Merge branch 'jx/clean-interactive'

Add "interactive" mode to "git clean".

The early part to refactor relative path related helper functions
looked sensible.

* jx/clean-interactive:
  test: run testcases with POSIX absolute paths on Windows
  test: add t7301 for git-clean--interactive
  git-clean: add documentation for interactive git-clean
  git-clean: add ask each interactive action
  git-clean: add select by numbers interactive action
  git-clean: add filter by pattern interactive action
  git-clean: use a git-add-interactive compatible UI
  git-clean: add colors to interactive git-clean
  git-clean: show items of del_list in columns
  git-clean: add support for -i/--interactive
  git-clean: refactor git-clean into two phases
  write_name{_quoted_relative,}(): remove redundant parameters
  quote_path_relative(): remove redundant parameter
  quote.c: substitute path_relative with relative_path
  path.c: refactor relative_path(), not only strip prefix
  test: add test cases for relative_path

1 files changed, 747 insertions, 31 deletions

diff --git a/builtin/clean.c b/builtin/clean.c
index e344137ef2..dba8387747 100644
--- a/builtin/clean.c
+++ b/builtin/clean.c
@@ -13,11 +13,16 @@
 #include "refs.h"
 #include "string-list.h"
 #include "quote.h"
+#include "column.h"
+#include "color.h"
 
 static int force = -1; /* unset */
+static int interactive;
+static struct string_list del_list = STRING_LIST_INIT_DUP;
+static unsigned int colopts;
 
 static const char *const builtin_clean_usage[] = {
-	N_("git clean [-d] [-f] [-n] [-q] [-e <pattern>] [-x | -X] [--] <paths>..."),
+	N_("git clean [-d] [-f] [-i] [-n] [-q] [-e <pattern>] [-x | -X] [--] <paths>..."),
 	NULL
 };
 
@@ -27,11 +32,112 @@ static const char *msg_skip_git_dir = N_("Skipping repository %s\n");
 static const char *msg_would_skip_git_dir = N_("Would skip repository %s\n");
 static const char *msg_warn_remove_failed = N_("failed to remove %s");
 
+static int clean_use_color = -1;
+static char clean_colors[][COLOR_MAXLEN] = {
+	GIT_COLOR_RESET,
+	GIT_COLOR_NORMAL,	/* PLAIN */
+	GIT_COLOR_BOLD_BLUE,	/* PROMPT */
+	GIT_COLOR_BOLD,		/* HEADER */
+	GIT_COLOR_BOLD_RED,	/* HELP */
+	GIT_COLOR_BOLD_RED,	/* ERROR */
+};
+enum color_clean {
+	CLEAN_COLOR_RESET = 0,
+	CLEAN_COLOR_PLAIN = 1,
+	CLEAN_COLOR_PROMPT = 2,
+	CLEAN_COLOR_HEADER = 3,
+	CLEAN_COLOR_HELP = 4,
+	CLEAN_COLOR_ERROR = 5,
+};
+
+#define MENU_OPTS_SINGLETON		01
+#define MENU_OPTS_IMMEDIATE		02
+#define MENU_OPTS_LIST_ONLY		04
+
+struct menu_opts {
+	const char *header;
+	const char *prompt;
+	int flags;
+};
+
+#define MENU_RETURN_NO_LOOP		10
+
+struct menu_item {
+	char hotkey;
+	const char *title;
+	int selected;
+	int (*fn)();
+};
+
+enum menu_stuff_type {
+	MENU_STUFF_TYPE_STRING_LIST = 1,
+	MENU_STUFF_TYPE_MENU_ITEM
+};
+
+struct menu_stuff {
+	enum menu_stuff_type type;
+	int nr;
+	void *stuff;
+};
+
+static int parse_clean_color_slot(const char *var)
+{
+	if (!strcasecmp(var, "reset"))
+		return CLEAN_COLOR_RESET;
+	if (!strcasecmp(var, "plain"))
+		return CLEAN_COLOR_PLAIN;
+	if (!strcasecmp(var, "prompt"))
+		return CLEAN_COLOR_PROMPT;
+	if (!strcasecmp(var, "header"))
+		return CLEAN_COLOR_HEADER;
+	if (!strcasecmp(var, "help"))
+		return CLEAN_COLOR_HELP;
+	if (!strcasecmp(var, "error"))
+		return CLEAN_COLOR_ERROR;
+	return -1;
+}
+
 static int git_clean_config(const char *var, const char *value, void *cb)
 {
-	if (!strcmp(var, "clean.requireforce"))
+	if (!prefixcmp(var, "column."))
+		return git_column_config(var, value, "clean", &colopts);
+
+	/* honors the color.interactive* config variables which also
+	   applied in git-add--interactive and git-stash */
+	if (!strcmp(var, "color.interactive")) {
+		clean_use_color = git_config_colorbool(var, value);
+		return 0;
+	}
+	if (!prefixcmp(var, "color.interactive.")) {
+		int slot = parse_clean_color_slot(var +
+						  strlen("color.interactive."));
+		if (slot < 0)
+			return 0;
+		if (!value)
+			return config_error_nonbool(var);
+		color_parse(value, var, clean_colors[slot]);
+		return 0;
+	}
+
+	if (!strcmp(var, "clean.requireforce")) {
 		force = !git_config_bool(var, value);
-	return git_default_config(var, value, cb);
+		return 0;
+	}
+
+	/* inspect the color.ui config variable and others */
+	return git_color_default_config(var, value, cb);
+}
+
+static const char *clean_get_color(enum color_clean ix)
+{
+	if (want_color(clean_use_color))
+		return clean_colors[ix];
+	return "";
+}
+
+static void clean_print_color(enum color_clean ix)
+{
+	printf("%s", clean_get_color(ix));
 }
 
