refactor: remove regex-match

internal/schema/schema.go

@@ -2,7 +2,6 @@ package schema
 
 import (
 	"fmt"
-	"regexp"
 	"text/scanner"
 
 	"github.com/graph-gophers/graphql-go/errors"
@@ -524,9 +523,6 @@ func parseDirectiveDef(l *common.Lexer) *types.DirectiveDefinition {
 
 	for {
 		loc := l.ConsumeIdent()
-		if ok, err := regexp.MatchString("^[A-Z][A-Z_]+$", loc); err != nil || !ok {
-			l.SyntaxError(fmt.Sprintf("expected directive location-spec to be SNAKE_CASE, but got %q", loc))
-		}
 		d.Locations = append(d.Locations, loc)
 		if l.Peek() != '|' {
 			break

internal/schema/schema_test.go

@@ -2,6 +2,7 @@ package schema_test
 
 import (
 	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/graph-gophers/graphql-go/internal/schema"
@@ -912,9 +913,9 @@ Second line of the description.
 			scalar MyScalar @mydirective
 			`,
 			validateError: func(err error) error {
-				msg := `graphql: syntax error: expected directive location-spec to be SNAKE_CASE, but got "on" (line 2, column 33)`
-				if err == nil || err.Error() != msg {
-					return fmt.Errorf("expected error %q, but got %q", msg, err)
+				prefix := `graphql: syntax error:`
+				if err == nil || !strings.HasPrefix(err.Error(), prefix) {
+					return fmt.Errorf("expected error starting with %q, but got %q", prefix, err)
 				}
 				return nil
 			},