git-mergetool--lib.sh: add error message for unknown tool variant

In setup_tool, we check if the given tool is a known variant of a tool,
and quietly return with an error if not. This leads to the following
invocation quietly failing:

	git mergetool --tool=vimdiff4

Add an error message before returning in this case.

Signed-off-by: Philippe Blain <redacted>
Signed-off-by: Junio C Hamano <redacted>

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index d7e410d94814497d3e9428117f983a0b2f14458e..11ea181259f8654ec4600ae147eb9a6aa8445c39 100644 (file)
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -264,6 +264,7 @@ setup_tool () {
 
        if ! list_tool_variants | grep -q "^$tool$"
        then
+               echo "error: unknown tool variant '$tool'" >&2
                return 1
        fi