139,6 +139,8 @@ static int builtin_diff_index(struct rev_info *revs, const char *arg = argv[1]; if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged")) option |= DIFF_INDEX_CACHED; + else if (!strcmp(arg, "--merge-base")) + option |= DIFF_INDEX_MERGE_BASE; else usage(builtin_diff_usage); argv++; argc--; diff --git a/diff-lib.c b/diff-lib.c index 468e3fe..c578560 100644 --- a/diff-lib.c +++ b/diff-lib.c @@ -561,13 +561,26 @@ int run_diff_index(struct rev_info *revs, unsigned int option) { struct object_array_entry *ent; int cached = !!(option & DIFF_INDEX_CACHED); + int merge_base = !!(option & DIFF_INDEX_MERGE_BASE); + struct object_id oid; + const char *name; + char merge_base_hex[GIT_MAX_HEXSZ + 1]; if (revs->pending.nr != 1) BUG("run_diff_index must be passed exactly one tree"); trace_performance_enter(); ent = revs->pending.objects; - if (diff_cache(revs, &ent->item->oid, ent->name, cached)) + + if (merge_base) { + diff_get_merge_base(revs, &oid); + name = oid_to_hex_r(merge_base_hex, &oid); + } else { + oidcpy(&oid, &ent->item->oid); + name = ent->name; + } + + if (diff_cache(revs, &oid, name, cached)) exit(128); diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/"); diff --git a/diff.h b/diff.h index fedfeab..6c2efa1 100644 --- a/diff.h +++ b/diff.h @@ -589,6 +589,7 @@ void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb); int run_diff_files(struct rev_info *revs, unsigned int option); #define DIFF_INDEX_CACHED 01 +#define DIFF_INDEX_MERGE_BASE 02 int run_diff_index(struct rev_info *revs, unsigned int option); int do_diff_cache(const struct object_id *, struct diff_options *); diff --git a/t/t4068-diff-symmetric-merge-base.sh b/t/t4068-diff-symmetric-merge-base.sh index bd4cf25..4943237 100755 --- a/t/t4068-diff-symmetric-merge-base.sh +++ b/t/t4068-diff-symmetric-merge-base.sh @@ -97,4 +97,63 @@ test_expect_success 'diff --merge-base with three commits' ' test_i18ngrep "usage" err ' +for cmd in diff-index diff +do + test_expect_success "$cmd --merge-base with one commit" ' + git checkout master && + git $cmd commit-C >expect && + git $cmd --merge-base br2 >actual && + test_cmp expect actual + ' + + test_expect_success "$cmd --merge-base with one commit and unstaged changes" ' + git checkout master && + test_when_finished git reset --hard && + echo unstaged >>c && + git $cmd commit-C >expect && + git $cmd --merge-base br2 >actual && + test_cmp expect actual + ' + + test_expect_success "$cmd --merge-base with one commit and staged and unstaged changes" ' + git checkout master && + test_when_finished git reset --hard && + echo staged >>c && + git add c && + echo unstaged >>c && + git $cmd commit-C >expect && + git $cmd --merge-base br2 >actual && + test_cmp expect actual + ' + + test_expect_success "$cmd --merge-base --cached with one commit and staged and unstaged changes" ' + git checkout master && + test_when_finished git reset --hard && + echo staged >>c && + git add c && + echo unstaged >>c && + git $cmd --cached commit-C >expect && + git $cmd --cached --merge-base br2 >actual && + test_cmp expect actual + ' + + test_expect_success "$cmd --merge-base with non-commit" ' + git checkout master && + test_must_fail git $cmd --merge-base master^{tree} 2>err && + test_i18ngrep "fatal: --merge-base only works with commits" err + ' + + test_expect_success "$cmd --merge-base with no merge bases and one commit" ' + git checkout master && + test_must_fail git $cmd --merge-base br3 2>err && + test_i18ngrep "fatal: no merge base found" err + ' + + test_expect_success "$cmd --merge-base with multiple merge bases and one commit" ' + git checkout master && + test_must_fail git $cmd --merge-base br1 2>err && + test_i18ngrep "fatal: multiple merge bases found" err + ' +done + test_done -- cgit v0.10.2-6-g49f6