Merge branch 'jk/bisect-final-output'

The final report from "git bisect" used to show the suspected
culprit using a raw "diff-tree", with which there is no output for
a merge commit.  This has been updated to use a more modern and
human readable output that still is concise enough.

* jk/bisect-final-output:
  bisect: make diff-tree output prettier
  bisect: fix internal diff-tree config loading
  bisect: use string arguments to feed internal diff-tree

bisect.c

@@ -896,24 +896,15 @@ static void show_diff_tree(struct repository *r,
 			   const char *prefix,
 			   struct commit *commit)
 {
+	const char *argv[] = {
+		"diff-tree", "--pretty", "--stat", "--summary", "--cc", NULL
+	};
 	struct rev_info opt;
 
-	/* diff-tree init */
+	git_config(git_diff_ui_config, NULL);
 	repo_init_revisions(r, &opt, prefix);
-	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
-	opt.abbrev = 0;
-	opt.diff = 1;
 
-	/* This is what "--pretty" does */
-	opt.verbose_header = 1;
-	opt.use_terminator = 0;
-	opt.commit_format = CMIT_FMT_DEFAULT;
-
-	/* diff-tree init */
-	if (!opt.diffopt.output_format)
-		opt.diffopt.output_format = DIFF_FORMAT_RAW;
-
-	setup_revisions(0, NULL, &opt, NULL);
+	setup_revisions(ARRAY_SIZE(argv) - 1, argv, &opt, NULL);
 	log_tree_commit(&opt, commit);
 }
 

t/t6030-bisect-porcelain.sh

@@ -681,7 +681,7 @@ test_expect_success 'bisect: --no-checkout - target in breakage' '
 	check_same BROKEN_HASH6 BISECT_HEAD &&
 	git bisect bad BISECT_HEAD &&
 	check_same BROKEN_HASH5 BISECT_HEAD &&
-	git bisect good BISECT_HEAD &&
+	test_must_fail git bisect good BISECT_HEAD &&
 	check_same BROKEN_HASH6 bisect/bad &&
 	git bisect reset
 '
@@ -692,7 +692,7 @@ test_expect_success 'bisect: --no-checkout - target after breakage' '
 	check_same BROKEN_HASH6 BISECT_HEAD &&
 	git bisect good BISECT_HEAD &&
 	check_same BROKEN_HASH8 BISECT_HEAD &&
-	git bisect good BISECT_HEAD &&
+	test_must_fail git bisect good BISECT_HEAD &&
 	check_same BROKEN_HASH9 bisect/bad &&
 	git bisect reset
 '
@@ -701,7 +701,7 @@ test_expect_success 'bisect: demonstrate identification of damage boundary' "
 	git bisect reset &&
 	git checkout broken &&
 	git bisect start broken master --no-checkout &&
-	git bisect run \"\$SHELL_PATH\" -c '
+	test_must_fail git bisect run \"\$SHELL_PATH\" -c '
 		GOOD=\$(git for-each-ref \"--format=%(objectname)\" refs/bisect/good-*) &&
 		git rev-list --objects BISECT_HEAD --not \$GOOD >tmp.\$\$ &&
 		git pack-objects --stdout >/dev/null < tmp.\$\$