Merge branch 'mt/add-rm-in-sparse-checkout'

"git add" and "git rm" learned not to touch those paths that are
outside of sparse checkout.

* mt/add-rm-in-sparse-checkout:
  rm: honor sparse checkout patterns
  add: warn when asked to update SKIP_WORKTREE entries
  refresh_index(): add flag to ignore SKIP_WORKTREE entries
  pathspec: allow to ignore SKIP_WORKTREE entries on index matching
  add: make --chmod and --renormalize honor sparse checkouts
  t3705: add tests for `git add` in sparse checkouts
  add: include magic part of pathspec on --refresh error

16 files changed, 408 insertions, 63 deletions

diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index acbd0c09aa..8b2849ff7b 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -119,4 +119,8 @@ advice.*::
 	addEmptyPathspec::
 		Advice shown if a user runs the add command without providing
 		the pathspec parameter.
+	updateSparsePath::
+		Advice shown when either linkgit:git-add[1] or linkgit:git-rm[1]
+		is asked to update 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/advice.c b/advice.c
index 164742305f..0b9c89c48a 100644
--- a/advice.c
+++ b/advice.c
@@ -2,6 +2,7 @@
 #include "config.h"
 #include "color.h"
 #include "help.h"
+#include "string-list.h"
 
 int advice_fetch_show_forced_updates = 1;
 int advice_push_update_rejected = 1;
@@ -136,6 +137,7 @@ static struct {
 	[ADVICE_STATUS_HINTS]				= { "statusHints", 1 },
 	[ADVICE_STATUS_U_OPTION]			= { "statusUoption", 1 },
 	[ADVICE_SUBMODULE_ALTERNATE_ERROR_STRATEGY_DIE] = { "submoduleAlternateErrorStrategyDie", 1 },
+	[ADVICE_UPDATE_SPARSE_PATH]			= { "updateSparsePath", 1 },
 	[ADVICE_WAITING_FOR_EDITOR]			= { "waitingForEditor", 1 },
 };
 
@@ -284,6 +286,24 @@ void NORETURN die_conclude_merge(void)
 	die(_("Exiting because of unfinished merge."));
 }
 
+void advise_on_updating_sparse_paths(struct string_list *pathspec_list)
+{
+	struct string_list_item *item;
+
+	if (!pathspec_list->nr)
+		return;
+
+	fprintf(stderr, _("The following pathspecs didn't match any"
+			  " eligible path, but they do match index\n"
+			  "entries outside the current sparse checkout:\n"));
+	for_each_string_list_item(item, pathspec_list)
+		fprintf(stderr, "%s\n", item->string);
+
+	advise_if_enabled(ADVICE_UPDATE_SPARSE_PATH,
+			  _("Disable or modify the sparsity rules if you intend"
+			    " to update such entries."));
+}
+
 void detach_advice(const char *new_name)
 {
 	const char *fmt =
diff --git a/advice.h b/advice.h
index bc2432980a..bd26c385d0 100644
--- a/advice.h
+++ b/advice.h
@@ -3,6 +3,8 @@
 
 #include "git-compat-util.h"
 
+struct string_list;
+
 extern int advice_fetch_show_forced_updates;
 extern int advice_push_update_rejected;
 extern int advice_push_non_ff_current;
@@ -71,6 +73,7 @@ extern int advice_add_empty_pathspec;
 	ADVICE_STATUS_HINTS,
 	ADVICE_STATUS_U_OPTION,
 	ADVICE_SUBMODULE_ALTERNATE_ERROR_STRATEGY_DIE,
+	ADVICE_UPDATE_SPARSE_PATH,
 	ADVICE_WAITING_FOR_EDITOR,
 };
 
@@ -92,6 +95,7 @@ void advise_if_enabled(enum advice_type type, const char *advice, ...);
 int error_resolve_conflict(const char *me);
 void NORETURN die_resolve_conflict(const char *me);
 void NORETURN die_conclude_merge(void);
+void advise_on_updating_sparse_paths(struct string_list *pathspec_list);
 void detach_advice(const char *new_name);
 
 #endif /* ADVICE_H */
diff --git a/builtin/add.c b/builtin/add.c
index afccf2fd55..58ee3f954e 100644
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -46,6 +46,9 @@ static int chmod_pathspec(struct pathspec *pathspec, char flip, int show_only)
 		struct cache_entry *ce = active_cache[i];
 		int err;
 
