Merge branch 'jl/submodule-ignore-diff'

* jl/submodule-ignore-diff:
  Add tests for the diff.ignoreSubmodules config option
  Add the 'diff.ignoreSubmodules' config setting
  Submodules: Use "ignore" settings from .gitmodules too for diff and status
  Submodules: Add the new "ignore" config option for diff and status

Conflicts:
	diff.c

Documentation/config.txt

@@ -826,6 +826,11 @@ diff.renames::
 	will enable basic rename detection.  If set to "copies" or
 	"copy", it will detect copies, as well.
 
+diff.ignoreSubmodules::
+	Sets the default value of --ignore-submodules. Note that this
+	affects only 'git diff' Porcelain, and not lower level 'diff'
+	commands such as 'git diff-files'.
+
 diff.suppressBlankEmpty::
 	A boolean to inhibit the standard behavior of printing a space
 	before each empty output line. Defaults to false.
@@ -1749,6 +1754,19 @@ submodule.<name>.update::
 	URL and other values found in the `.gitmodules` file.  See
 	linkgit:git-submodule[1] and linkgit:gitmodules[5] for details.
 
+submodule.<name>.ignore::
+	Defines under what circumstances "git status" and the diff family show
+	a submodule as modified. When set to "all", it will never be considered
+	modified, "dirty" will ignore all changes to the submodules work tree and
+	takes only differences between the HEAD of the submodule and the commit
+	recorded in the superproject into account. "untracked" will additionally
+	let submodules with modified tracked files in their work tree show up.
+	Using "none" (the default when this option is not set) also shows
+	submodules that have untracked files in their work tree as changed.
+	This setting overrides any setting made in .gitmodules for this submodule,
+	both settings can be overriden on the command line by using the
+	"--ignore-submodules" option.
+
 tar.umask::
 	This variable can be used to restrict the permission bits of
 	tar archive entries.  The default is 0002, which turns off the

Documentation/diff-options.txt

@@ -355,7 +355,11 @@ endif::git-format-patch[]
 
 --ignore-submodules[=<when>]::
 	Ignore changes to submodules in the diff generation. <when> can be
-	either "untracked", "dirty" or "all", which is the default. When
+	either "none", "untracked", "dirty" or "all", which is the default
+	Using "none" will consider the submodule modified when it either contains
+	untracked or modified files or its HEAD differs from the commit recorded
+	in the superproject and can be used to override any settings of the
+	'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 	"untracked" is used submodules are not considered dirty when they only
 	contain untracked content (but they are still scanned for modified
 	content). Using "dirty" ignores all changes to the work tree of submodules,

Documentation/git-status.txt

@@ -55,7 +55,11 @@ specified.
 
 --ignore-submodules[=<when>]::
 	Ignore changes to submodules when looking for changes. <when> can be
-	either "untracked", "dirty" or "all", which is the default. When
+	either "none", "untracked", "dirty" or "all", which is the default.
+	Using "none" will consider the submodule modified when it either contains
+	untracked or modified files or its HEAD differs from the commit recorded
+	in the superproject and can be used to override any settings of the
+	'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 	"untracked" is used submodules are not considered dirty when they only
 	contain untracked content (but they are still scanned for modified
 	content). Using "dirty" ignores all changes to the work tree of submodules,

Documentation/gitmodules.txt

@@ -44,6 +44,21 @@ submodule.<name>.update::
 	This config option is overridden if 'git submodule update' is given
 	the '--merge' or '--rebase' options.
 