 static int exclude_cb(const struct option *opt, const char *arg, int unset)
@@ -56,7 +162,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 	if ((force_flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
 			!resolve_gitlink_ref(path->buf, "HEAD", submodule_head)) {
 		if (!quiet) {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			printf(dry_run ?  _(msg_would_skip_git_dir) : _(msg_skip_git_dir),
 					quoted.buf);
 		}
@@ -70,7 +176,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		/* an empty dir could be removed even if it is unreadble */
 		res = dry_run ? 0 : rmdir(path->buf);
 		if (res) {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			warning(_(msg_warn_remove_failed), quoted.buf);
 			*dir_gone = 0;
 		}
@@ -94,7 +200,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 			if (remove_dirs(path, prefix, force_flag, dry_run, quiet, &gone))
 				ret = 1;
 			if (gone) {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				string_list_append(&dels, quoted.buf);
 			} else
 				*dir_gone = 0;
@@ -102,10 +208,10 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		} else {
 			res = dry_run ? 0 : unlink(path->buf);
 			if (!res) {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				string_list_append(&dels, quoted.buf);
 			} else {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				warning(_(msg_warn_remove_failed), quoted.buf);
 				*dir_gone = 0;
 				ret = 1;
@@ -127,7 +233,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		if (!res)
 			*dir_gone = 1;
 		else {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			warning(_(msg_warn_remove_failed), quoted.buf);
 			*dir_gone = 0;
 			ret = 1;
@@ -142,24 +248,609 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 	return ret;
 }
 
