require Go 1.18, add some generic helpers

Author: eli-darkly

.circleci/config.yml

@@ -7,20 +7,12 @@ workflows:
   workflow:
     jobs:
       - go-test:
-          name: Go 1.17
-          docker-image: cimg/go:1.17
+          name: Go 1.19
+          docker-image: cimg/go:1.19
+          run-lint: true
       - go-test:
-          name: Go 1.16
-          docker-image: cimg/go:1.16
-      - go-test:
-          name: Go 1.15
-          docker-image: cimg/go:1.15
-      - go-test:
-          name: Go 1.14
-          docker-image: cimg/go:1.14
-      - go-test:
-          name: Go 1.13
-          docker-image: cimg/go:1.13
+          name: Go 1.18
+          docker-image: cimg/go:1.18
       - go-test-windows:
           name: Windows
 
@@ -31,7 +23,7 @@ jobs:
         type: string
       run-lint:
         type: boolean
-        default: true
+        default: false
 
     docker:
       - image: <<parameters.docker-image>>
@@ -43,7 +35,7 @@ jobs:
       - checkout
       - run:
           name: install go-junit-report
-          command: go get -u github.com/jstemmer/go-junit-report
+          command: go install github.com/jstemmer/go-junit-report/[email protected]
 
       - when:
           condition: <<parameters.run-lint>>
@@ -74,6 +66,15 @@ jobs:
 
     steps:
       - checkout
+      - run: 
+          name: download Go 1.18.5
+          command: |
+            $ErrorActionPreference = "Stop"
+            $installerUrl = "https://go.dev/dl/go1.18.5.windows-amd64.msi"
+            (New-Object System.Net.WebClient).DownloadFile($installerUrl, "go1.18.5.windows-amd64.msi")
+      - run:
+          name: install Go 1.18.5
+          command: Start-Process msiexec.exe -Wait -ArgumentList "/I go1.18.5.windows-amd64.msi /quiet"
       - run: go version
       - run:
           name: build and test

.golangci.yml

@@ -18,20 +18,18 @@ linters:
     - godox
     - gofmt
     - goimports
-    - golint
     - gosec
     - gosimple
     - govet
     - ineffassign
-    - interfacer
     - lll
     - megacheck
     - misspell
     - nakedret
     - nolintlint
     - prealloc
+    - revive
     - staticcheck
-    - structcheck
     - stylecheck
     - typecheck
     - unconvert

.ldrelease/config.yml

@@ -2,12 +2,10 @@ version: 2
 
 jobs:
   - docker:
-      image: golang:1.13-buster
+      image: golang:1.18-buster
     template:
       name: go
-    env:
-      LD_RELEASE_GO_IMPORT_PATH: github.com/launchdarkly/go-test-helpers
 
 publications:
-  - url: https://pkg.go.dev/github.com/launchdarkly/go-test-helpers
+  - url: https://pkg.go.dev/github.com/launchdarkly/go-test-helpers/v2
     description: documentation

Makefile

@@ -1,5 +1,5 @@
 
-GOLANGCI_LINT_VERSION=v1.27.0
+GOLANGCI_LINT_VERSION=v1.48.0
 
 LINTER=./bin/golangci-lint
 LINTER_VERSION_FILE=./bin/.golangci-lint-version-$(GOLANGCI_LINT_VERSION)
@@ -17,7 +17,7 @@ test: build
 
 $(LINTER_VERSION_FILE):
 	rm -f $(LINTER)
-	curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s $(GOLANGCI_LINT_VERSION)
+	curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s $(GOLANGCI_LINT_VERSION)
 	touch $(LINTER_VERSION_FILE)
 
 lint: $(LINTER_VERSION_FILE)

README.md

@@ -6,7 +6,7 @@ This project centralizes some test support code that is used by LaunchDarkly's G
 
 While this code may be useful in other projects, it is primarily geared toward LaunchDarkly's own development needs and is not meant to provide a large general-purpose framework. It is meant for unit test code and should not be used as a runtime dependency.
 
-This version of the project requires Go 1.13 or higher.
+This version of the project requires Go 1.18 or higher.
 