+submodule.<name>.ignore::
+	Defines under what circumstances "git status" and the diff family show
+	a submodule as modified. When set to "all", it will never be considered
+	modified, "dirty" will ignore all changes to the submodules work tree and
+	takes only differences between the HEAD of the submodule and the commit
+	recorded in the superproject into account. "untracked" will additionally
+	let submodules with modified tracked files in their work tree show up.
+	Using "none" (the default when this option is not set) also shows
+	submodules that have untracked files in their work tree as changed.
+	If this option is also present in the submodules entry in .git/config of
+	the superproject, the setting there will override the one found in
+	.gitmodules.
+	Both settings can be overriden on the command line by using the
+	"--ignore-submodule" option.
+
 
 EXAMPLES
 --------

builtin/commit.c

@@ -25,6 +25,7 @@
 #include "rerere.h"
 #include "unpack-trees.h"
 #include "quote.h"
+#include "submodule.h"
 
 static const char * const builtin_commit_usage[] = {
 	"git commit [options] [--] <filepattern>...",
@@ -1073,6 +1074,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 		status_format = STATUS_FORMAT_PORCELAIN;
 
 	wt_status_prepare(&s);
+	gitmodules_config();
 	git_config(git_status_config, &s);
 	in_merge = file_exists(git_path("MERGE_HEAD"));
 	argc = parse_options(argc, argv, prefix,

builtin/diff-files.c

@@ -8,6 +8,7 @@
 #include "commit.h"
 #include "revision.h"
 #include "builtin.h"
+#include "submodule.h"
 
 static const char diff_files_usage[] =
 "git diff-files [-q] [-0/-1/2/3 |-c|--cc] [<common diff options>] [<path>...]"
@@ -20,6 +21,7 @@ int cmd_diff_files(int argc, const char **argv, const char *prefix)
 	unsigned options = 0;
 
 	init_revisions(&rev, prefix);
+	gitmodules_config();
 	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
 	rev.abbrev = 0;
 

builtin/diff-index.c

@@ -3,6 +3,7 @@
 #include "commit.h"
 #include "revision.h"
 #include "builtin.h"
+#include "submodule.h"
 
 static const char diff_cache_usage[] =
 "git diff-index [-m] [--cached] "
@@ -17,6 +18,7 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
 	int result;
 
 	init_revisions(&rev, prefix);
+	gitmodules_config();
 	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
 	rev.abbrev = 0;
 

builtin/diff-tree.c

@@ -3,6 +3,7 @@
 #include "commit.h"
 #include "log-tree.h"
 #include "builtin.h"
+#include "submodule.h"
 
 static struct rev_info log_tree_opt;
 
@@ -112,6 +113,7 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
 	int read_stdin = 0;
 
 	init_revisions(opt, prefix);
+	gitmodules_config();
 	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
 	opt->abbrev = 0;
 	opt->diff = 1;

builtin/diff.c

@@ -13,6 +13,7 @@
 #include "revision.h"
 #include "log-tree.h"
 #include "builtin.h"
+#include "submodule.h"
 
 struct blobinfo {
 	unsigned char sha1[20];
@@ -279,6 +280,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 	 */
 
 	prefix = setup_git_directory_gently(&nongit);
+	gitmodules_config();
 	git_config(git_diff_ui_config, NULL);
 
 	if (diff_use_color_default == -1)

diff-lib.c

@@ -68,11 +68,16 @@ static int match_stat_with_submodule(struct diff_options *diffopt,
 				      unsigned ce_option, unsigned *dirty_submodule)
 {
 	int changed = ce_match_stat(ce, st, ce_option);
-	if (S_ISGITLINK(ce->ce_mode)
-	    && !DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES)
-	    && !DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
-	    && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES))) {
-		*dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
+	if (S_ISGITLINK(ce->ce_mode)) {
+		unsigned orig_flags = diffopt->flags;
+		if (!DIFF_OPT_TST(diffopt, OVERRIDE_SUBMODULE_CONFIG))
+			set_diffopt_flags_from_submodule_config(diffopt, ce->name);
+		if (DIFF_OPT_TST(diffopt, IGNORE_SUBMODULES))
+			changed = 0;
+		else if (!DIFF_OPT_TST(diffopt, IGNORE_DIRTY_SUBMODULES)
+		    && (!changed || DIFF_OPT_TST(diffopt, DIRTY_SUBMODULES)))
+			*dirty_submodule = is_submodule_modified(ce->name, DIFF_OPT_TST(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES));
+		diffopt->flags = orig_flags;
 	}
 	return changed;
 }

diff.c

@@ -31,6 +31,7 @@ static const char *external_diff_cmd_cfg;
 int diff_auto_refresh_index = 1;
 static int diff_mnemonic_prefix;
 static int diff_no_prefix;
+static struct diff_options default_diff_options;
 
 static char diff_colors[][COLOR_MAXLEN] = {
 	GIT_COLOR_RESET,
@@ -107,6 +108,9 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
 	if (!strcmp(var, "diff.wordregex"))
 		return git_config_string(&diff_word_regex_cfg, var, value);
 