+		if (ce_skip_worktree(ce))
+			continue;
+
 		if (pathspec && !ce_path_match(&the_index, ce, pathspec, NULL))
 			continue;
 
@@ -146,6 +149,8 @@ static int renormalize_tracked_files(const struct pathspec *pathspec, int flags)
 	for (i = 0; i < active_nr; i++) {
 		struct cache_entry *ce = active_cache[i];
 
+		if (ce_skip_worktree(ce))
+			continue;
 		if (ce_stage(ce))
 			continue; /* do not touch unmerged paths */
 		if (!S_ISREG(ce->ce_mode) && !S_ISLNK(ce->ce_mode))
@@ -174,24 +179,44 @@ static char *prune_directory(struct dir_struct *dir, struct pathspec *pathspec,
 			*dst++ = entry;
 	}
 	dir->nr = dst - dir->entries;
-	add_pathspec_matches_against_index(pathspec, &the_index, seen);
+	add_pathspec_matches_against_index(pathspec, &the_index, seen,
+					   PS_IGNORE_SKIP_WORKTREE);
 	return seen;
 }
 
-static void refresh(int verbose, const struct pathspec *pathspec)
+static int refresh(int verbose, const struct pathspec *pathspec)
 {
 	char *seen;
-	int i;
+	int i, ret = 0;
+	char *skip_worktree_seen = NULL;
+	struct string_list only_match_skip_worktree = STRING_LIST_INIT_NODUP;
+	int flags = REFRESH_IGNORE_SKIP_WORKTREE |
+		    (verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET);
 
 	seen = xcalloc(pathspec->nr, 1);
-	refresh_index(&the_index, verbose ? REFRESH_IN_PORCELAIN : REFRESH_QUIET,
-		      pathspec, seen, _("Unstaged changes after refreshing the index:"));
+	refresh_index(&the_index, flags, pathspec, seen,
+		      _("Unstaged changes after refreshing the index:"));
 	for (i = 0; i < pathspec->nr; i++) {
-		if (!seen[i])
-			die(_("pathspec '%s' did not match any files"),
-			    pathspec->items[i].match);
+		if (!seen[i]) {
+			if (matches_skip_worktree(pathspec, i, &skip_worktree_seen)) {
+				string_list_append(&only_match_skip_worktree,
+						   pathspec->items[i].original);
+			} else {
+				die(_("pathspec '%s' did not match any files"),
+				    pathspec->items[i].original);
+			}
+		}
+	}
+
+	if (only_match_skip_worktree.nr) {
+		advise_on_updating_sparse_paths(&only_match_skip_worktree);
+		ret = 1;
 	}
+
 	free(seen);
+	free(skip_worktree_seen);
+	string_list_clear(&only_match_skip_worktree, 0);
+	return ret;
 }
 
 int run_add_interactive(const char *revision, const char *patch_mode,
@@ -567,15 +592,18 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 	}
 
 	if (refresh_only) {
-		refresh(verbose, &pathspec);
+		exit_status |= refresh(verbose, &pathspec);
 		goto finish;
 	}
 
 	if (pathspec.nr) {
 		int i;
+		char *skip_worktree_seen = NULL;
+		struct string_list only_match_skip_worktree = STRING_LIST_INIT_NODUP;
 
 		if (!seen)
-			seen = find_pathspecs_matching_against_index(&pathspec, &the_index);
+			seen = find_pathspecs_matching_against_index(&pathspec,
+					&the_index, PS_IGNORE_SKIP_WORKTREE);
 