 ## Contents
 

channels.go

@@ -0,0 +1,49 @@
+package helpers
+
+import (
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TryReceive returns the next value from the channel and true if successful, or returns an empty
+// value and false if the timeout expires first.
+func TryReceive[V any](ch <-chan V, timeout time.Duration) (V, bool) {
+	select {
+	case v := <-ch:
+		return v, true
+	case <-time.After(timeout):
+		var empty V
+		return empty, false
+	}
+}
+
+// RequireValue returns the next value from the channel, or forces an immediate test failure
+// and exit if the timeout expires first.
+func RequireValue[V any](t require.TestingT, ch <-chan V, timeout time.Duration) V {
+	if v, ok := TryReceive(ch, timeout); ok {
+		return v
+	}
+	var empty V
+	t.Errorf("expected a %T value from channel but did not receive one in %s", empty, timeout)
+	t.FailNow()
+	return empty // never reached
+}
+
+// AssertNoMoreValues asserts that no value is available from the channel within the timeout.
+func AssertNoMoreValues[V any](t assert.TestingT, ch <-chan V, timeout time.Duration) bool {
+	if v, ok := TryReceive(ch, timeout); ok {
+		t.Errorf("expected no more %T values from channel but got one: %+v", v, v)
+		return false
+	}
+	return true
+}
+
+// RequireNoMoreValues is equivalent to AssertNoMoreValues except that it forces an immediate
+// test exit on failure.
+func RequireNoMoreValues[V any](t require.TestingT, ch <-chan V, timeout time.Duration) {
+	if !AssertNoMoreValues(t, ch, timeout) {
+		t.FailNow()
+	}
+}

channels_test.go

@@ -0,0 +1,66 @@
+package helpers
+
+import (
+	"testing"
+	"time"
+
+	"github.com/launchdarkly/go-test-helpers/v2/testbox"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTryReceive(t *testing.T) {
+	ch := make(chan string, 1)
+	v, ok := TryReceive(ch, time.Millisecond)
+	assert.False(t, ok)
+	assert.Equal(t, "", v)
+
+	ch <- "a"
+	v, ok = TryReceive(ch, time.Millisecond)
+	assert.True(t, ok)
+	assert.Equal(t, "a", v)
+}
+
+func TestRequireValue(t *testing.T) {
+	result := testbox.SandboxTest(func(t1 testbox.TestingT) {
+		ch := make(chan string, 1)
+		_ = RequireValue(t1, ch, time.Millisecond)
+		t.Errorf("test should have exited early but did not")
+	})
+	assert.True(t, result.Failed)
+
+	ch := make(chan string, 1)
+	go func() {
+		ch <- "a"
+	}()
+	v := RequireValue(t, ch, time.Second)
+	assert.Equal(t, "a", v)
+}
+
+func TestAssertNoMoreValues(t *testing.T) {
+	ch := make(chan string, 1)
+	AssertNoMoreValues(t, ch, time.Millisecond)
+
+	result := testbox.SandboxTest(func(t testbox.TestingT) {
+		ch := make(chan string, 1)
+		go func() {
+			ch <- "a"
+		}()
+		AssertNoMoreValues(t, ch, time.Second)
+	})
+	assert.True(t, result.Failed)
+}
+
+func TestRequireNoMoreValues(t *testing.T) {
+	ch := make(chan string, 1)
+	AssertNoMoreValues(t, ch, time.Millisecond)
+
+	result := testbox.SandboxTest(func(t1 testbox.TestingT) {
+		ch := make(chan string, 1)
+		go func() {
+			ch <- "a"
+		}()
+		RequireNoMoreValues(t1, ch, time.Second)
+		t.Errorf("test should have exited early but did not")
+	})
+	assert.True(t, result.Failed)
+}

files.go

@@ -2,7 +2,6 @@ package helpers
 
 import (
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 )
@@ -20,11 +19,11 @@ func FilePathExists(path string) bool {
 // If deletion of the file fails (assuming it has not already been deleted) then an error is logged, but there is no
 // panic.
 //
-//     helpers.WithTempFile(func(path string) {
-//         DoSomethingWithTempFile(path)
-//     }) // the file is deleted at the end of this block
+//	helpers.WithTempFile(func(path string) {
+//		DoSomethingWithTempFile(path)
+//	}) // the file is deleted at the end of this block
 func WithTempFile(f func(string)) {
-	file, err := ioutil.TempFile("", "test")
+	file, err := os.CreateTemp("", "test")
 	if err != nil {
 		panic(fmt.Errorf("can't create temp file: %s", err))
 	}

go.mod

@@ -1,9 +1,11 @@
 module github.com/launchdarkly/go-test-helpers/v2
 
-go 1.13
+go 1.18
+
+require github.com/stretchr/testify v1.5.1
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/stretchr/testify v1.5.1
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	gopkg.in/yaml.v2 v2.2.8 // indirect
 )

go.sum

@@ -3,7 +3,6 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=