github.com/google/grumpy@v0.0.0-20171122020858-3ec87959189c/runtime/generator_test.go (about)

     1  // Copyright 2016 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package grumpy
    16  
    17  import (
    18  	"testing"
    19  )
    20  
    21  func TestGeneratorNext(t *testing.T) {
    22  	f := NewRootFrame()
    23  	var recursive *Object
    24  	recursiveFn := func(*Object) (*Object, *BaseException) {
    25  		next, raised := GetAttr(f, recursive, NewStr("next"), nil)
    26  		if raised != nil {
    27  			return nil, raised
    28  		}
    29  		return next.Call(f, nil, nil)
    30  	}
    31  	recursive = NewGenerator(f, recursiveFn).ToObject()
    32  	emptyFn := func(*Object) (*Object, *BaseException) {
    33  		return nil, nil
    34  	}
    35  	exhausted := NewGenerator(NewRootFrame(), emptyFn).ToObject()
    36  	mustNotRaise(ListType.Call(NewRootFrame(), Args{exhausted}, nil))
    37  	cases := []invokeTestCase{
    38  		invokeTestCase{args: wrapArgs(recursive), wantExc: mustCreateException(ValueErrorType, "generator already executing")},
    39  		invokeTestCase{args: wrapArgs(exhausted), wantExc: toBaseExceptionUnsafe(mustNotRaise(StopIterationType.Call(NewRootFrame(), nil, nil)))},
    40  	}
    41  	for _, cas := range cases {
    42  		if err := runInvokeMethodTestCase(GeneratorType, "next", &cas); err != "" {
    43  			t.Error(err)
    44  		}
    45  	}
    46  }
    47  
    48  func TestGeneratorSend(t *testing.T) {
    49  	emptyFn := func(*Object) (*Object, *BaseException) {
    50  		return nil, nil
    51  	}
    52  	cases := []invokeTestCase{
    53  		invokeTestCase{args: wrapArgs(NewGenerator(NewRootFrame(), emptyFn), 123), wantExc: mustCreateException(TypeErrorType, "can't send non-None value to a just-started generator")},
    54  		invokeTestCase{args: wrapArgs(NewGenerator(NewRootFrame(), emptyFn), "foo", "bar"), wantExc: mustCreateException(TypeErrorType, "'send' of 'generator' requires 2 arguments")},
    55  	}
    56  	for _, cas := range cases {
    57  		if err := runInvokeMethodTestCase(GeneratorType, "send", &cas); err != "" {
    58  			t.Error(err)
    59  		}
    60  	}
    61  }
    62  
    63  func TestGeneratorSimple(t *testing.T) {
    64  	f := NewRootFrame()
    65  	fn := func(*Object) (*Object, *BaseException) {
    66  		switch f.State() {
    67  		case 0:
    68  			goto Start
    69  		case 1:
    70  			goto Yield1
    71  		case 2:
    72  			goto Yield2
    73  		default:
    74  			t.Fatalf("got invalid state %d", f.State())
    75  		}
    76  	Start:
    77  		f.PushCheckpoint(1)
    78  		return NewStr("foo").ToObject(), nil
    79  	Yield1:
    80  		f.PushCheckpoint(2)
    81  		return NewStr("bar").ToObject(), nil
    82  	Yield2:
    83  		return nil, nil
    84  	}
    85  	cas := &invokeTestCase{
    86  		args: wrapArgs(NewGenerator(f, fn)),
    87  		want: newTestList("foo", "bar").ToObject(),
    88  	}
    89  	if err := runInvokeTestCase(ListType.ToObject(), cas); err != "" {
    90  		t.Error(err)
    91  	}
    92  }