fix: initial checkin of v2

Signed-off-by: Dr. Carsten Leue <carsten.leue@de.ibm.com>

v2/context/readerioeither/reader_test.go

@@ -0,0 +1,286 @@
+// Copyright (c) 2023 IBM Corp.
+// All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package readerioeither
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	E "github.com/IBM/fp-go/v2/either"
+	F "github.com/IBM/fp-go/v2/function"
+	"github.com/IBM/fp-go/v2/internal/utils"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestInnerContextCancelSemantics(t *testing.T) {
+	// start with a simple context
+	outer := context.Background()
+
+	parent, parentCancel := context.WithCancel(outer)
+	defer parentCancel()
+
+	inner, innerCancel := context.WithCancel(parent)
+	defer innerCancel()
+
+	assert.NoError(t, parent.Err())
+	assert.NoError(t, inner.Err())
+
+	innerCancel()
+
+	assert.NoError(t, parent.Err())
+	assert.Error(t, inner.Err())
+
+}
+
+func TestOuterContextCancelSemantics(t *testing.T) {
+	// start with a simple context
+	outer := context.Background()
+
+	parent, outerCancel := context.WithCancel(outer)
+	defer outerCancel()
+
+	inner, innerCancel := context.WithCancel(parent)
+	defer innerCancel()
+
+	assert.NoError(t, parent.Err())
+	assert.NoError(t, inner.Err())
+
+	outerCancel()
+
+	assert.Error(t, parent.Err())
+	assert.Error(t, inner.Err())
+
+}
+
+func TestOuterAndInnerContextCancelSemantics(t *testing.T) {
+	// start with a simple context
+	outer := context.Background()
+
+	parent, outerCancel := context.WithCancel(outer)
+	defer outerCancel()
+
+	inner, innerCancel := context.WithCancel(parent)
+	defer innerCancel()
+
+	assert.NoError(t, parent.Err())
+	assert.NoError(t, inner.Err())
+
+	outerCancel()
+	innerCancel()
+
+	assert.Error(t, parent.Err())
+	assert.Error(t, inner.Err())
+
+	outerCancel()
+	innerCancel()
+
+	assert.Error(t, parent.Err())
+	assert.Error(t, inner.Err())
+}
+
+func TestCancelCauseSemantics(t *testing.T) {
+	// start with a simple context
+	outer := context.Background()
+
+	parent, outerCancel := context.WithCancelCause(outer)
+	defer outerCancel(nil)
+
+	inner := context.WithValue(parent, "key", "value")
+
+	assert.NoError(t, parent.Err())
+	assert.NoError(t, inner.Err())
+
+	err := fmt.Errorf("test error")
+
+	outerCancel(err)
+
+	assert.Error(t, parent.Err())
+	assert.Error(t, inner.Err())
+
+	assert.Equal(t, err, context.Cause(parent))
+	assert.Equal(t, err, context.Cause(inner))
+}
+
+func TestTimer(t *testing.T) {
+	delta := 3 * time.Second
+	timer := Timer(delta)
+	ctx := context.Background()
+
+	t0 := time.Now()
+	res := timer(ctx)()
+	t1 := time.Now()
+
+	assert.WithinDuration(t, t0.Add(delta), t1, time.Second)
+	assert.True(t, E.IsRight(res))
+}
+
+func TestCanceledApply(t *testing.T) {
+	// our error
+	err := fmt.Errorf("TestCanceledApply")
+	// the actual apply value errors out after some time
+	errValue := F.Pipe1(
+		Left[string](err),
+		Delay[string](time.Second),
+	)
+	// function never resolves
+	fct := Never[func(string) string]()
+	// apply the values, we expect an error after 1s
+
+	applied := F.Pipe1(
+		fct,
+		Ap[string, string](errValue),
+	)
+
+	res := applied(context.Background())()
+	assert.Equal(t, E.Left[string](err), res)
+}
+
+func TestRegularApply(t *testing.T) {
+	value := Of("Carsten")
+	fct := Of(utils.Upper)
+
+	applied := F.Pipe1(
+		fct,
+		Ap[string, string](value),
+	)
+
+	res := applied(context.Background())()
+	assert.Equal(t, E.Of[error]("CARSTEN"), res)
+}
+
+func TestWithResourceNoErrors(t *testing.T) {
+	var countAcquire, countBody, countRelease int
+
+	acquire := FromLazy(func() int {
+		countAcquire++
+		return countAcquire
+	})
+
+	release := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countRelease++
+			return countRelease
+		})
+	}
+
+	body := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countBody++
+			return countBody
+		})
+	}
+
+	resRIOE := WithResource[int](acquire, release)(body)
+
+	res := resRIOE(context.Background())()
+
+	assert.Equal(t, 1, countAcquire)
+	assert.Equal(t, 1, countBody)
+	assert.Equal(t, 1, countRelease)
+	assert.Equal(t, E.Of[error](1), res)
+}
+
+func TestWithResourceErrorInBody(t *testing.T) {
+	var countAcquire, countBody, countRelease int
+
+	acquire := FromLazy(func() int {
+		countAcquire++
+		return countAcquire
+	})
+
+	release := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countRelease++
+			return countRelease
+		})
+	}
+
+	err := fmt.Errorf("error in body")
+	body := func(int) ReaderIOEither[int] {
+		return Left[int](err)
+	}
+
+	resRIOE := WithResource[int](acquire, release)(body)
+
+	res := resRIOE(context.Background())()
+
+	assert.Equal(t, 1, countAcquire)
+	assert.Equal(t, 0, countBody)
+	assert.Equal(t, 1, countRelease)
+	assert.Equal(t, E.Left[int](err), res)
+}
+
+func TestWithResourceErrorInAcquire(t *testing.T) {
+	var countAcquire, countBody, countRelease int
+
+	err := fmt.Errorf("error in acquire")
+	acquire := Left[int](err)
+
+	release := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countRelease++
+			return countRelease
+		})
+	}
+
+	body := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countBody++
+			return countBody
+		})
+	}
+
+	resRIOE := WithResource[int](acquire, release)(body)
+
+	res := resRIOE(context.Background())()
+
+	assert.Equal(t, 0, countAcquire)
+	assert.Equal(t, 0, countBody)
+	assert.Equal(t, 0, countRelease)
+	assert.Equal(t, E.Left[int](err), res)
+}
+
+func TestWithResourceErrorInRelease(t *testing.T) {
+	var countAcquire, countBody, countRelease int
+
+	acquire := FromLazy(func() int {
+		countAcquire++
+		return countAcquire
+	})
+
+	err := fmt.Errorf("error in release")
+	release := func(int) ReaderIOEither[int] {
+		return Left[int](err)
+	}
+
+	body := func(int) ReaderIOEither[int] {
+		return FromLazy(func() int {
+			countBody++
+			return countBody
+		})
+	}
+
+	resRIOE := WithResource[int](acquire, release)(body)
+
+	res := resRIOE(context.Background())()
+
+	assert.Equal(t, 1, countAcquire)
+	assert.Equal(t, 1, countBody)
+	assert.Equal(t, 0, countRelease)
+	assert.Equal(t, E.Left[int](err), res)
+}