Implement complex hash. (#293)

Author: corona10

runtime/complex.go

@@ -72,6 +72,7 @@ func initComplexType(dict map[string]*Object) {
 	ComplexType.slots.Eq = &binaryOpSlot{complexEq}
 	ComplexType.slots.GE = &binaryOpSlot{complexCompareNotSupported}
 	ComplexType.slots.GT = &binaryOpSlot{complexCompareNotSupported}
+	ComplexType.slots.Hash = &unaryOpSlot{complexHash}
 	ComplexType.slots.LE = &binaryOpSlot{complexCompareNotSupported}
 	ComplexType.slots.LT = &binaryOpSlot{complexCompareNotSupported}
 	ComplexType.slots.NE = &binaryOpSlot{complexNE}
@@ -130,3 +131,12 @@ func complexCoerce(o *Object) (complex128, bool) {
 	}
 	return complex(floatO, 0.0), true
 }
+
+func complexHash(f *Frame, o *Object) (*Object, *BaseException) {
+	v := toComplexUnsafe(o).Value()
+	hashCombined := hashFloat(real(v)) + 1000003*hashFloat(imag(v))
+	if hashCombined == -1 {
+		hashCombined = -2
+	}
+	return NewInt(hashCombined).ToObject(), nil
+}

runtime/complex_test.go

@@ -93,3 +93,18 @@ func TestComplexRepr(t *testing.T) {
 		}
 	}
 }
+
+func TestComplexHash(t *testing.T) {
+	cases := []invokeTestCase{
+		{args: wrapArgs(complex(0.0, 0.0)), want: NewInt(0).ToObject()},
+		{args: wrapArgs(complex(0.0, 1.0)), want: NewInt(1000003).ToObject()},
+		{args: wrapArgs(complex(1.0, 0.0)), want: NewInt(1).ToObject()},
+		{args: wrapArgs(complex(3.1, -4.2)), want: NewInt(-1556830019620134).ToObject()},
+		{args: wrapArgs(complex(3.1, 4.2)), want: NewInt(1557030815934348).ToObject()},
+	}
+	for _, cas := range cases {
+		if err := runInvokeTestCase(wrapFuncForTest(complexHash), &cas); err != "" {
+			t.Error(err)
+		}
+	}
+}