+static void pretty_print_dels(void)
+{
+	struct string_list list = STRING_LIST_INIT_DUP;
+	struct string_list_item *item;
+	struct strbuf buf = STRBUF_INIT;
+	const char *qname;
+	struct column_options copts;
+
+	for_each_string_list_item(item, &del_list) {
+		qname = quote_path_relative(item->string, NULL, &buf);
+		string_list_append(&list, qname);
+	}
+
+	/*
+	 * always enable column display, we only consult column.*
+	 * about layout strategy and stuff
+	 */
+	colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
+	memset(&copts, 0, sizeof(copts));
+	copts.indent = "  ";
+	copts.padding = 2;
+	print_columns(&list, colopts, &copts);
+	strbuf_release(&buf);
+	string_list_clear(&list, 0);
+}
+
+static void pretty_print_menus(struct string_list *menu_list)
+{
+	unsigned int local_colopts = 0;
+	struct column_options copts;
+
+	local_colopts = COL_ENABLED | COL_ROW;
+	memset(&copts, 0, sizeof(copts));
+	copts.indent = "  ";
+	copts.padding = 2;
+	print_columns(menu_list, local_colopts, &copts);
+}
+
+static void prompt_help_cmd(int singleton)
+{
+	clean_print_color(CLEAN_COLOR_HELP);
+	printf_ln(singleton ?
+		  _("Prompt help:\n"
+		    "1          - select a numbered item\n"
+		    "foo        - select item based on unique prefix\n"
+		    "           - (empty) select nothing") :
+		  _("Prompt help:\n"
+		    "1          - select a single item\n"
+		    "3-5        - select a range of items\n"
+		    "2-3,6-9    - select multiple ranges\n"
+		    "foo        - select item based on unique prefix\n"
+		    "-...       - unselect specified items\n"
+		    "*          - choose all items\n"
+		    "           - (empty) finish selecting"));
+	clean_print_color(CLEAN_COLOR_RESET);
+}
+
+/*
+ * display menu stuff with number prefix and hotkey highlight
+ */
+static void print_highlight_menu_stuff(struct menu_stuff *stuff, int **chosen)
+{
+	struct string_list menu_list = STRING_LIST_INIT_DUP;
+	struct strbuf menu = STRBUF_INIT;
+	struct strbuf buf = STRBUF_INIT;
+	struct menu_item *menu_item;
+	struct string_list_item *string_list_item;
+	int i;
+
+	switch (stuff->type) {
+	default:
+		die("Bad type of menu_staff when print menu");
+	case MENU_STUFF_TYPE_MENU_ITEM:
+		menu_item = (struct menu_item *)stuff->stuff;
+		for (i = 0; i < stuff->nr; i++, menu_item++) {
+			const char *p;
+			int highlighted = 0;
+
+			p = menu_item->title;
+			if ((*chosen)[i] < 0)
+				(*chosen)[i] = menu_item->selected ? 1 : 0;
+			strbuf_addf(&menu, "%s%2d: ", (*chosen)[i] ? "*" : " ", i+1);
+			for (; *p; p++) {
+				if (!highlighted && *p == menu_item->hotkey) {
+					strbuf_addstr(&menu, clean_get_color(CLEAN_COLOR_PROMPT));
+					strbuf_addch(&menu, *p);
+					strbuf_addstr(&menu, clean_get_color(CLEAN_COLOR_RESET));
+					highlighted = 1;
+				} else {
+					strbuf_addch(&menu, *p);
+				}
+			}
+			string_list_append(&menu_list, menu.buf);
+			strbuf_reset(&menu);
+		}
+		break;
+	case MENU_STUFF_TYPE_STRING_LIST:
+		i = 0;
+		for_each_string_list_item(string_list_item, (struct string_list *)stuff->stuff) {
+			if ((*chosen)[i] < 0)
+				(*chosen)[i] = 0;
+			strbuf_addf(&menu, "%s%2d: %s",
+				    (*chosen)[i] ? "*" : " ", i+1, string_list_item->string);
