parse: fix parsing optional arg with stdin

License: MIT
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>

commands/cli/parse.go

@@ -223,7 +223,7 @@ func parseArgs(inputs []string, stdin *os.File, argDefs []cmds.Argument, recursi
 	// if there is at least one ArgDef, we can safely trigger the inputs loop
 	// below to parse stdin.
 	numInputs := len(inputs)
-	if len(argDefs) > 0 && stdin != nil {
+	if len(argDefs) > 0 && argDefs[len(argDefs)-1].SupportsStdin && stdin != nil {
 		numInputs += 1
 	}
 

commands/cli/parse_test.go

@@ -283,4 +283,7 @@ func TestArgumentParsing(t *testing.T) {
 
 	fstdin = fileToSimulateStdin(t, "stdin1")
 	test([]string{"noarg"}, fstdin, []string{})
+
+	fstdin = fileToSimulateStdin(t, "stdin1")
+	test([]string{"optionalsecond", "value1", "value2"}, fstdin, []string{"value1", "value2"})
 }