[RFC/PATCH] lockfile: improve error message when lockfile exists

From: Matthieu Moy <matthieu.moy@imag.fr>
Date: Feb 28, 2016, 20:11 UTC
Message-ID: <1456690276-13914-1-git-send-email-Matthieu.Moy@imag.fr>

A common mistake leading a user to see this message is to launch "git commit", let the editor open (and forget about it), and try again to commit.

The previous message was going too quickly to "a git process crashed" and to the advice "remove the file manually".

This patch modifies the message in two ways: first, it considers that "another process is running" is the norm, not the exception, and it explicitly hints the user to look at text editors.

The message is 2 lines longer, but this is not a problem since experienced users do not see the message often.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
---
This patch was written after seen one more time a student panicked
because he had a "git commit" backgrounded.

I'm not 100% satisfied with the new message. I don't think it harms to have a 5-lines message here but it's probably possible to be a bit more concise.

I'm the author of the previous version of the message, and I remember writting it after debugging a segfaut in Git which led me to see the message multiple times because of a crash. I guess that gave the wrong biais to the message ;-).

 lockfile.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lockfile.c b/lockfile.c
index 80d056d..a7d6175 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -150,9 +150,11 @@ void unable_to_lock_message(const char *path, int err, struct strbuf *buf)
 {
 	if (err == EEXIST) {
 		strbuf_addf(buf, "Unable to create '%s.lock': %s.\n\n"
-		    "If no other git process is currently running, this probably means a\n"
-		    "git process crashed in this repository earlier. Make sure no other git\n"
-		    "process is running and remove the file manually to continue.",
+		    "Another git process seems to be running in this repository.\n"
+		    "Please terminate it (e.g. quit any text editor that git may be\n"
+		    "waiting for) and try again. If no other git process is running,\n"
+		    "then a process may have crashed in this repository earlier:\n"
+		    "remove the file manually to continue.",
 			    absolute_path(path), strerror(err));
 	} else
 		strbuf_addf(buf, "Unable to create '%s.lock': %s",

-- 
2.7.2.334.g35ed2ae.dirty