+			string_list_append(&menu_list, menu.buf);
+			strbuf_reset(&menu);
+			i++;
+		}
+		break;
+	}
+
+	pretty_print_menus(&menu_list);
+
+	strbuf_release(&menu);
+	strbuf_release(&buf);
+	string_list_clear(&menu_list, 0);
+}
+
+/*
+ * Parse user input, and return choice(s) for menu (menu_stuff).
+ *
+ * Input
+ *     (for single choice)
+ *         1          - select a numbered item
+ *         foo        - select item based on menu title
+ *                    - (empty) select nothing
+ *
+ *     (for multiple choice)
+ *         1          - select a single item
+ *         3-5        - select a range of items
+ *         2-3,6-9    - select multiple ranges
+ *         foo        - select item based on menu title
+ *         -...       - unselect specified items
+ *         *          - choose all items
+ *                    - (empty) finish selecting
+ *
+ * The parse result will be saved in array **chosen, and
+ * return number of total selections.
+ */
+static int parse_choice(struct menu_stuff *menu_stuff,
+			int is_single,
+			struct strbuf input,
+			int **chosen)
+{
+	struct strbuf **choice_list, **ptr;
+	struct menu_item *menu_item;
+	struct string_list_item *string_list_item;
+	int nr = 0;
+	int i;
+
+	if (is_single) {
+		choice_list = strbuf_split_max(&input, '\n', 0);
+	} else {
+		char *p = input.buf;
+		do {
+			if (*p == ',')
+				*p = ' ';
+		} while (*p++);
+		choice_list = strbuf_split_max(&input, ' ', 0);
+	}
+
+	for (ptr = choice_list; *ptr; ptr++) {
+		char *p;
+		int choose = 1;
+		int bottom = 0, top = 0;
+		int is_range, is_number;
+
+		strbuf_trim(*ptr);
+		if (!(*ptr)->len)
+			continue;
+
+		/* Input that begins with '-'; unchoose */
+		if (*(*ptr)->buf == '-') {
+			choose = 0;
+			strbuf_remove((*ptr), 0, 1);
+		}
+
+		is_range = 0;
+		is_number = 1;
+		for (p = (*ptr)->buf; *p; p++) {
+			if ('-' == *p) {
+				if (!is_range) {
+					is_range = 1;
+					is_number = 0;
+				} else {
+					is_number = 0;
+					is_range = 0;
+					break;
+				}
+			} else if (!isdigit(*p)) {
+				is_number = 0;
+				is_range = 0;
+				break;
+			}
+		}
+
+		if (is_number) {
+			bottom = atoi((*ptr)->buf);
+			top = bottom;
+		} else if (is_range) {
+			bottom = atoi((*ptr)->buf);
+			/* a range can be specified like 5-7 or 5- */
+			if (!*(strchr((*ptr)->buf, '-') + 1))
+				top = menu_stuff->nr;
+			else
+				top = atoi(strchr((*ptr)->buf, '-') + 1);
+		} else if (!strcmp((*ptr)->buf, "*")) {
+			bottom = 1;
+			top = menu_stuff->nr;
+		} else {
+			switch (menu_stuff->type) {
+			default:
+				die("Bad type of menu_stuff when parse choice");
+			case MENU_STUFF_TYPE_MENU_ITEM:
+				menu_item = (struct menu_item *)menu_stuff->stuff;
+				for (i = 0; i < menu_stuff->nr; i++, menu_item++) {
+					if (((*ptr)->len == 1 &&
+					     *(*ptr)->buf == menu_item->hotkey) ||
+					    !strcasecmp((*ptr)->buf, menu_item->title)) {
+						bottom = i + 1;
+						top = bottom;
+						break;
+					}
+				}
+				break;
+			case MENU_STUFF_TYPE_STRING_LIST:
+				string_list_item = ((struct string_list *)menu_stuff->stuff)->items;
+				for (i = 0; i < menu_stuff->nr; i++, string_list_item++) {
