Merge branch 'nd/sparse'

* nd/sparse: (25 commits)
  t7002: test for not using external grep on skip-worktree paths
  t7002: set test prerequisite "external-grep" if supported
  grep: do not do external grep on skip-worktree entries
  commit: correctly respect skip-worktree bit
  ie_match_stat(): do not ignore skip-worktree bit with CE_MATCH_IGNORE_VALID
  tests: rename duplicate t1009
  sparse checkout: inhibit empty worktree
  Add tests for sparse checkout
  read-tree: add --no-sparse-checkout to disable sparse checkout support
  unpack-trees(): ignore worktree check outside checkout area
  unpack_trees(): apply $GIT_DIR/info/sparse-checkout to the final index
  unpack-trees(): "enable" sparse checkout and load $GIT_DIR/info/sparse-checkout
  unpack-trees.c: generalize verify_* functions
  unpack-trees(): add CE_WT_REMOVE to remove on worktree alone
  Introduce "sparse checkout"
  dir.c: export excluded_1() and add_excludes_from_file_1()
  excluded_1(): support exclude files in index
  unpack-trees(): carry skip-worktree bit over in merged_entry()
  Read .gitignore from index if it is skip-worktree
  Avoid writing to buffer in add_excludes_from_file_1()
  ...

Conflicts:
	.gitignore
	Documentation/config.txt
	Documentation/git-update-index.txt
	Makefile
	entry.c
	t/t7002-grep.sh

1 files changed, 19 insertions, 2 deletions

diff --git a/builtin-grep.c b/builtin-grep.c
index af6c6fe8a7..529461fb8f 100644
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -220,6 +220,7 @@ static int exec_grep(int argc, const char **argv)
 	int status;
 
 	argv[argc] = NULL;
+	trace_argv_printf(argv, "trace: grep:");
 	pid = fork();
 	if (pid < 0)
 		return pid;
@@ -345,6 +346,21 @@ static void grep_add_color(struct strbuf *sb, const char *escape_seq)
 		strbuf_setlen(sb, sb->len - 1);
 }
 
+static int has_skip_worktree_entry(struct grep_opt *opt, const char **paths)
+{
+	int nr;
+	for (nr = 0; nr < active_nr; nr++) {
+		struct cache_entry *ce = active_cache[nr];
+		if (!S_ISREG(ce->ce_mode))
+			continue;
+		if (!pathspec_matches(paths, ce->name, opt->max_depth))
+			continue;
+		if (ce_skip_worktree(ce))
+			return 1;
+	}
+	return 0;
+}
+
 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 {
 	int i, nr, argc, hit, len, status;
@@ -353,7 +369,8 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 	char *argptr = randarg;
 	struct grep_pat *p;
 
-	if (opt->extended || (opt->relative && opt->prefix_length))
+	if (opt->extended || (opt->relative && opt->prefix_length)
+	    || has_skip_worktree_entry(opt, paths))
 		return -1;
 	len = nr = 0;
 	push_arg("grep");
@@ -510,7 +527,7 @@ static int grep_cache(struct grep_opt *opt, const char **paths, int cached,
 		 * are identical, even if worktree file has been modified, so use
 		 * cache version instead
 		 */
-		if (cached || (ce->ce_flags & CE_VALID)) {
+		if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
 			if (ce_stage(ce))
 				continue;
 			hit |= grep_sha1(opt, ce->sha1, ce->name, 0);