gleak

name

gleak

description

gleak goroutine leak detection — capture a Goroutines() snapshot before a test, then Eventually(Goroutines).ShouldNot(HaveLeaked(snapshot)) to assert none leaked, with the BeforeEach/AfterEach/DeferCleanup pattern, ignoring matchers IgnoringTopFunction/IgnoringInBacktrace/IgnoringGoroutines/IgnoringCreator, well-known non-leaky goroutines, goroutine IDs, ReportFilenameWithPath, and the Ginkgo -p IgnoreGinkgoParallelClient gotcha. Use when a test must verify goroutines started during the test have all wound down and nothing leaked.

gleak: detecting leaked goroutines

gleak discovers all running goroutines and fails a test if any "leaked" — i.e. are still running after the test that aren't well-known framework/runtime goroutines and aren't on your ignore list. Docs: https://onsi.github.io/gomega/#gleak-finding-leaked-goroutines. Cross-refs: gomega:async, gomega:matchers.

gleak is an experimental Gomega package.

Import

import (
	. "github.com/onsi/gomega"
	"github.com/onsi/gomega/gleak" // often dot-imported too, for HaveLeaked/Goroutines/Ignoring*
)

The canonical pattern

Capture a baseline snapshot before the test; assert no leak after. The cleanup runs Eventually(Goroutines).ShouldNot(HaveLeaked(snapshot)):

BeforeEach(func() {
	goods := gleak.Goroutines()          // snapshot of "good" goroutines, taken now
	DeferCleanup( {
		Eventually(gleak.Goroutines).ShouldNot(gleak.HaveLeaked(goods))
	})
})