+					if (!strcasecmp((*ptr)->buf, string_list_item->string)) {
+						bottom = i + 1;
+						top = bottom;
+						break;
+					}
+				}
+				break;
+			}
+		}
+
+		if (top <= 0 || bottom <= 0 || top > menu_stuff->nr || bottom > top ||
+		    (is_single && bottom != top)) {
+			clean_print_color(CLEAN_COLOR_ERROR);
+			printf_ln(_("Huh (%s)?"), (*ptr)->buf);
+			clean_print_color(CLEAN_COLOR_RESET);
+			continue;
+		}
+
+		for (i = bottom; i <= top; i++)
+			(*chosen)[i-1] = choose;
+	}
+
+	strbuf_list_free(choice_list);
+
+	for (i = 0; i < menu_stuff->nr; i++)
+		nr += (*chosen)[i];
+	return nr;
+}
+
+/*
+ * Implement a git-add-interactive compatible UI, which is borrowed
+ * from git-add--interactive.perl.
+ *
+ * Return value:
+ *
+ *   - Return an array of integers
+ *   - , and it is up to you to free the allocated memory.
+ *   - The array ends with EOF.
+ *   - If user pressed CTRL-D (i.e. EOF), no selection returned.
+ */
+static int *list_and_choose(struct menu_opts *opts, struct menu_stuff *stuff)
+{
+	struct strbuf choice = STRBUF_INIT;
+	int *chosen, *result;
+	int nr = 0;
+	int eof = 0;
+	int i;
+
+	chosen = xmalloc(sizeof(int) * stuff->nr);
+	/* set chosen as uninitialized */
+	for (i = 0; i < stuff->nr; i++)
+		chosen[i] = -1;
+
+	for (;;) {
+		if (opts->header) {
+			printf_ln("%s%s%s",
+				  clean_get_color(CLEAN_COLOR_HEADER),
+				  _(opts->header),
+				  clean_get_color(CLEAN_COLOR_RESET));
+		}
+
+		/* chosen will be initialized by print_highlight_menu_stuff */
+		print_highlight_menu_stuff(stuff, &chosen);
+
+		if (opts->flags & MENU_OPTS_LIST_ONLY)
+			break;
+
+		if (opts->prompt) {
+			printf("%s%s%s%s",
+			       clean_get_color(CLEAN_COLOR_PROMPT),
+			       _(opts->prompt),
+			       opts->flags & MENU_OPTS_SINGLETON ? "> " : ">> ",
+			       clean_get_color(CLEAN_COLOR_RESET));
+		}
+
+		if (strbuf_getline(&choice, stdin, '\n') != EOF) {
+			strbuf_trim(&choice);
+		} else {
+			eof = 1;
+			break;
+		}
+
+		/* help for prompt */
+		if (!strcmp(choice.buf, "?")) {
+			prompt_help_cmd(opts->flags & MENU_OPTS_SINGLETON);
+			continue;
+		}
+
+		/* for a multiple-choice menu, press ENTER (empty) will return back */
+		if (!(opts->flags & MENU_OPTS_SINGLETON) && !choice.len)
+			break;
+
+		nr = parse_choice(stuff,
+				  opts->flags & MENU_OPTS_SINGLETON,
+				  choice,
+				  &chosen);
+
+		if (opts->flags & MENU_OPTS_SINGLETON) {
+			if (nr)
+				break;
+		} else if (opts->flags & MENU_OPTS_IMMEDIATE) {
+			break;
+		}
+	}
+
+	if (eof) {
+		result = xmalloc(sizeof(int));
+		*result = EOF;
+	} else {
+		int j = 0;
+
+		/*
+		 * recalculate nr, if return back from menu directly with
+		 * default selections.
+		 */
+		if (!nr) {
+			for (i = 0; i < stuff->nr; i++)
+				nr += chosen[i];
+		}
+
+		result = xmalloc(sizeof(int) * (nr + 1));
+		memset(result, 0, sizeof(int) * (nr + 1));
+		for (i = 0; i < stuff->nr && j < nr; i++) {
+			if (chosen[i])
+				result[j++] = i;
+		}
+		result[j] = EOF;
+	}
+
+	free(chosen);
+	strbuf_release(&choice);
+	return result;
+}
+
+static int clean_cmd(void)
+{
+	return MENU_RETURN_NO_LOOP;
+}
+
+static int filter_by_patterns_cmd(void)
+{
+	struct dir_struct dir;
+	struct strbuf confirm = STRBUF_INIT;
