[release-19.0] Fix crash in the evalengine (#17487)

go/vt/vtgate/evalengine/arena.go

@@ -61,6 +61,35 @@
 	return a.newEvalDecimalWithPrec(dec.Clamp(m-d, d), d)
 }
 
+<<<<<<< HEAD
+=======
+func (a *Arena) newEvalEnum(raw []byte, values *EnumSetValues) *evalEnum {
+	if cap(a.aEnum) > len(a.aEnum) {
+		a.aEnum = a.aEnum[:len(a.aEnum)+1]
+	} else {
+		a.aEnum = append(a.aEnum, evalEnum{})
+	}
+	val := &a.aEnum[len(a.aEnum)-1]
+	s := string(raw)
+	val.string = s
+	val.value = valueIdx(values, s)
+	return val
+}
+
+func (a *Arena) newEvalSet(raw []byte, values *EnumSetValues) *evalSet {
+	if cap(a.aSet) > len(a.aSet) {
+		a.aSet = a.aSet[:len(a.aSet)+1]
+	} else {
+		a.aSet = append(a.aSet, evalSet{})
+	}
+	val := &a.aSet[len(a.aSet)-1]
+	s := string(raw)
+	val.string = s
+	val.set = evalSetBits(values, s)
+	return val
+}
+
+>>>>>>> 06def14056 (Fix crash in the evalengine (#17487))
 func (a *Arena) newEvalBool(b bool) *evalInt64 {
 	if b {
 		return a.newEvalInt64(1)

go/vt/vtgate/evalengine/compiler_test.go

@@ -716,6 +716,20 @@ func TestCompilerSingle(t *testing.T) {
 			expression: `WEEK(timestamp '2024-01-01 10:34:58', 1)`,
 			result:     `INT64(1)`,
 		},
+		{
+			expression: `column0 + 1`,
+			values:     []sqltypes.Value{sqltypes.MakeTrusted(sqltypes.Enum, []byte("foo"))},
+			// Returns 0, as unknown enums evaluate here to -1. We have this test to
+			// exercise the path to push enums onto the stack.
+			result: `FLOAT64(0)`,
+		},
+		{
+			expression: `column0 + 1`,
+			values:     []sqltypes.Value{sqltypes.MakeTrusted(sqltypes.Set, []byte("foo"))},
+			// Returns 1, as unknown sets evaluate here to 0. We have this test to
+			// exercise the path to push sets onto the stack.
+			result: `FLOAT64(1)`,
+		},
 	}
 
 	tz, _ := time.LoadLocation("Europe/Madrid")