launch_editor(): allow spaces in the filename

The construct

	sh -c "$0 \"$@\"" <editor> <file>

does not pick up quotes in <editor>, so you cannot give path to the
editor that has a shell IFS whitespace in it, and also give it initial
set of parameters and flags.  Replace $0 with <editor> to fix this issue.

This fixes

	git config core.editor '"c:/Program Files/What/Ever.exe"'

In other words, you can specify an editor with spaces in its path using a
config containing something like this:

	[core]
		editor = \"c:/Program Files/Darn/Spaces.exe\"

NOTE: we cannot just replace the $0 with \"$0\", because we still want
this to work:

	[core]
		editor = emacs -nw

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/t/t7005-editor.sh b/t/t7005-editor.sh
index c1cec55..6a74b3a 100755
--- a/t/t7005-editor.sh
+++ b/t/t7005-editor.sh
@@ -89,6 +89,33 @@ do
 	'
 done
 
+test_expect_success 'editor with a space' '
+
+	if echo "echo space > \"\$1\"" > "e space.sh"
+	then
+		chmod a+x "e space.sh" &&
+		GIT_EDITOR="./e\ space.sh" git commit --amend &&
+		test space = "$(git show -s --pretty=format:%s)"
+	else
+		say "Skipping; FS does not support spaces in filenames"
+	fi
+
+'
+
+unset GIT_EDITOR
+test_expect_success 'core.editor with a space' '
+
+	if test -f "e space.sh"
+	then
+		git config core.editor \"./e\ space.sh\" &&
+		git commit --amend &&
+		test space = "$(git show -s --pretty=format:%s)"
+	else
+		say "Skipping; FS does not support spaces in filenames"
+	fi
+
+'
+
 TERM="$OLD_TERM"
 
 test_done