+	if (!strcmp(var, "diff.ignoresubmodules"))
+		handle_ignore_submodules_arg(&default_diff_options, value);
+
 	return git_diff_basic_config(var, value, cb);
 }
 
@@ -141,6 +145,9 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
 		return 0;
 	}
 
+	if (!prefixcmp(var, "submodule."))
+		return parse_submodule_config_option(var, value);
+
 	return git_color_default_config(var, value, cb);
 }
 
@@ -2819,7 +2826,7 @@ static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
 
 void diff_setup(struct diff_options *options)
 {
-	memset(options, 0, sizeof(*options));
+	memcpy(options, &default_diff_options, sizeof(*options));
 
 	options->file = stdout;
 
@@ -3171,11 +3178,13 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		DIFF_OPT_SET(options, ALLOW_TEXTCONV);
 	else if (!strcmp(arg, "--no-textconv"))
 		DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
-	else if (!strcmp(arg, "--ignore-submodules"))
+	else if (!strcmp(arg, "--ignore-submodules")) {
+		DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
 		handle_ignore_submodules_arg(options, "all");
-	else if (!prefixcmp(arg, "--ignore-submodules="))
+	} else if (!prefixcmp(arg, "--ignore-submodules=")) {
+		DIFF_OPT_SET(options, OVERRIDE_SUBMODULE_CONFIG);
 		handle_ignore_submodules_arg(options, arg + 20);
-	else if (!strcmp(arg, "--submodule"))
+	} else if (!strcmp(arg, "--submodule"))
 		DIFF_OPT_SET(options, SUBMODULE_LOG);
 	else if (!prefixcmp(arg, "--submodule=")) {
 		if (!strcmp(arg + 12, "log"))
@@ -4108,14 +4117,32 @@ int diff_result_code(struct diff_options *opt, int status)
 	return result;
 }
 
+/*
+ * Shall changes to this submodule be ignored?
+ *
+ * Submodule changes can be configured to be ignored separately for each path,
+ * but that configuration can be overridden from the command line.
+ */
+static int is_submodule_ignored(const char *path, struct diff_options *options)
+{
+	int ignored = 0;
+	unsigned orig_flags = options->flags;
+	if (!DIFF_OPT_TST(options, OVERRIDE_SUBMODULE_CONFIG))
+		set_diffopt_flags_from_submodule_config(options, path);
+	if (DIFF_OPT_TST(options, IGNORE_SUBMODULES))
+		ignored = 1;
+	options->flags = orig_flags;
+	return ignored;
+}
+
 void diff_addremove(struct diff_options *options,
 		    int addremove, unsigned mode,
 		    const unsigned char *sha1,
 		    const char *concatpath, unsigned dirty_submodule)
 {
 	struct diff_filespec *one, *two;
 
-	if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(mode))
+	if (S_ISGITLINK(mode) && is_submodule_ignored(concatpath, options))
 		return;
 
 	/* This may look odd, but it is a preparation for
@@ -4162,8 +4189,8 @@ void diff_change(struct diff_options *options,
 {
 	struct diff_filespec *one, *two;
 
