submodule: check for unstaged .gitmodules outside of config parsing

Teach 'is_staging_gitmodules_ok()' to be able to determine in the
'.gitmodules' file has unstaged changes based on the passed in index
instead of relying on a global variable which is set during the
submodule-config parsing.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/mv.c

@@ -81,7 +81,7 @@ static void prepare_move_submodule(const char *src, int first,
 	struct strbuf submodule_dotgit = STRBUF_INIT;
 	if (!S_ISGITLINK(active_cache[first]->ce_mode))
 		die(_("Directory %s is in index and no submodule?"), src);
-	if (!is_staging_gitmodules_ok())
+	if (!is_staging_gitmodules_ok(&the_index))
 		die(_("Please stage your changes to .gitmodules or stash them to proceed"));
 	strbuf_addf(&submodule_dotgit, "%s/.git", src);
 	*submodule_gitfile = read_gitfile(submodule_dotgit.buf);

builtin/rm.c

@@ -286,7 +286,7 @@ int cmd_rm(int argc, const char **argv, const char *prefix)
 		list.entry[list.nr].name = xstrdup(ce->name);
 		list.entry[list.nr].is_submodule = S_ISGITLINK(ce->ce_mode);
 		if (list.entry[list.nr++].is_submodule &&
-		    !is_staging_gitmodules_ok())
+		    !is_staging_gitmodules_ok(&the_index))
 			die (_("Please stage your changes to .gitmodules or stash them to proceed"));
 	}
 

submodule.c

@@ -37,18 +37,25 @@ static struct oid_array ref_tips_after_fetch;
 static int gitmodules_is_unmerged;
 
 /*
- * This flag is set if the .gitmodules file had unstaged modifications on
- * startup. This must be checked before allowing modifications to the
- * .gitmodules file with the intention to stage them later, because when
- * continuing we would stage the modifications the user didn't stage herself
- * too. That might change in a future version when we learn to stage the
- * changes we do ourselves without staging any previous modifications.
+ * Check if the .gitmodules file has unstaged modifications.  This must be
+ * checked before allowing modifications to the .gitmodules file with the
+ * intention to stage them later, because when continuing we would stage the
+ * modifications the user didn't stage herself too. That might change in a
+ * future version when we learn to stage the changes we do ourselves without
+ * staging any previous modifications.
  */
-static int gitmodules_is_modified;
-
-int is_staging_gitmodules_ok(void)
+int is_staging_gitmodules_ok(const struct index_state *istate)
 {
-	return !gitmodules_is_modified;
+	int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
+
+	if ((pos >= 0) && (pos < istate->cache_nr)) {
+		struct stat st;
+		if (lstat(GITMODULES_FILE, &st) == 0 &&
+		    ce_match_stat(istate->cache[pos], &st, 0) & DATA_CHANGED)
+			return 0;
+	}
+
+	return 1;
 }
 
 /*
@@ -231,11 +238,6 @@ void gitmodules_config(void)
 				    !memcmp(ce->name, GITMODULES_FILE, 11))
 					gitmodules_is_unmerged = 1;
 			}
-		} else if (pos < active_nr) {
-			struct stat st;
-			if (lstat(GITMODULES_FILE, &st) == 0 &&
-			    ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
-				gitmodules_is_modified = 1;
 		}
 
 		if (!gitmodules_is_unmerged)

submodule.h

@@ -33,7 +33,7 @@ struct submodule_update_strategy {
 };
 #define SUBMODULE_UPDATE_STRATEGY_INIT {SM_UPDATE_UNSPECIFIED, NULL}
 
-extern int is_staging_gitmodules_ok(void);
+extern int is_staging_gitmodules_ok(const struct index_state *istate);
 extern int update_path_in_gitmodules(const char *oldpath, const char *newpath);
 extern int remove_path_from_gitmodules(const char *path);
 extern void stage_updated_gitmodules(void);