 		/*
 		 * file_exists() assumes exact match
@@ -589,12 +617,24 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 
 		for (i = 0; i < pathspec.nr; i++) {
 			const char *path = pathspec.items[i].match;
+
 			if (pathspec.items[i].magic & PATHSPEC_EXCLUDE)
 				continue;
-			if (!seen[i] && path[0] &&
-			    ((pathspec.items[i].magic &
-			      (PATHSPEC_GLOB | PATHSPEC_ICASE)) ||
-			     !file_exists(path))) {
+			if (seen[i])
+				continue;
+
+			if (matches_skip_worktree(&pathspec, i, &skip_worktree_seen)) {
+				string_list_append(&only_match_skip_worktree,
+						   pathspec.items[i].original);
+				continue;
+			}
+
+			/* Don't complain at 'git add .' on empty repo */
+			if (!path[0])
+				continue;
+
+			if ((pathspec.items[i].magic & (PATHSPEC_GLOB | PATHSPEC_ICASE)) ||
+			    !file_exists(path)) {
 				if (ignore_missing) {
 					int dtype = DT_UNKNOWN;
 					if (is_excluded(&dir, &the_index, path, &dtype))
@@ -605,7 +645,16 @@ int cmd_add(int argc, const char **argv, const char *prefix)
 					    pathspec.items[i].original);
 			}
 		}
+
+
+		if (only_match_skip_worktree.nr) {
+			advise_on_updating_sparse_paths(&only_match_skip_worktree);
+			exit_status = 1;
+		}
+
 		free(seen);
+		free(skip_worktree_seen);
+		string_list_clear(&only_match_skip_worktree, 0);
 	}
 
 	plug_bulk_checkin();
diff --git a/builtin/check-ignore.c b/builtin/check-ignore.c
index 3c652748d5..0f4480a11b 100644
--- a/builtin/check-ignore.c
+++ b/builtin/check-ignore.c
@@ -100,7 +100,8 @@ static int check_ignore(struct dir_struct *dir,
 	 * should not be ignored, in order to be consistent with
 	 * 'git status', 'git add' etc.
 	 */
-	seen = find_pathspecs_matching_against_index(&pathspec, &the_index);
+	seen = find_pathspecs_matching_against_index(&pathspec, &the_index,
+						     PS_HEED_SKIP_WORKTREE);
 	for (i = 0; i < pathspec.nr; i++) {
 		full_path = pathspec.items[i].match;
 		pattern = NULL;
diff --git a/builtin/rm.c b/builtin/rm.c
index 5559a0b453..d89f241e97 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;
 
@@ -297,6 +298,8 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 	ensure_full_index(&the_index);
 	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);
@@ -310,24 +313,34 @@ 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)
@@ -407,5 +420,5 @@ 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/cache.h b/cache.h
index b785ffb383..1666c38edb 100644
--- a/cache.h
+++ b/cache.h
@@ -895,13 +895,14 @@ int match_stat_data_racy(const struct index_state *istate,
 
 void fill_stat_cache_info(struct index_state *istate, struct cache_entry *ce, struct stat *st);
 
-#define REFRESH_REALLY		0x0001	/* ignore_valid */
-#define REFRESH_UNMERGED	0x0002	/* allow unmerged */
-#define REFRESH_QUIET		0x0004	/* be quiet about it */
-#define REFRESH_IGNORE_MISSING	0x0008	/* ignore non-existent */
-#define REFRESH_IGNORE_SUBMODULES	0x0010	/* ignore submodules */
-#define REFRESH_IN_PORCELAIN	0x0020	/* user friendly output, not "needs update" */
-#define REFRESH_PROGRESS	0x0040  /* show progress bar if stderr is tty */
+#define REFRESH_REALLY                   (1 << 0) /* ignore_valid */
+#define REFRESH_UNMERGED                 (1 << 1) /* allow unmerged */
+#define REFRESH_QUIET                    (1 << 2) /* be quiet about it */
+#define REFRESH_IGNORE_MISSING           (1 << 3) /* ignore non-existent */
+#define REFRESH_IGNORE_SUBMODULES        (1 << 4) /* ignore submodules */
+#define REFRESH_IN_PORCELAIN             (1 << 5) /* user friendly output, not "needs update" */
+#define REFRESH_PROGRESS                 (1 << 6) /* show progress bar if stderr is tty */
+#define REFRESH_IGNORE_SKIP_WORKTREE     (1 << 7) /* ignore skip_worktree entries */
 int refresh_index(struct index_state *, unsigned int flags, const struct pathspec *pathspec, char *seen, const char *header_msg);
 /*
  * Refresh the index and write it to disk.
diff --git a/pathspec.c b/pathspec.c
index 14c7e9fbe3..08f8d3eedc 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -21,7 +21,8 @@
  */
 void add_pathspec_matches_against_index(const struct pathspec *pathspec,
 					struct index_state *istate,
-					char *seen)
+					char *seen,
+					enum ps_skip_worktree_action sw_action)
 {
 	int num_unmatched = 0, i;
 
