Add support for the `all` builtin (#54)

Implement the `all` as defined here:

* https://docs.python.org/2/library/functions.html#all

runtime/builtin_types.go

@@ -190,6 +190,31 @@ func builtinAbs(f *Frame, args Args, _ KWArgs) (*Object, *BaseException) {
 	return Abs(f, args[0])
 }
 
+func builtinAll(f *Frame, args Args, _ KWArgs) (*Object, *BaseException) {
+	if raised := checkFunctionArgs(f, "all", args, ObjectType); raised != nil {
+		return nil, raised
+	}
+	iter, raised := Iter(f, args[0])
+	if raised != nil {
+		return nil, raised
+	}
+	o, raised := Next(f, iter)
+	for ; raised == nil; o, raised = Next(f, iter) {
+		ret, raised := IsTrue(f, o)
+		if raised != nil {
+			return nil, raised
+		}
+		if !ret {
+			return False.ToObject(), nil
+		}
+	}
+	if !raised.isInstance(StopIterationType) {
+		return nil, raised
+	}
+	f.RestoreExc(nil, nil)
+	return True.ToObject(), nil
+}
+
 func builtinBin(f *Frame, args Args, _ KWArgs) (*Object, *BaseException) {
 	if raised := checkFunctionArgs(f, "bin", args, ObjectType); raised != nil {
 		return nil, raised
@@ -472,6 +497,7 @@ func init() {
 	builtinMap := map[string]*Object{
 		"__frame__":      newBuiltinFunction("__frame__", builtinFrame).ToObject(),
 		"abs":            newBuiltinFunction("abs", builtinAbs).ToObject(),
+		"all":            newBuiltinFunction("all", builtinAll).ToObject(),
 		"bin":            newBuiltinFunction("bin", builtinBin).ToObject(),
 		"chr":            newBuiltinFunction("chr", builtinChr).ToObject(),
 		"dir":            newBuiltinFunction("dir", builtinDir).ToObject(),

runtime/builtin_types_test.go

@@ -49,6 +49,21 @@ func TestBuiltinFuncs(t *testing.T) {
 			return NewInt(123).ToObject(), nil
 		}).ToObject(),
 	}))
+	badNonZeroType := newTestClass("BadNonZeroType", []*Type{ObjectType}, newStringDict(map[string]*Object{
+		"__nonzero__": newBuiltinFunction("__nonzero__", func(f *Frame, args Args, kwargs KWArgs) (*Object, *BaseException) {
+			return nil, f.RaiseType(RuntimeErrorType, "foo")
+		}).ToObject(),
+	}))
+	badNextType := newTestClass("BadNextType", []*Type{ObjectType}, newStringDict(map[string]*Object{
+		"next": newBuiltinFunction("next", func(f *Frame, args Args, kwargs KWArgs) (*Object, *BaseException) {
+			return nil, f.RaiseType(RuntimeErrorType, "foo")
+		}).ToObject(),
+	}))
+	badIterType := newTestClass("BadIterType", []*Type{ObjectType}, newStringDict(map[string]*Object{
+		"__iter__": newBuiltinFunction("__iter__", func(f *Frame, args Args, kwargs KWArgs) (*Object, *BaseException) {
+			return newObject(badNextType), nil
+		}).ToObject(),
+	}))
 	cases := []struct {
 		f       string
 		args    Args
@@ -65,6 +80,12 @@ func TestBuiltinFuncs(t *testing.T) {
 		{f: "abs", args: wrapArgs(NewFloat(-3.4)), want: NewFloat(3.4).ToObject()},
 		{f: "abs", args: wrapArgs(MinInt), want: NewLong(big.NewInt(MinInt).Neg(minIntBig)).ToObject()},
 		{f: "abs", args: wrapArgs(NewStr("a")), wantExc: mustCreateException(TypeErrorType, "bad operand type for abs(): 'str'")},
+		{f: "all", args: wrapArgs(newTestList()), want: True.ToObject()},
+		{f: "all", args: wrapArgs(newTestList(1, 2, 3)), want: True.ToObject()},
+		{f: "all", args: wrapArgs(newTestList(1, 0, 1)), want: False.ToObject()},
+		{f: "all", args: wrapArgs(13), wantExc: mustCreateException(TypeErrorType, "'int' object is not iterable")},
+		{f: "all", args: wrapArgs(newTestList(newObject(badNonZeroType))), wantExc: mustCreateException(RuntimeErrorType, "foo")},
+		{f: "all", args: wrapArgs(newObject(badIterType)), wantExc: mustCreateException(RuntimeErrorType, "foo")},
 		{f: "bin", args: wrapArgs(64 + 8 + 1), want: NewStr("0b1001001").ToObject()},
 		{f: "bin", args: wrapArgs(MinInt), want: NewStr(fmt.Sprintf("-0b%b0", -(MinInt >> 1))).ToObject()},
 		{f: "bin", args: wrapArgs(0), want: NewStr("0b0").ToObject()},

testing/builtin_test.py

@@ -34,3 +34,23 @@ except TypeError as e:
   assert str(e) == "bad operand type for abs(): 'str'"
 else:
   raise AssertionError('this was supposed to raise an exception')
+
+
+# all(iterable)
+
+assert all([1, 2, 3])
+assert all([])
+assert not all([1, 1, 1, 0, 1])
+
+assert all([True, True])
+assert not all([False, True, True])
+
+assert all('')
+assert all('abc')
+
+try:
+  all(13)
+except TypeError as e:
+  assert str(e) == "'int' object is not iterable"
+else:
+  raise AssertionError('this was supposed to raise an exception')