-	if (DIFF_OPT_TST(options, IGNORE_SUBMODULES) && S_ISGITLINK(old_mode)
-			&& S_ISGITLINK(new_mode))
+	if (S_ISGITLINK(old_mode) && S_ISGITLINK(new_mode) &&
+	    is_submodule_ignored(concatpath, options))
 		return;
 
 	if (DIFF_OPT_TST(options, REVERSE_DIFF)) {

diff.h

@@ -77,6 +77,7 @@ typedef struct strbuf *(*diff_prefix_fn_t)(struct diff_options *opt, void *data)
 #define DIFF_OPT_DIRTY_SUBMODULES    (1 << 24)
 #define DIFF_OPT_IGNORE_UNTRACKED_IN_SUBMODULES (1 << 25)
 #define DIFF_OPT_IGNORE_DIRTY_SUBMODULES (1 << 26)
+#define DIFF_OPT_OVERRIDE_SUBMODULE_CONFIG (1 << 27)
 
 #define DIFF_OPT_TST(opts, flag)    ((opts)->flags & DIFF_OPT_##flag)
 #define DIFF_OPT_SET(opts, flag)    ((opts)->flags |= DIFF_OPT_##flag)

submodule.c

@@ -6,6 +6,10 @@
 #include "revision.h"
 #include "run-command.h"
 #include "diffcore.h"
+#include "string-list.h"
+
+struct string_list config_name_for_path;
+struct string_list config_ignore_for_name;
 
 static int add_submodule_odb(const char *path)
 {
@@ -46,16 +50,90 @@ static int add_submodule_odb(const char *path)
 	return ret;
 }
 
+void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
+					     const char *path)
+{
+	struct string_list_item *path_option, *ignore_option;
+	path_option = unsorted_string_list_lookup(&config_name_for_path, path);
+	if (path_option) {
+		ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
+		if (ignore_option)
+			handle_ignore_submodules_arg(diffopt, ignore_option->util);
+	}
+}
+
+static int submodule_config(const char *var, const char *value, void *cb)
+{
+	if (!prefixcmp(var, "submodule."))
+		return parse_submodule_config_option(var, value);
+	return 0;
+}
+
+void gitmodules_config(void)
+{
+	const char *work_tree = get_git_work_tree();
+	if (work_tree) {
+		struct strbuf gitmodules_path = STRBUF_INIT;
+		strbuf_addstr(&gitmodules_path, work_tree);
+		strbuf_addstr(&gitmodules_path, "/.gitmodules");
+		git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
+		strbuf_release(&gitmodules_path);
+	}
+}
+
+int parse_submodule_config_option(const char *var, const char *value)
+{
+	int len;
+	struct string_list_item *config;
+	struct strbuf submodname = STRBUF_INIT;
+
+	var += 10;		/* Skip "submodule." */
+
+	len = strlen(var);
+	if ((len > 5) && !strcmp(var + len - 5, ".path")) {
+		strbuf_add(&submodname, var, len - 5);
+		config = unsorted_string_list_lookup(&config_name_for_path, value);
+		if (config)
+			free(config->util);
+		else
+			config = string_list_append(&config_name_for_path, xstrdup(value));
+		config->util = strbuf_detach(&submodname, NULL);
+		strbuf_release(&submodname);
+	} else if ((len > 7) && !strcmp(var + len - 7, ".ignore")) {
+		if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
+		    strcmp(value, "all") && strcmp(value, "none")) {
+			warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
+			return 0;
+		}
+
+		strbuf_add(&submodname, var, len - 7);
+		config = unsorted_string_list_lookup(&config_ignore_for_name, submodname.buf);
+		if (config)
+			free(config->util);
+		else
+			config = string_list_append(&config_ignore_for_name,
+						    strbuf_detach(&submodname, NULL));
+		strbuf_release(&submodname);
+		config->util = xstrdup(value);
+		return 0;
+	}
+	return 0;
+}
+
 void handle_ignore_submodules_arg(struct diff_options *diffopt,
 				  const char *arg)
 {
+	DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
+	DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
+	DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
+
 	if (!strcmp(arg, "all"))
 		DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 	else if (!strcmp(arg, "untracked"))
 		DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 	else if (!strcmp(arg, "dirty"))
 		DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
-	else
+	else if (strcmp(arg, "none"))
 		die("bad --ignore-submodules argument: %s", arg);
 }