Merge branch 'dg/local-mod-error-messages'

* dg/local-mod-error-messages:
  t7609: test merge and checkout error messages
  unpack_trees: group error messages by type
  merge-recursive: distinguish "removed" and "overwritten" messages
  merge-recursive: porcelain messages for checkout
  Turn unpack_trees_options.msgs into an array + enum

Conflicts:
	t/t3400-rebase.sh

Documentation/technical/api-tree-walking.txt

@@ -42,6 +42,8 @@ information.
 
 * `data` can be anything the `fn` callback would want to use.
 
+* `show_all_errors` tells whether to stop at the first error or not.
+
 Initializing
 ------------
 

builtin/checkout.c

@@ -376,7 +376,7 @@ static int merge_working_tree(struct checkout_opts *opts,
 		topts.src_index = &the_index;
 		topts.dst_index = &the_index;
 
-		topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches.";
+		set_porcelain_error_msgs(topts.msgs, "checkout");
 
 		refresh_cache(REFRESH_QUIET);
 
@@ -395,6 +395,7 @@ static int merge_working_tree(struct checkout_opts *opts,
 		topts.dir = xcalloc(1, sizeof(*topts.dir));
 		topts.dir->flags |= DIR_SHOW_IGNORED;
 		topts.dir->exclude_per_dir = ".gitignore";
+		topts.show_all_errors = 1;
 		tree = parse_tree_indirect(old->commit ?
 					   old->commit->object.sha1 :
 					   (unsigned char *)EMPTY_TREE_SHA1_BIN);

builtin/merge.c

@@ -704,7 +704,8 @@ int checkout_fast_forward(const unsigned char *head, const unsigned char *remote
 	opts.verbose_update = 1;
 	opts.merge = 1;
 	opts.fn = twoway_merge;
-	opts.msgs = get_porcelain_error_msgs();
+	opts.show_all_errors = 1;
+	set_porcelain_error_msgs(opts.msgs, "merge");
 
 	trees[nr_trees] = parse_tree_indirect(head);
 	if (!trees[nr_trees++])

merge-recursive.c

@@ -179,7 +179,7 @@ static int git_merge_trees(int index_only,
 	opts.fn = threeway_merge;
 	opts.src_index = &the_index;
 	opts.dst_index = &the_index;
-	opts.msgs = get_porcelain_error_msgs();
+	set_porcelain_error_msgs(opts.msgs, "merge");
 
 	init_tree_desc_from_tree(t+0, common);
 	init_tree_desc_from_tree(t+1, head);
@@ -1173,26 +1173,48 @@ static int process_entry(struct merge_options *o,
 	return clean_merge;
 }
 
-struct unpack_trees_error_msgs get_porcelain_error_msgs(void)
+void set_porcelain_error_msgs(const char **msgs, const char *cmd)
 {
-	struct unpack_trees_error_msgs msgs = {
-		/* would_overwrite */
-		"Your local changes to '%s' would be overwritten by merge.  Aborting.",
-		/* not_uptodate_file */
-		"Your local changes to '%s' would be overwritten by merge.  Aborting.",
-		/* not_uptodate_dir */
-		"Updating '%s' would lose untracked files in it.  Aborting.",
-		/* would_lose_untracked */
-		"Untracked working tree file '%s' would be %s by merge.  Aborting",
-		/* bind_overlap -- will not happen here */
-		NULL,
-	};
-	if (advice_commit_before_merge) {
-		msgs.would_overwrite = msgs.not_uptodate_file =
-			"Your local changes to '%s' would be overwritten by merge.  Aborting.\n"
-			"Please, commit your changes or stash them before you can merge.";
-	}
-	return msgs;
+	const char *msg;
+	char *tmp;
+	const char *cmd2 = strcmp(cmd, "checkout") ? cmd : "switch branches";
+	if (advice_commit_before_merge)
+		msg = "Your local changes to the following files would be overwritten by %s:\n%%s"
+			"Please, commit your changes or stash them before you can %s.";
+	else
+		msg = "Your local changes to the following files would be overwritten by %s:\n%%s";
+	tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen(cmd2) - 2);
+	sprintf(tmp, msg, cmd, cmd2);
+	msgs[ERROR_WOULD_OVERWRITE] = tmp;
+	msgs[ERROR_NOT_UPTODATE_FILE] = tmp;
+
+	msgs[ERROR_NOT_UPTODATE_DIR] =
+		"Updating the following directories would lose untracked files in it:\n%s";
+
+	if (advice_commit_before_merge)
+		msg = "The following untracked working tree files would be %s by %s:\n%%s"
+			"Please move or remove them before you can %s.";
+	else
+		msg = "The following untracked working tree files would be %s by %s:\n%%s";
+	tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("removed") + strlen(cmd2) - 4);
+	sprintf(tmp, msg, "removed", cmd, cmd2);
+	msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] = tmp;
+	tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("overwritten") + strlen(cmd2) - 4);
+	sprintf(tmp, msg, "overwritten", cmd, cmd2);
+	msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] = tmp;
+
+	/*
+	 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
+	 * cannot easily display it as a list.
+	 */
+	msgs[ERROR_BIND_OVERLAP] = "Entry '%s' overlaps with '%s'.  Cannot bind.";
+
+	msgs[ERROR_SPARSE_NOT_UPTODATE_FILE] =
+		"Cannot update sparse checkout: the following entries are not up-to-date:\n%s";
+	msgs[ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN] =
+		"The following Working tree files would be overwritten by sparse checkout update:\n%s";
+	msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
+		"The following Working tree files would be removed by sparse checkout update:\n%s";
 }
 
