Subject: Re: Doesn't disambiguate between 'external command failed' and 'command not found'

From: Michael Schubert <[email-masked]>
Date: Fri, 08 Jul 2011 12:08:49 +0200

On 07/07/2011 01:25 AM, Junio C Hamano wrote:
> Jeff King <[email-masked]> writes:
>> One minor nit, though. I haven't been paying attention to the progress
>> of the gettext topics, but should this message:
>>
>>> +static const char bad_interpreter_advice[] =
>>> +	"'%s' appears to be a git command, but we were not\n"
>>> +	"able to execute it. Maybe git-%s is broken?";
>>
>> Actually be inside _() for gettext?
> 
> I would mark it with N_() and then the calling site inside die() with _()
> if I were doing this.

Sorry for the delay.

-- >8 --

Subject: [PATCH] help_unknown_cmd: do not propose an "unknown" cmd

When executing an external shell script like `git foo` with the following
shebang "#!/usr/bin/not/existing", execvp returns 127 (ENOENT). Since
help_unknown_cmd proposes the use of all external commands similar to
the name of the "unknown" command, it suggests the just failed command
again. Stop it and give some advice to the user.

Helped-by: Jeff King <[email-masked]>
Signed-off-by: Michael Schubert <[email-masked]>
---
 help.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/help.c b/help.c
index 7654f1b..4219355 100644
--- a/help.c
+++ b/help.c
@@ -302,6 +302,10 @@ static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 #define SIMILARITY_FLOOR 7
 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 
+static const char bad_interpreter_advice[] =
+	N_("'%s' appears to be a git command, but we were not\n"
+	"able to execute it. Maybe git-%s is broken?");
+
 const char *help_unknown_cmd(const char *cmd)
 {
 	int i, n, best_similarity = 0;
@@ -326,6 +330,14 @@ const char *help_unknown_cmd(const char *cmd)
 		int cmp = 0; /* avoid compiler stupidity */
 		const char *candidate = main_cmds.names[i]->name;
 
+		/*
+		 * An exact match means we have the command, but
+		 * for some reason exec'ing it gave us ENOENT; probably
+		 * it's a bad interpreter in the #! line.
+		 */
+		if (!strcmp(candidate, cmd))
+			die(_(bad_interpreter_advice), cmd, cmd);
+
 		/* Does the candidate appear in common_cmds list? */
 		while (n < ARRAY_SIZE(common_cmds) &&
 		       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
-- 
1.7.6.132.g91c244.dirty