Re: [PATCH v2 7/7] rm: honor sparse checkout patterns

`git add` refrains from adding or updating paths outside the sparsity
rules, but `git rm` doesn't follow the same restrictions. This is
somewhat counter-intuitive and inconsistent. So make `rm` honor the
sparse checkout and advise on how to remove SKIP_WORKTREE entries, just
like `add` does. Also add some tests for the new behavior.

Suggested-by: Elijah Newren <redacted>
Signed-off-by: Matheus Tavares <redacted>
---
 Documentation/config/advice.txt  |  5 ++-
 Documentation/git-rm.txt         |  4 +-
 builtin/rm.c                     | 35 ++++++++++-----
 t/t3602-rm-sparse-checkout.sh    | 76 ++++++++++++++++++++++++++++++++
 t/t7011-skip-worktree-reading.sh |  5 ---
 5 files changed, 106 insertions(+), 19 deletions(-)
 create mode 100755 t/t3602-rm-sparse-checkout.sh

diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index d53eafa00b..bdd423ade4 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt

@@ -120,6 +120,7 @@ advice.*::
                Advice shown if a user runs the add command without providing
                the pathspec parameter.
        updateSparsePath::
-               Advice shown if the pathspec given to linkgit:git-add[1] only
-               matches index entries outside the current sparse-checkout.
+               Advice shown if the pathspec given to linkgit:git-add[1] or
+               linkgit:git-rm[1] only matches index entries outside the
+               current sparse-checkout.
 --

diff --git a/Documentation/git-rm.txt b/Documentation/git-rm.txt
index ab750367fd..26e9b28470 100644
--- a/Documentation/git-rm.txt
+++ b/Documentation/git-rm.txt

@@ -23,7 +23,9 @@ branch, and no updates to their contents can be staged in the index,
 though that default behavior can be overridden with the `-f` option.
 When `--cached` is given, the staged content has to
 match either the tip of the branch or the file on disk,
-allowing the file to be removed from just the index.
+allowing the file to be removed from just the index. When
+sparse-checkouts are in use (see linkgit:git-sparse-checkout[1]),
+`git rm` will only remove paths within the sparse-checkout patterns.


 OPTIONS

diff --git a/builtin/rm.c b/builtin/rm.c
index 4858631e0f..d23a3b2164 100644
--- a/builtin/rm.c
+++ b/builtin/rm.c

@@ -5,6 +5,7 @@
  */
 #define USE_THE_INDEX_COMPATIBILITY_MACROS
 #include "builtin.h"
+#include "advice.h"
 #include "config.h"
 #include "lockfile.h"
 #include "dir.h"

@@ -254,7 +255,7 @@ static struct option builtin_rm_options[] = {
 int cmd_rm(int argc, const char **argv, const char *prefix)
 {
        struct lock_file lock_file = LOCK_INIT;
-       int i;
+       int i, ret = 0;
        struct pathspec pathspec;
        char *seen;

@@ -295,6 +296,8 @@ int cmd_rm(int argc, const char **argv, const char *prefix)

        for (i = 0; i < active_nr; i++) {
                const struct cache_entry *ce = active_cache[i];
+               if (ce_skip_worktree(ce))
+                       continue;
                if (!ce_path_match(&the_index, ce, &pathspec, seen))
                        continue;
                ALLOC_GROW(list.entry, list.nr + 1, list.alloc);

@@ -308,24 +311,34 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
        if (pathspec.nr) {
                const char *original;
                int seen_any = 0;
+               char *skip_worktree_seen = NULL;
+               struct string_list only_match_skip_worktree = STRING_LIST_INIT_NODUP;
+
                for (i = 0; i < pathspec.nr; i++) {
                        original = pathspec.items[i].original;
-                       if (!seen[i]) {
-                               if (!ignore_unmatch) {
-                                       die(_("pathspec '%s' did not match any files"),
-                                           original);
-                               }
-                       }
-                       else {
+                       if (seen[i])
                                seen_any = 1;
-                       }
+                       else if (ignore_unmatch)
+                               continue;
+                       else if (matches_skip_worktree(&pathspec, i, &skip_worktree_seen))
+                               string_list_append(&only_match_skip_worktree, original);
+                       else
+                               die(_("pathspec '%s' did not match any files"), original);
+
                        if (!recursive && seen[i] == MATCHED_RECURSIVELY)
                                die(_("not removing '%s' recursively without -r"),
                                    *original ? original : ".");
                }

