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Diffstat (limited to 'dependencies/pkg/mod/golang.org/x/sync@v0.0.0-20210220032951-036812b2e83c/errgroup/errgroup_test.go')
-rw-r--r--dependencies/pkg/mod/golang.org/x/sync@v0.0.0-20210220032951-036812b2e83c/errgroup/errgroup_test.go176
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diff --git a/dependencies/pkg/mod/golang.org/x/sync@v0.0.0-20210220032951-036812b2e83c/errgroup/errgroup_test.go b/dependencies/pkg/mod/golang.org/x/sync@v0.0.0-20210220032951-036812b2e83c/errgroup/errgroup_test.go
new file mode 100644
index 0000000..5a0b9cb
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+++ b/dependencies/pkg/mod/golang.org/x/sync@v0.0.0-20210220032951-036812b2e83c/errgroup/errgroup_test.go
@@ -0,0 +1,176 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errgroup_test
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "net/http"
+ "os"
+ "testing"
+
+ "golang.org/x/sync/errgroup"
+)
+
+var (
+ Web = fakeSearch("web")
+ Image = fakeSearch("image")
+ Video = fakeSearch("video")
+)
+
+type Result string
+type Search func(ctx context.Context, query string) (Result, error)
+
+func fakeSearch(kind string) Search {
+ return func(_ context.Context, query string) (Result, error) {
+ return Result(fmt.Sprintf("%s result for %q", kind, query)), nil
+ }
+}
+
+// JustErrors illustrates the use of a Group in place of a sync.WaitGroup to
+// simplify goroutine counting and error handling. This example is derived from
+// the sync.WaitGroup example at https://golang.org/pkg/sync/#example_WaitGroup.
+func ExampleGroup_justErrors() {
+ g := new(errgroup.Group)
+ var urls = []string{
+ "http://www.golang.org/",
+ "http://www.google.com/",
+ "http://www.somestupidname.com/",
+ }
+ for _, url := range urls {
+ // Launch a goroutine to fetch the URL.
+ url := url // https://golang.org/doc/faq#closures_and_goroutines
+ g.Go(func() error {
+ // Fetch the URL.
+ resp, err := http.Get(url)
+ if err == nil {
+ resp.Body.Close()
+ }
+ return err
+ })
+ }
+ // Wait for all HTTP fetches to complete.
+ if err := g.Wait(); err == nil {
+ fmt.Println("Successfully fetched all URLs.")
+ }
+}
+
+// Parallel illustrates the use of a Group for synchronizing a simple parallel
+// task: the "Google Search 2.0" function from
+// https://talks.golang.org/2012/concurrency.slide#46, augmented with a Context
+// and error-handling.
+func ExampleGroup_parallel() {
+ Google := func(ctx context.Context, query string) ([]Result, error) {
+ g, ctx := errgroup.WithContext(ctx)
+
+ searches := []Search{Web, Image, Video}
+ results := make([]Result, len(searches))
+ for i, search := range searches {
+ i, search := i, search // https://golang.org/doc/faq#closures_and_goroutines
+ g.Go(func() error {
+ result, err := search(ctx, query)
+ if err == nil {
+ results[i] = result
+ }
+ return err
+ })
+ }
+ if err := g.Wait(); err != nil {
+ return nil, err
+ }
+ return results, nil
+ }
+
+ results, err := Google(context.Background(), "golang")
+ if err != nil {
+ fmt.Fprintln(os.Stderr, err)
+ return
+ }
+ for _, result := range results {
+ fmt.Println(result)
+ }
+
+ // Output:
+ // web result for "golang"
+ // image result for "golang"
+ // video result for "golang"
+}
+
+func TestZeroGroup(t *testing.T) {
+ err1 := errors.New("errgroup_test: 1")
+ err2 := errors.New("errgroup_test: 2")
+
+ cases := []struct {
+ errs []error
+ }{
+ {errs: []error{}},
+ {errs: []error{nil}},
+ {errs: []error{err1}},
+ {errs: []error{err1, nil}},
+ {errs: []error{err1, nil, err2}},
+ }
+
+ for _, tc := range cases {
+ g := new(errgroup.Group)
+
+ var firstErr error
+ for i, err := range tc.errs {
+ err := err
+ g.Go(func() error { return err })
+
+ if firstErr == nil && err != nil {
+ firstErr = err
+ }
+
+ if gErr := g.Wait(); gErr != firstErr {
+ t.Errorf("after %T.Go(func() error { return err }) for err in %v\n"+
+ "g.Wait() = %v; want %v",
+ g, tc.errs[:i+1], err, firstErr)
+ }
+ }
+ }
+}
+
+func TestWithContext(t *testing.T) {
+ errDoom := errors.New("group_test: doomed")
+
+ cases := []struct {
+ errs []error
+ want error
+ }{
+ {want: nil},
+ {errs: []error{nil}, want: nil},
+ {errs: []error{errDoom}, want: errDoom},
+ {errs: []error{errDoom, nil}, want: errDoom},
+ }
+
+ for _, tc := range cases {
+ g, ctx := errgroup.WithContext(context.Background())
+
+ for _, err := range tc.errs {
+ err := err
+ g.Go(func() error { return err })
+ }
+
+ if err := g.Wait(); err != tc.want {
+ t.Errorf("after %T.Go(func() error { return err }) for err in %v\n"+
+ "g.Wait() = %v; want %v",
+ g, tc.errs, err, tc.want)
+ }
+
+ canceled := false
+ select {
+ case <-ctx.Done():
+ canceled = true
+ default:
+ }
+ if !canceled {
+ t.Errorf("after %T.Go(func() error { return err }) for err in %v\n"+
+ "ctx.Done() was not closed",
+ g, tc.errs)
+ }
+ }
+}