@@ -40,6 +41,8 @@ void add_pathspec_matches_against_index(const struct pathspec *pathspec,
 	ensure_full_index(istate);
 	for (i = 0; i < istate->cache_nr; i++) {
 		const struct cache_entry *ce = istate->cache[i];
+		if (sw_action == PS_IGNORE_SKIP_WORKTREE && ce_skip_worktree(ce))
+			continue;
 		ce_path_match(istate, ce, pathspec, seen);
 	}
 }
@@ -53,10 +56,26 @@ void add_pathspec_matches_against_index(const struct pathspec *pathspec,
  * given pathspecs achieves against all items in the index.
  */
 char *find_pathspecs_matching_against_index(const struct pathspec *pathspec,
-					    struct index_state *istate)
+					    struct index_state *istate,
+					    enum ps_skip_worktree_action sw_action)
+{
+	char *seen = xcalloc(pathspec->nr, 1);
+	add_pathspec_matches_against_index(pathspec, istate, seen, sw_action);
+	return seen;
+}
+
+char *find_pathspecs_matching_skip_worktree(const struct pathspec *pathspec)
 {
+	struct index_state *istate = the_repository->index;
 	char *seen = xcalloc(pathspec->nr, 1);
-	add_pathspec_matches_against_index(pathspec, istate, seen);
+	int i;
+
+	for (i = 0; i < istate->cache_nr; i++) {
+		struct cache_entry *ce = istate->cache[i];
+		if (ce_skip_worktree(ce))
+		    ce_path_match(istate, ce, pathspec, seen);
+	}
+
 	return seen;
 }
 
diff --git a/pathspec.h b/pathspec.h
index 2ccc8080b6..fceebb876f 100644
--- a/pathspec.h
+++ b/pathspec.h
@@ -149,11 +149,25 @@ static inline int ps_strcmp(const struct pathspec_item *item,
 		return strcmp(s1, s2);
 }
 
+enum ps_skip_worktree_action {
+  PS_HEED_SKIP_WORKTREE = 0,
+  PS_IGNORE_SKIP_WORKTREE = 1
+};
 void add_pathspec_matches_against_index(const struct pathspec *pathspec,
 					struct index_state *istate,
-					char *seen);
+					char *seen,
+					enum ps_skip_worktree_action sw_action);
 char *find_pathspecs_matching_against_index(const struct pathspec *pathspec,
-					    struct index_state *istate);
+					    struct index_state *istate,
+					    enum ps_skip_worktree_action sw_action);
+char *find_pathspecs_matching_skip_worktree(const struct pathspec *pathspec);
+static inline int matches_skip_worktree(const struct pathspec *pathspec,
+					int item, char **seen_ptr)
+{
+	if (!*seen_ptr)
+		*seen_ptr = find_pathspecs_matching_skip_worktree(pathspec);
+	return (*seen_ptr)[item];
+}
 int match_pathspec_attrs(struct index_state *istate,
 			 const char *name, int namelen,
 			 const struct pathspec_item *item);
diff --git a/read-cache.c b/read-cache.c
index eb66fddb1b..aa0c6fe490 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1546,6 +1546,7 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 	int quiet = (flags & REFRESH_QUIET) != 0;
 	int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
 	int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
+	int ignore_skip_worktree = (flags & REFRESH_IGNORE_SKIP_WORKTREE) != 0;
 	int first = 1;
 	int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
 	unsigned int options = (CE_MATCH_REFRESH |
@@ -1590,6 +1591,8 @@ int refresh_index(struct index_state *istate, unsigned int flags,
 		ce = istate->cache[i];
 		if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
 			continue;
+		if (ignore_skip_worktree && ce_skip_worktree(ce))
+			continue;
 
 		if (pathspec && !ce_path_match(istate, ce, pathspec, seen))
 			filtered = 1;
diff --git a/t/t3602-rm-sparse-checkout.sh b/t/t3602-rm-sparse-checkout.sh
new file mode 100755
index 0000000000..e9e9a15c74
--- /dev/null
+++ b/t/t3602-rm-sparse-checkout.sh
@@ -0,0 +1,78 @@
+#!/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_error_header <<-EOF &&
+	The following pathspecs didn't match any eligible path, but they do match index
+	entries outside the current sparse checkout:
+	EOF
+
+	cat >sparse_hint <<-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
+
+	echo b | cat sparse_error_header - >sparse_entry_b_error &&
+	cat sparse_entry_b_error sparse_hint >b_error_and_hint
+"
+
+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_cmp 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_cmp 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 &&
+	grep "fatal: pathspec .nonexistent. did not match any files" stderr &&
+	! grep -F -f sparse_error_header 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/t3700-add.sh b/t/t3700-add.sh
index b3b122ff97..dd3011430d 100755
--- a/t/t3700-add.sh
+++ b/t/t3700-add.sh
@@ -196,6 +196,12 @@ test_expect_success 'git add --refresh with pathspec' '
 	grep baz actual
 '
 