+	struct strbuf **ignore_list;
+	struct string_list_item *item;
+	struct exclude_list *el;
+	int changed = -1, i;
+
+	for (;;) {
+		if (!del_list.nr)
+			break;
+
+		if (changed)
+			pretty_print_dels();
+
+		clean_print_color(CLEAN_COLOR_PROMPT);
+		printf(_("Input ignore patterns>> "));
+		clean_print_color(CLEAN_COLOR_RESET);
+		if (strbuf_getline(&confirm, stdin, '\n') != EOF)
+			strbuf_trim(&confirm);
+		else
+			putchar('\n');
+
+		/* quit filter_by_pattern mode if press ENTER or Ctrl-D */
+		if (!confirm.len)
+			break;
+
+		memset(&dir, 0, sizeof(dir));
+		el = add_exclude_list(&dir, EXC_CMDL, "manual exclude");
+		ignore_list = strbuf_split_max(&confirm, ' ', 0);
+
+		for (i = 0; ignore_list[i]; i++) {
+			strbuf_trim(ignore_list[i]);
+			if (!ignore_list[i]->len)
+				continue;
+
+			add_exclude(ignore_list[i]->buf, "", 0, el, -(i+1));
+		}
+
+		changed = 0;
+		for_each_string_list_item(item, &del_list) {
+			int dtype = DT_UNKNOWN;
+
+			if (is_excluded(&dir, item->string, &dtype)) {
+				*item->string = '\0';
+				changed++;
+			}
+		}
+
+		if (changed) {
+			string_list_remove_empty_items(&del_list, 0);
+		} else {
+			clean_print_color(CLEAN_COLOR_ERROR);
+			printf_ln(_("WARNING: Cannot find items matched by: %s"), confirm.buf);
+			clean_print_color(CLEAN_COLOR_RESET);
+		}
+
+		strbuf_list_free(ignore_list);
+		clear_directory(&dir);
+	}
+
+	strbuf_release(&confirm);
+	return 0;
+}
+
+static int select_by_numbers_cmd(void)
+{
+	struct menu_opts menu_opts;
+	struct menu_stuff menu_stuff;
+	struct string_list_item *items;
+	int *chosen;
+	int i, j;
+
+	menu_opts.header = NULL;
+	menu_opts.prompt = N_("Select items to delete");
+	menu_opts.flags = 0;
+
+	menu_stuff.type = MENU_STUFF_TYPE_STRING_LIST;
+	menu_stuff.stuff = &del_list;
+	menu_stuff.nr = del_list.nr;
+
+	chosen = list_and_choose(&menu_opts, &menu_stuff);
+	items = del_list.items;
+	for (i = 0, j = 0; i < del_list.nr; i++) {
+		if (i < chosen[j]) {
+			*(items[i].string) = '\0';
+		} else if (i == chosen[j]) {
+			/* delete selected item */
+			j++;
+			continue;
+		} else {
+			/* end of chosen (chosen[j] == EOF), won't delete */
+			*(items[i].string) = '\0';
+		}
+	}
+
+	string_list_remove_empty_items(&del_list, 0);
+
+	free(chosen);
+	return 0;
+}
+
+static int ask_each_cmd(void)
+{
+	struct strbuf confirm = STRBUF_INIT;
+	struct strbuf buf = STRBUF_INIT;
+	struct string_list_item *item;
+	const char *qname;
+	int changed = 0, eof = 0;
+
+	for_each_string_list_item(item, &del_list) {
+		/* Ctrl-D should stop removing files */
+		if (!eof) {
+			qname = quote_path_relative(item->string, NULL, &buf);
+			printf(_("remove %s? "), qname);
+			if (strbuf_getline(&confirm, stdin, '\n') != EOF) {
+				strbuf_trim(&confirm);
+			} else {
+				putchar('\n');
+				eof = 1;
+			}
+		}
+		if (!confirm.len || strncasecmp(confirm.buf, "yes", confirm.len)) {
+			*item->string = '\0';
+			changed++;
+		}
+	}
+
+	if (changed)
+		string_list_remove_empty_items(&del_list, 0);
+
+	strbuf_release(&buf);
+	strbuf_release(&confirm);
+	return MENU_RETURN_NO_LOOP;
+}
+
+static int quit_cmd(void)
+{
+	string_list_clear(&del_list, 0);
+	printf_ln(_("Bye."));
