Fix string search.

utils/list.go

@@ -7,16 +7,16 @@ import (
 // StringsIsSubset checks that subset is strict subset of full, and returns
 // error formatted with errorFmt otherwise
 func StringsIsSubset(subset []string, full []string, errorFmt string) error {
-	for checked := range subset {
+	for _, checked := range subset {
 		found := false
-		for s := range full {
+		for _, s := range full {
 			if checked == s {
 				found = true
 				break
 			}
 		}
 		if !found {
-			return fmt.Errorf(errorFmt, checked, full)
+			return fmt.Errorf(errorFmt, checked)
 		}
 	}
 	return nil

utils/list_test.go

@@ -7,10 +7,12 @@ import (
 type ListSuite struct {
 }
 
+var _ = Suite(&ListSuite{})
+
 func (s *ListSuite) TestStringsIsSubset(c *C) {
 	err := StringsIsSubset([]string{"a", "b"}, []string{"a", "b", "c"}, "[%s]")
 	c.Assert(err, IsNil)
 
 	err = StringsIsSubset([]string{"b", "a"}, []string{"b", "c"}, "[%s]")
-	c.Assert(err, ErrorMatches, "[a]")
+	c.Assert(err, ErrorMatches, "\\[a\\]")
 }