parser: reset lexer.identifierDot correctly when reusing parsers (#45903) (#45908)

close #45898

Author: ti-chi-bot

parser/lexer.go

@@ -98,6 +98,7 @@ func (s *Scanner) reset(sql string) {
 	s.stmtStartPos = 0
 	s.inBangComment = false
 	s.lastKeyword = 0
+	s.identifierDot = false
 }
 
 func (s *Scanner) stmtText() string {

parser/parser_test.go

@@ -6722,3 +6722,15 @@ func TestNonTransactionalDelete(t *testing.T) {
 
 	RunTest(t, cases, false)
 }
+
+func TestIssue45898(t *testing.T) {
+	p := parser.New()
+	p.ParseSQL("a.")
+	stmts, _, err := p.ParseSQL("select count(1) from t")
+	require.NoError(t, err)
+	var sb strings.Builder
+	restoreCtx := NewRestoreCtx(DefaultRestoreFlags, &sb)
+	sb.Reset()
+	stmts[0].Restore(restoreCtx)
+	require.Equal(t, "SELECT COUNT(1) FROM `t`", sb.String())
+}