 int merge_trees(struct merge_options *o,

merge-recursive.h

@@ -23,8 +23,11 @@ struct merge_options {
 	struct string_list current_directory_set;
 };
 
-/* Return a list of user-friendly error messages to be used by merge */
-struct unpack_trees_error_msgs get_porcelain_error_msgs(void);
+/*
+ * Sets the list of user-friendly error messages to be used by the
+ * command "cmd" (either merge or checkout)
+ */
+void set_porcelain_error_msgs(const char **msgs, const char *cmd);
 
 /* merge_trees() but with recursive ancestor consolidation */
 int merge_recursive(struct merge_options *o,

t/t3030-merge-recursive.sh

@@ -294,7 +294,7 @@ test_expect_success 'fail if the index has unresolved entries' '
 	grep "You have not concluded your merge" out &&
 	rm -f .git/MERGE_HEAD &&
 	test_must_fail git merge "$c5" 2> out &&
-	grep "Your local changes to .* would be overwritten by merge." out
+	grep "Your local changes to the following files would be overwritten by merge:" out
 '
 
 test_expect_success 'merge-recursive remove conflict' '

t/t3400-rebase.sh

@@ -153,7 +153,8 @@ test_expect_success 'setup: recover' '
 test_expect_success 'Show verbose error when HEAD could not be detached' '
 	>B &&
 	test_must_fail git rebase topic 2>output.err >output.out &&
-	grep "Untracked working tree file .B. would be overwritten" output.err
+	grep "The following untracked working tree files would be overwritten by checkout:" output.err &&
+	grep B output.err
 '
 rm -f B
 

t/t3404-rebase-interactive.sh

@@ -150,8 +150,9 @@ test_expect_success 'abort with error when new base cannot be checked out' '
 	git rm --cached file1 &&
 	git commit -m "remove file in base" &&
 	test_must_fail git rebase -i master > output 2>&1 &&
-	grep "Untracked working tree file .file1. would be overwritten" \
+	grep "The following untracked working tree files would be overwritten by checkout:" \
 		output &&
+	grep "file1" output &&
 	! test -d .git/rebase-merge &&
 	git reset --hard HEAD^
 '