+	return MENU_RETURN_NO_LOOP;
+}
+
+static int help_cmd(void)
+{
+	clean_print_color(CLEAN_COLOR_HELP);
+	printf_ln(_(
+		    "clean               - start cleaning\n"
+		    "filter by pattern   - exclude items from deletion\n"
+		    "select by numbers   - select items to be deleted by numbers\n"
+		    "ask each            - confirm each deletion (like \"rm -i\")\n"
+		    "quit                - stop cleaning\n"
+		    "help                - this screen\n"
+		    "?                   - help for prompt selection"
+		   ));
+	clean_print_color(CLEAN_COLOR_RESET);
+	return 0;
+}
+
+static void interactive_main_loop(void)
+{
+	while (del_list.nr) {
+		struct menu_opts menu_opts;
+		struct menu_stuff menu_stuff;
+		struct menu_item menus[] = {
+			{'c', "clean",			0, clean_cmd},
+			{'f', "filter by pattern",	0, filter_by_patterns_cmd},
+			{'s', "select by numbers",	0, select_by_numbers_cmd},
+			{'a', "ask each",		0, ask_each_cmd},
+			{'q', "quit",			0, quit_cmd},
+			{'h', "help",			0, help_cmd},
+		};
+		int *chosen;
+
+		menu_opts.header = N_("*** Commands ***");
+		menu_opts.prompt = N_("What now");
+		menu_opts.flags = MENU_OPTS_SINGLETON;
+
+		menu_stuff.type = MENU_STUFF_TYPE_MENU_ITEM;
+		menu_stuff.stuff = menus;
+		menu_stuff.nr = sizeof(menus) / sizeof(struct menu_item);
+
+		clean_print_color(CLEAN_COLOR_HEADER);
+		printf_ln(Q_("Would remove the following item:",
+			     "Would remove the following items:",
+			     del_list.nr));
+		clean_print_color(CLEAN_COLOR_RESET);
+
+		pretty_print_dels();
+
+		chosen = list_and_choose(&menu_opts, &menu_stuff);
+
+		if (*chosen != EOF) {
+			int ret;
+			ret = menus[*chosen].fn();
+			if (ret != MENU_RETURN_NO_LOOP) {
+				free(chosen);
+				chosen = NULL;
+				if (!del_list.nr) {
+					clean_print_color(CLEAN_COLOR_ERROR);
+					printf_ln(_("No more files to clean, exiting."));
+					clean_print_color(CLEAN_COLOR_RESET);
+					break;
+				}
+				continue;
+			}
+		} else {
+			quit_cmd();
+		}
+
+		free(chosen);
+		chosen = NULL;
+		break;
+	}
+}
+
 int cmd_clean(int argc, const char **argv, const char *prefix)
 {
 	int i, res;
 	int dry_run = 0, remove_directories = 0, quiet = 0, ignored = 0;
 	int ignored_only = 0, config_set = 0, errors = 0, gone = 1;
 	int rm_flags = REMOVE_DIR_KEEP_NESTED_GIT;
-	struct strbuf directory = STRBUF_INIT;
+	struct strbuf abs_path = STRBUF_INIT;
 	struct dir_struct dir;
 	static const char **pathspec;
 	struct strbuf buf = STRBUF_INIT;
 	struct string_list exclude_list = STRING_LIST_INIT_NODUP;
 	struct exclude_list *el;
+	struct string_list_item *item;
 	const char *qname;
 	char *seen = NULL;
 	struct option options[] = {
 		OPT__QUIET(&quiet, N_("do not print names of files removed")),
 		OPT__DRY_RUN(&dry_run, N_("dry run")),
 		OPT__FORCE(&force, N_("force")),
+		OPT_BOOL('i', "interactive", &interactive, N_("interactive cleaning")),
 		OPT_BOOLEAN('d', NULL, &remove_directories,
 				N_("remove whole directories")),
 		{ OPTION_CALLBACK, 'e', "exclude", &exclude_list, N_("pattern"),
@@ -186,12 +877,12 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 	if (ignored && ignored_only)
 		die(_("-x and -X cannot be used together"));
 
