bisect--helper: string output variables together with "&&"

When doing:

eval "git bisect--helper --next-vars" | {
        while read line
        do
                echo "$line &&"
        done
        echo ':'
}

the result code comes from the last "echo ':'", not from running
"git bisect--helper --next-vars".

This patch gets rid of the need to string together the line from
the output of "git bisect--helper" with "&&" in the calling script
by making "git bisect--helper --next-vars" return output variables
already in that format.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

bisect.c

@@ -547,5 +547,6 @@ int bisect_next_vars(const char *prefix)
 	revs.commits = find_bisection(revs.commits, &reaches, &all,
 				      !!skipped_sha1_nr);
 
-	return show_bisect_vars(&revs, reaches, all, BISECT_SHOW_TRIED);
+	return show_bisect_vars(&revs, reaches, all,
+				BISECT_SHOW_TRIED | BISECT_SHOW_STRINGED);
 }

bisect.h

@@ -12,6 +12,7 @@ extern struct commit_list *filter_skipped(struct commit_list *list,
 /* show_bisect_vars flags */
 #define BISECT_SHOW_ALL		(1<<0)
 #define BISECT_SHOW_TRIED	(1<<1)
+#define BISECT_SHOW_STRINGED	(1<<2)
 
 /*
  * The flag BISECT_SHOW_ALL should not be set if this function is called

builtin-rev-list.c

@@ -226,20 +226,20 @@ static int estimate_bisect_steps(int all)
 	return (e < 3 * x) ? n : n - 1;
 }
 
-static void show_tried_revs(struct commit_list *tried)
+static void show_tried_revs(struct commit_list *tried, int stringed)
 {
 	printf("bisect_tried='");
 	for (;tried; tried = tried->next) {
 		char *format = tried->next ? "%s|" : "%s";
 		printf(format, sha1_to_hex(tried->item->object.sha1));
 	}
-	printf("'\n");
+	printf(stringed ? "' &&\n" : "'\n");
 }
 
 int show_bisect_vars(struct rev_info *revs, int reaches, int all, int flags)
 {
 	int cnt;
-	char hex[41] = "";
+	char hex[41] = "", *format;
 	struct commit_list *tried;
 
 	if (!revs->commits && !(flags & BISECT_SHOW_TRIED))
@@ -269,13 +269,22 @@ int show_bisect_vars(struct rev_info *revs, int reaches, int all, int flags)
 	}
 
 	if (flags & BISECT_SHOW_TRIED)
-		show_tried_revs(tried);
-	printf("bisect_rev=%s\n"
-	       "bisect_nr=%d\n"
-	       "bisect_good=%d\n"
-	       "bisect_bad=%d\n"
-	       "bisect_all=%d\n"
-	       "bisect_steps=%d\n",
+		show_tried_revs(tried, flags & BISECT_SHOW_STRINGED);
+	format = (flags & BISECT_SHOW_STRINGED) ?
+		"bisect_rev=%s &&\n"
+		"bisect_nr=%d &&\n"
+		"bisect_good=%d &&\n"
+		"bisect_bad=%d &&\n"
+		"bisect_all=%d &&\n"
+		"bisect_steps=%d\n"
+		:
+		"bisect_rev=%s\n"
+		"bisect_nr=%d\n"
+		"bisect_good=%d\n"
+		"bisect_bad=%d\n"
+		"bisect_all=%d\n"
+		"bisect_steps=%d\n";
+	printf(format,
 	       hex,
 	       cnt - 1,
 	       all - reaches - 1,

git-bisect.sh

@@ -279,18 +279,6 @@ bisect_auto_next() {
 	bisect_next_check && bisect_next || :
 }
 
-eval_and_string_together() {
-	_eval="$1"
-
-	eval "$_eval" | {
-		while read line
-		do
-			echo "$line &&"
-		done
-		echo ':'
-	}
-}
-
 exit_if_skipped_commits () {
 	_tried=$1
 	_bad=$2
@@ -429,8 +417,7 @@ bisect_next() {
 	test "$?" -eq "1" && return
 
 	# Get bisection information
-	eval="git bisect--helper --next-vars" &&
-	eval=$(eval_and_string_together "$eval") &&
+	eval=$(eval "git bisect--helper --next-vars") &&
 	eval "$eval" || exit
 
 	if [ -z "$bisect_rev" ]; then