ranger: fix incorrect enum range for xxx_ci collation

util/ranger/points.go

@@ -460,7 +460,7 @@ func handleEnumFromBinOp(sc *stmtctx.StatementContext, ft *types.FieldType, val
 	for i := range ft.Elems {
 		tmpEnum.Name = ft.Elems[i]
 		tmpEnum.Value = uint64(i) + 1
-		d := types.NewMysqlEnumDatum(tmpEnum)
+		d := types.NewCollateMysqlEnumDatum(tmpEnum, ft.Collate)
 		if v, err := d.CompareDatum(sc, &val); err == nil {
 			switch op {
 			case ast.LT:

util/ranger/ranger_test.go

@@ -347,12 +347,14 @@ create table t(
 	d varchar(10),
 	e binary(10),
 	f varchar(10) collate utf8mb4_general_ci,
+	g enum('A','B','C') collate utf8mb4_general_ci,
 	index idx_ab(a(50), b),
 	index idx_cb(c, a),
 	index idx_d(d(2)),
 	index idx_e(e(2)),
 	index idx_f(f),
-	index idx_de(d(2), e)
+	index idx_de(d(2), e),
+	index idx_g(g)
 )`)
 
 	tests := []struct {
@@ -628,6 +630,13 @@ create table t(
 			filterConds: "[in(test.t.d, aab, aac)]",
 			resultStr:   "[[\"aa\" 0x61,\"aa\" 0x61]]",
 		},
+		{
+			indexPos:    6,
+			exprStr:     "g = 'a'",
+			accessConds: "[eq(test.t.g, a)]",
+			filterConds: "[]",
+			resultStr:   "[[\"A\",\"A\"]]",
+		},
 	}
 
 	collate.SetNewCollationEnabledForTest(true)