-	if (!dry_run && !force) {
+	if (!interactive && !dry_run && !force) {
 		if (config_set)
-			die(_("clean.requireForce set to true and neither -n nor -f given; "
+			die(_("clean.requireForce set to true and neither -i, -n nor -f given; "
 				  "refusing to clean"));
 		else
-			die(_("clean.requireForce defaults to true and neither -n nor -f given; "
+			die(_("clean.requireForce defaults to true and neither -i, -n nor -f given; "
 				  "refusing to clean"));
 	}
 
@@ -223,6 +914,7 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 		int matches = 0;
 		const struct cache_entry *ce;
 		struct stat st;
+		const char *rel;
 
 		/*
 		 * Remove the '/' at the end that directory
@@ -242,13 +934,8 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 				continue; /* Yup, this one exists unmerged */
 		}
 
-		/*
-		 * we might have removed this as part of earlier
-		 * recursive directory removal, so lstat() here could
-		 * fail with ENOENT.
-		 */
 		if (lstat(ent->name, &st))
-			continue;
+			die_errno("Cannot lstat '%s'", ent->name);
 
 		if (pathspec) {
 			memset(seen, 0, argc > 0 ? argc : 1);
@@ -257,33 +944,62 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 		}
 
 		if (S_ISDIR(st.st_mode)) {
-			strbuf_addstr(&directory, ent->name);
 			if (remove_directories || (matches == MATCHED_EXACTLY)) {
-				if (remove_dirs(&directory, prefix, rm_flags, dry_run, quiet, &gone))
-					errors++;
-				if (gone && !quiet) {
-					qname = quote_path_relative(directory.buf, directory.len, &buf, prefix);
-					printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
-				}
+				rel = relative_path(ent->name, prefix, &buf);
+				string_list_append(&del_list, rel);
 			}
-			strbuf_reset(&directory);
 		} else {
 			if (pathspec && !matches)
 				continue;
-			res = dry_run ? 0 : unlink(ent->name);
+			rel = relative_path(ent->name, prefix, &buf);
+			string_list_append(&del_list, rel);
+		}
+	}
+
+	if (interactive && del_list.nr > 0)
+		interactive_main_loop();
+
+	for_each_string_list_item(item, &del_list) {
+		struct stat st;
+
+		if (prefix)
+			strbuf_addstr(&abs_path, prefix);
+
+		strbuf_addstr(&abs_path, item->string);
+
+		/*
+		 * we might have removed this as part of earlier
+		 * recursive directory removal, so lstat() here could
+		 * fail with ENOENT.
+		 */
+		if (lstat(abs_path.buf, &st))
+			continue;
+
+		if (S_ISDIR(st.st_mode)) {
+			if (remove_dirs(&abs_path, prefix, rm_flags, dry_run, quiet, &gone))
+				errors++;
+			if (gone && !quiet) {
+				qname = quote_path_relative(item->string, NULL, &buf);
+				printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
+			}
+		} else {
+			res = dry_run ? 0 : unlink(abs_path.buf);
 			if (res) {
-				qname = quote_path_relative(ent->name, -1, &buf, prefix);
+				qname = quote_path_relative(item->string, NULL, &buf);
 				warning(_(msg_warn_remove_failed), qname);
 				errors++;
 			} else if (!quiet) {
-				qname = quote_path_relative(ent->name, -1, &buf, prefix);
+				qname = quote_path_relative(item->string, NULL, &buf);
 				printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
 			}
 		}
+		strbuf_reset(&abs_path);
 	}
 	free(seen);
 
-	strbuf_release(&directory);
+	strbuf_release(&abs_path);
+	strbuf_release(&buf);
+	string_list_clear(&del_list, 0);
 	string_list_clear(&exclude_list, 0);
 	return (errors != 0);
 }