[PATCH 2/4] am: read interactive input from stdin

[Jeff King <peff@peff.net>]

In the conversion of git-am from shell script to C, we switched to using
git_prompt(). Unlike the original shell command "read reply", this
doesn't read from stdin at all, but rather from /dev/tty.

In most cases this distinction wouldn't matter. We require (as the shell
script did) that stdin is a tty, so they would generally be the same
thing. But one important exception is our test suite: even with
test_terminal, we cannot test "am --interactive" because it insists on
reading from /dev/tty, not the pseudo-tty we've set up in the test
script.

Fixing this clears the way to adding tests in a future patch.

Signed-off-by: Jeff King <peff@peff.net>
---
Part of me dies inside when I look at adding the magical "64". But we
expect this input to be single-line (or at most, somebody might actually
type out "edit", etc), and avoiding strbuf_getline() saves us from
having to free the strbuf in the many early return paths. I dunno. If
it's too ugly it would not be too hard to switch it over.

 builtin/am.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/builtin/am.c b/builtin/am.c
index 644bb11f6c..47ad7a5a70 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1647,7 +1647,7 @@ static int do_interactive(struct am_state *state)
 		die(_("cannot be interactive without stdin connected to a terminal."));
 
 	for (;;) {
-		const char *reply;
+		char reply[64];
 
 		puts(_("Commit Body is:"));
 		puts("--------------------------");
@@ -1659,7 +1659,9 @@ static int do_interactive(struct am_state *state)
 		 * in your translation. The program will only accept English
 		 * input at this point.
 		 */
-		reply = git_prompt(_("Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all: "), PROMPT_ECHO);
+		printf(_("Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all: "));
+		if (!fgets(reply, sizeof(reply), stdin))
+			die("unable to read from stdin; aborting");
 
 		if (*reply == 'y' || *reply == 'Y') {
 			return 0;
-- 
2.22.0.rc1.539.g7bfcdfe86d