+test_expect_success 'git add --refresh correctly reports no match error' "
+	echo \"fatal: pathspec ':(icase)nonexistent' did not match any files\" >expect &&
+	test_must_fail git add --refresh ':(icase)nonexistent' 2>actual &&
+	test_cmp expect actual
+"
+
 test_expect_success POSIXPERM,SANITY 'git add should fail atomically upon an unreadable file' '
 	git reset --hard &&
 	date >foo1 &&
diff --git a/t/t3705-add-sparse-checkout.sh b/t/t3705-add-sparse-checkout.sh
new file mode 100755
index 0000000000..2b1fd0d0ee
--- /dev/null
+++ b/t/t3705-add-sparse-checkout.sh
@@ -0,0 +1,155 @@
+#!/bin/sh
+
+test_description='git add in sparse checked out working trees'
+
+. ./test-lib.sh
+
+SPARSE_ENTRY_BLOB=""
+
+# Optionally take a printf format string to write to the sparse_entry file
+setup_sparse_entry () {
+	# 'sparse_entry' might already be in the index with the skip-worktree
+	# bit set. Remove it so that the subsequent git add can update it.
+	git update-index --force-remove sparse_entry &&
+	if test $# -eq 1
+	then
+		printf "$1" >sparse_entry
+	else
+		>sparse_entry
+	fi &&
+	git add sparse_entry &&
+	git update-index --skip-worktree sparse_entry &&
+	SPARSE_ENTRY_BLOB=$(git rev-parse :sparse_entry)
+}
+
+test_sparse_entry_unchanged () {
+	echo "100644 $SPARSE_ENTRY_BLOB 0	sparse_entry" >expected &&
+	git ls-files --stage sparse_entry >actual &&
+	test_cmp expected actual
+}
+
+setup_gitignore () {
+	test_when_finished rm -f .gitignore &&
+	cat >.gitignore <<-EOF
+	*
+	!/sparse_entry
+	EOF
+}
+
+test_expect_success 'setup' "
+	cat >sparse_error_header <<-EOF &&
+	The following pathspecs didn't match any eligible path, but they do match index
+	entries outside the current sparse checkout:
+	EOF
+
+	cat >sparse_hint <<-EOF &&
+	hint: Disable or modify the sparsity rules if you intend to update such entries.
+	hint: Disable this message with \"git config advice.updateSparsePath false\"
+	EOF
+
+	echo sparse_entry | cat sparse_error_header - >sparse_entry_error &&
+	cat sparse_entry_error sparse_hint >error_and_hint
+"
+
+test_expect_success 'git add does not remove sparse entries' '
+	setup_sparse_entry &&
+	rm sparse_entry &&
+	test_must_fail git add sparse_entry 2>stderr &&
+	test_cmp error_and_hint stderr &&
+	test_sparse_entry_unchanged
+'
+
+test_expect_success 'git add -A does not remove sparse entries' '
+	setup_sparse_entry &&
+	rm sparse_entry &&
+	setup_gitignore &&
+	git add -A 2>stderr &&
+	test_must_be_empty stderr &&
+	test_sparse_entry_unchanged
+'
+
+test_expect_success 'git add . does not remove sparse entries' '
+	setup_sparse_entry &&
+	rm sparse_entry &&
+	setup_gitignore &&
+	test_must_fail git add . 2>stderr &&
+
+	cat sparse_error_header >expect &&
+	echo . >>expect &&
+	cat sparse_hint >>expect &&
+
+	test_cmp expect stderr &&
+	test_sparse_entry_unchanged
+'
+
+for opt in "" -f -u --ignore-removal --dry-run
+do
+	test_expect_success "git add${opt:+ $opt} does not update sparse entries" '
+		setup_sparse_entry &&
+		echo modified >sparse_entry &&
+		test_must_fail git add $opt sparse_entry 2>stderr &&
+		test_cmp error_and_hint stderr &&
+		test_sparse_entry_unchanged
+	'
+done
+
+test_expect_success 'git add --refresh does not update sparse entries' '
