Always show which directory is not a git repository

Unify all

  fatal: Not a git repository

error messages so they include path information.
Signed-off-by: NRichard Hartmann <richih@net.in.tum.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

contrib/workdir/git-new-workdir

@@ -22,7 +22,7 @@ branch=$3
 # want to make sure that what is pointed to has a .git directory ...
 git_dir=$(cd "$orig_git" 2>/dev/null &&
   git rev-parse --git-dir 2>/dev/null) ||
-  die "\"$orig_git\" is not a git repository!"
+  die "Not a git repository: \"$orig_git\""
 
 case "$git_dir" in
 .git)

perl/Git.pm

@@ -204,14 +204,14 @@ sub repository {
 
 			unless (-d "$dir/refs" and -d "$dir/objects" and -e "$dir/HEAD") {
 				# Mimick git-rev-parse --git-dir error message:
-				throw Error::Simple('fatal: Not a git repository');
+				throw Error::Simple("fatal: Not a git repository: $dir");
 			}
 			my $search = Git->repository(Repository => $dir);
 			try {
 				$search->command('symbolic-ref', 'HEAD');
 			} catch Git::Error::Command with {
 				# Mimick git-rev-parse --git-dir error message:
-				throw Error::Simple('fatal: Not a git repository');
+				throw Error::Simple("fatal: Not a git repository: $dir");
 			}
 
 			$opts{Repository} = abs_path($dir);

setup.c

@@ -468,7 +468,7 @@ const char *setup_git_directory_gently(int *nongit_ok)
 				*nongit_ok = 1;
 				return NULL;
 			}
-			die("Not a git repository");
+			die("Not a git repository (or any of the parent directories): %s", DEFAULT_GIT_DIR_ENVIRONMENT);
 		}
 		if (chdir(".."))
 			die("Cannot change to %s/..: %s", cwd, strerror(errno));