+               if (only_match_skip_worktree.nr) {
+                       advise_on_updating_sparse_paths(&only_match_skip_worktree);
+                       ret = 1;
+               }
+               free(skip_worktree_seen);
+               string_list_clear(&only_match_skip_worktree, 0);
+
                if (!seen_any)
-                       exit(0);
+                       exit(ret);
        }

        if (!index_only)

@@ -405,5 +418,5 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
                               COMMIT_LOCK | SKIP_IF_UNCHANGED))
                die(_("Unable to write new index file"));

-       return 0;
+       return ret;
 }

diff --git a/t/t3602-rm-sparse-checkout.sh b/t/t3602-rm-sparse-checkout.sh
new file mode 100755
index 0000000000..34f4debacf
--- /dev/null
+++ b/t/t3602-rm-sparse-checkout.sh

@@ -0,0 +1,76 @@
+#!/bin/sh
+
+test_description='git rm in sparse checked out working trees'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+       mkdir -p sub/dir &&
+       touch a b c sub/d sub/dir/e &&
+       git add -A &&
+       git commit -m files &&
+
+       cat >sparse_entry_b_error <<-EOF &&
+       The following pathspecs only matched index entries outside the current
+       sparse checkout:
+       b
+       EOF
+
+       cat >b_error_and_hint sparse_entry_b_error - <<-EOF
+       hint: Disable or modify the sparsity rules if you intend to update such entries.
+       hint: Disable this message with "git config advice.updateSparsePath false"
+       EOF
+'
+
+for opt in "" -f --dry-run
+do
+       test_expect_success "rm${opt:+ $opt} does not remove sparse entries" '
+               git sparse-checkout set a &&
+               test_must_fail git rm $opt b 2>stderr &&
+               test_i18ncmp b_error_and_hint stderr &&
+               git ls-files --error-unmatch b
+       '
+done
+
+test_expect_success 'recursive rm does not remove sparse entries' '
+       git reset --hard &&
+       git sparse-checkout set sub/dir &&
+       git rm -r sub &&
+       git status --porcelain -uno >actual &&
+       echo "D  sub/dir/e" >expected &&
+       test_cmp expected actual
+'
+
+test_expect_success 'rm obeys advice.updateSparsePath' '
+       git reset --hard &&
+       git sparse-checkout set a &&
+       test_must_fail git -c advice.updateSparsePath=false rm b 2>stderr &&
+       test_i18ncmp sparse_entry_b_error stderr
+'
+
+test_expect_success 'do not advice about sparse entries when they do not match the pathspec' '
+       git reset --hard &&
+       git sparse-checkout set a &&
+       test_must_fail git rm nonexistent 2>stderr &&
+       test_i18ngrep "fatal: pathspec .nonexistent. did not match any files" stderr &&
+       test_i18ngrep ! "The following pathspecs only matched index entries" stderr
+'
+
+test_expect_success 'do not warn about sparse entries when pathspec matches dense entries' '
+       git reset --hard &&
+       git sparse-checkout set a &&
+       git rm "[ba]" 2>stderr &&
+       test_must_be_empty stderr &&
+       git ls-files --error-unmatch b &&
+       test_must_fail git ls-files --error-unmatch a
+'
+
+test_expect_success 'do not warn about sparse entries with --ignore-unmatch' '
+       git reset --hard &&
+       git sparse-checkout set a &&
+       git rm --ignore-unmatch b 2>stderr &&
+       test_must_be_empty stderr &&
+       git ls-files --error-unmatch b
+'
+
+test_done

diff --git a/t/t7011-skip-worktree-reading.sh b/t/t7011-skip-worktree-reading.sh
index 37525cae3a..f87749951f 100755
--- a/t/t7011-skip-worktree-reading.sh
+++ b/t/t7011-skip-worktree-reading.sh

@@ -141,11 +141,6 @@ test_expect_success 'diff-files does not examine skip-worktree dirty entries' '
        test -z "$(git diff-files -- one)"
 '

-test_expect_success 'git-rm succeeds on skip-worktree absent entries' '
-       setup_absent &&
-       git rm 1
-'
-
 test_expect_success 'commit on skip-worktree absent entries' '
        git reset &&
        setup_absent &&
--

2.30.1