+	setup_sparse_entry &&
+	git ls-files --debug sparse_entry | grep mtime >before &&
+	test-tool chmtime -60 sparse_entry &&
+	test_must_fail git add --refresh sparse_entry 2>stderr &&
+	test_cmp error_and_hint stderr &&
+	git ls-files --debug sparse_entry | grep mtime >after &&
+	test_cmp before after
+'
+
+test_expect_success 'git add --chmod does not update sparse entries' '
+	setup_sparse_entry &&
+	test_must_fail git add --chmod=+x sparse_entry 2>stderr &&
+	test_cmp error_and_hint stderr &&
+	test_sparse_entry_unchanged &&
+	! test -x sparse_entry
+'
+
+test_expect_success 'git add --renormalize does not update sparse entries' '
+	test_config core.autocrlf false &&
+	setup_sparse_entry "LINEONE\r\nLINETWO\r\n" &&
+	echo "sparse_entry text=auto" >.gitattributes &&
+	test_must_fail git add --renormalize sparse_entry 2>stderr &&
+	test_cmp error_and_hint stderr &&
+	test_sparse_entry_unchanged
+'
+
+test_expect_success 'git add --dry-run --ignore-missing warn on sparse path' '
+	setup_sparse_entry &&
+	rm sparse_entry &&
+	test_must_fail git add --dry-run --ignore-missing sparse_entry 2>stderr &&
+	test_cmp error_and_hint stderr &&
+	test_sparse_entry_unchanged
+'
+
+test_expect_success 'do not advice about sparse entries when they do not match the pathspec' '
+	setup_sparse_entry &&
+	test_must_fail git add nonexistent 2>stderr &&
+	grep "fatal: pathspec .nonexistent. did not match any files" stderr &&
+	! grep -F -f sparse_error_header stderr
+'
+
+test_expect_success 'do not warn when pathspec matches dense entries' '
+	setup_sparse_entry &&
+	echo modified >sparse_entry &&
+	>dense_entry &&
+	git add "*_entry" 2>stderr &&
+	test_must_be_empty stderr &&
+	test_sparse_entry_unchanged &&
+	git ls-files --error-unmatch dense_entry
+'
+
+test_expect_success 'add obeys advice.updateSparsePath' '
+	setup_sparse_entry &&
+	test_must_fail git -c advice.updateSparsePath=false add sparse_entry 2>stderr &&
+	test_cmp sparse_entry_error stderr
+
+'
+
+test_done
diff --git a/t/t7011-skip-worktree-reading.sh b/t/t7011-skip-worktree-reading.sh
index 26852586ac..1761a2b1b9 100755
--- a/t/t7011-skip-worktree-reading.sh
+++ b/t/t7011-skip-worktree-reading.sh
@@ -132,11 +132,6 @@ 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 &&
diff --git a/t/t7012-skip-worktree-writing.sh b/t/t7012-skip-worktree-writing.sh
index f2a8e76511..a1080b94e3 100755
--- a/t/t7012-skip-worktree-writing.sh
+++ b/t/t7012-skip-worktree-writing.sh
@@ -60,13 +60,6 @@ setup_absent() {
 	git update-index --skip-worktree 1
 }
 
-test_absent() {
-	echo "100644 $EMPTY_BLOB 0	1" > expected &&
-	git ls-files --stage 1 > result &&
-	test_cmp expected result &&
-	test ! -f 1
-}
-
 setup_dirty() {
 	git update-index --force-remove 1 &&
 	echo dirty > 1 &&
@@ -100,18 +93,6 @@ test_expect_success 'index setup' '
 	test_cmp expected result
 '
 
-test_expect_success 'git-add ignores worktree content' '
-	setup_absent &&
-	git add 1 &&
-	test_absent
-'
-
-test_expect_success 'git-add ignores worktree content' '
-	setup_dirty &&
-	git add 1 &&
-	test_dirty
-'
-
 test_expect_success 'git-rm fails if worktree is dirty' '
 	setup_dirty &&
 	test_must_fail git rm 1 &&