t/t7609-merge-co-error-msgs.sh

@@ -0,0 +1,125 @@
+#!/bin/sh
+
+test_description='unpack-trees error messages'
+
+. ./test-lib.sh
+
+
+test_expect_success 'setup' '
+	echo one >one &&
+	git add one &&
+	git commit -a -m First &&
+
+	git checkout -b branch &&
+	echo two >two &&
+	echo three >three &&
+	echo four >four &&
+	echo five >five &&
+	git add two three four five &&
+	git commit -m Second &&
+
+	git checkout master &&
+	echo other >two &&
+	echo other >three &&
+	echo other >four &&
+	echo other >five
+'
+
+cat >expect <<\EOF
+error: The following untracked working tree files would be overwritten by merge:
+	two
+	three
+	four
+	five
+Please move or remove them before you can merge.
+EOF
+
+test_expect_success 'untracked files overwritten by merge' '
+	test_must_fail git merge branch 2>out &&
+	test_cmp out expect
+'
+
+cat >expect <<\EOF
+error: Your local changes to the following files would be overwritten by merge:
+	two
+	three
+	four
+Please, commit your changes or stash them before you can merge.
+error: The following untracked working tree files would be overwritten by merge:
+	five
+Please move or remove them before you can merge.
+EOF
+
+test_expect_success 'untracked files or local changes ovewritten by merge' '
+	git add two &&
+	git add three &&
+	git add four &&
+	test_must_fail git merge branch 2>out &&
+	test_cmp out expect
+'
+
+cat >expect <<\EOF
+error: Your local changes to the following files would be overwritten by checkout:
+	rep/two
+	rep/one
+Please, commit your changes or stash them before you can switch branches.
+EOF
+
+test_expect_success 'cannot switch branches because of local changes' '
+	git add five &&
+	mkdir rep &&
+	echo one >rep/one &&
+	echo two >rep/two &&
+	git add rep/one rep/two &&
+	git commit -m Fourth &&
+	git checkout master &&
+	echo uno >rep/one &&
+	echo dos >rep/two &&
+	test_must_fail git checkout branch 2>out &&
+	test_cmp out expect
+'
+
+cat >expect <<\EOF
+error: Your local changes to the following files would be overwritten by checkout:
+	rep/two
+	rep/one
+Please, commit your changes or stash them before you can switch branches.
+EOF
+
+test_expect_success 'not uptodate file porcelain checkout error' '
+	git add rep/one rep/two &&
+	test_must_fail git checkout branch 2>out &&
+	test_cmp out expect
+'
+
+cat >expect <<\EOF
+error: Updating the following directories would lose untracked files in it:
+	rep2
+	rep
+
+EOF
+
+test_expect_success 'not_uptodate_dir porcelain checkout error' '
+	git init uptodate &&
+	cd uptodate &&
+	mkdir rep &&
+	mkdir rep2 &&
+	touch rep/foo &&
+	touch rep2/foo &&
+	git add rep/foo rep2/foo &&
+	git commit -m init &&
+	git checkout -b branch &&
+	git rm rep -r &&
+	git rm rep2 -r &&
+	>rep &&
+	>rep2 &&
+	git add rep rep2&&
+	git commit -m "added test as a file" &&
+	git checkout master &&
+	>rep/untracked-file &&
+	>rep2/untracked-file &&
+	test_must_fail git checkout branch 2>out &&
+	test_cmp out ../expect
+'
+
+test_done

tree-walk.c

@@ -1,5 +1,6 @@
 #include "cache.h"
 #include "tree-walk.h"
+#include "unpack-trees.h"
 #include "tree.h"
 
 static const char *get_mode(const char *str, unsigned int *modep)
@@ -310,6 +311,7 @@ static void free_extended_entry(struct tree_desc_x *t)
 int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
 {
 	int ret = 0;
+	int error = 0;
 	struct name_entry *entry = xmalloc(n*sizeof(*entry));
 	int i;
 	struct tree_desc_x *tx = xcalloc(n, sizeof(*tx));
@@ -377,8 +379,11 @@ int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
 		if (!mask)
 			break;
 		ret = info->fn(n, mask, dirmask, entry, info);
-		if (ret < 0)
-			break;
+		if (ret < 0) {
+			error = ret;
+			if (!info->show_all_errors)
+				break;
+		}
 		mask &= ret;
 		ret = 0;
 		for (i = 0; i < n; i++)
@@ -389,7 +394,7 @@ int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
 	for (i = 0; i < n; i++)
 		free_extended_entry(tx + i);
 	free(tx);
-	return ret;
+	return error;
 }
 
 static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)

tree-walk.h

@@ -45,6 +45,7 @@ struct traverse_info {
 	unsigned long conflicts;
 	traverse_callback_t fn;
 	void *data;
+	int show_all_errors;
 };
 
 int get_tree_entry(const unsigned char *, const char *, unsigned char *, unsigned *);