Write correct synchronous Gomega assertions — Expect/Ω notation, the To/NotTo/ToNot/Should/ShouldNot equivalences, the multi-return error idiom, Succeed vs HaveOccurred, the .Error() chaining form, annotating assertions (format-string and func()string), tuning failure output via the format subpackage (MaxLength/MaxDepth/UseStringerRepresentation/GomegaStringer/TruncatedDiff/RegisterCustomFormatter/format.Object), and asserting inside helper functions with GinkgoHelper/WithOffset/ExpectWithOffset, NewWithT(t) for plain testing, and the g Gomega callback. Use when writing or reviewing synchronous (non-polling) Gomega assertions.
EnglishTesting streaming io buffers with gbytes — gbytes.NewBuffer() (an io.Writer also returned by gexec sessions), the Say(regexp) matcher that forward-scans from a moving read cursor, the canonical Eventually(buffer).Should(Say(...)) streaming pattern, sequential cursor-advancing Say calls, Contents(), BufferWithBytes/BufferReader, buffer.Detect for branching, and TimeoutReader/Writer/Closer for testing blocking io.Reader/Writer/Closer. Use when asserting on streaming or incremental output (process stdout/stderr, API streams, io.Readers) rather than a complete value.
EnglishTesting external processes with gexec — compile binaries with Build/BuildWithEnvironment/BuildIn and CleanupBuildArtifacts, start them with Start returning a Session, await exit with the Exit matcher (Eventually(session).Should(Exit(0))), Wait/ExitCode, signal via Kill/Terminate/Interrupt/Signal and package-level KillAndWait/TerminateAndWait, and assert on session.Out/Err which are gbytes buffers (Say, Contents). Use when building, running, signaling, or asserting on subprocesses in Go tests.
Englishgleak 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.
EnglishBenchmark and measure Go code with gmeasure — an Experiment groups named Measurements, recorded via RecordValue/RecordDuration/MeasureDuration or repeated Sample/SampleValue/SampleDuration with SamplingConfig, timed inline with a Stopwatch, summarized through GetStats/Stats (StatMin/Max/Mean/Median/StdDev, ValueFor/DurationFor) and compared with RankStats; decorate output with Units/Precision/Style/Annotation, render in Ginkgo via AddReportEntry, and persist with ExperimentCache. Use when you need human-readable benchmarks, performance reports, or regression baselines (not pass/fail assertions on their own).
EnglishDeep, partial matching of nested structs, slices, maps, and pointers with gstruct — MatchAllFields/MatchFields/Fields, MatchAllElements/MatchElements/Elements (idFn), MatchAllKeys/MatchKeys/Keys, PointTo, and the IgnoreExtras/IgnoreMissing/IgnoreUnexportedExtras/AllowDuplicates options, plus Ignore()/Reject(). Use when asserting against large or deeply nested data structures where you want to apply a different matcher to each field, element, or key.
EnglishThe complete catalog of Gomega's built-in matchers, grouped by category — equivalence (Equal/BeEquivalentTo/BeComparableTo/BeIdenticalTo/BeAssignableToTypeOf), presence (BeNil/BeZero/BeEmpty), truthiness (BeTrue/BeFalse/BeTrueBecause), errors (HaveOccurred/Succeed/MatchError), channels (Receive/BeClosed/BeSent), files, strings/JSON/XML/YAML, collections (ContainElement/ConsistOf/HaveExactElements/HaveKey), structs (HaveField), numbers/times (BeNumerically/BeTemporally), values (HaveValue), HTTP responses, and panics. Use when you need to find or choose the right matcher for an assertion instead of defaulting to Equal.
EnglishThe ghttp test HTTP server for testing HTTP clients — NewServer/NewTLSServer, AppendHandlers, the Verify assertions (VerifyRequest/VerifyHeader/VerifyHeaderKV/VerifyJSON/VerifyForm/VerifyBasicAuth/VerifyContentType/VerifyBody), RespondWith/RespondWithJSONEncoded(Ptr), CombineHandlers, RouteToHandler for unordered MUXed routes, AllowUnhandledRequests, RoundTripper, and TLS. Use when testing code that makes outbound HTTP requests.
NynorskIncludes Assertions and other workflows.
Supported by the Atlas install prompt. Skill-specific requirements vary.
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What’s included
Assertions
Write correct synchronous Gomega assertions — Expect/Ω notation, the To/NotTo/ToNot/Should/ShouldNot equivalences, the multi-return error idiom, Succeed vs HaveOccurred, the .Error() chaining form, annotating assertions (format-string and func()string), tuning failure output via the format subpackage (MaxLength/MaxDepth/UseStringerRepresentation/GomegaStringer/TruncatedDiff/RegisterCustomFormatter/format.Object), and asserting inside helper functions with GinkgoHelper/WithOffset/ExpectWithOffset, NewWithT(t) for plain testing, and the g Gomega callback. Use when writing or reviewing synchronous (non-polling) Gomega assertions.
Gbytes
Testing streaming io buffers with gbytes — gbytes.NewBuffer() (an io.Writer also returned by gexec sessions), the Say(regexp) matcher that forward-scans from a moving read cursor, the canonical Eventually(buffer).Should(Say(...)) streaming pattern, sequential cursor-advancing Say calls, Contents(), BufferWithBytes/BufferReader, buffer.Detect for branching, and TimeoutReader/Writer/Closer for testing blocking io.Reader/Writer/Closer. Use when asserting on streaming or incremental output (process stdout/stderr, API streams, io.Readers) rather than a complete value.
Gexec
Testing external processes with gexec — compile binaries with Build/BuildWithEnvironment/BuildIn and CleanupBuildArtifacts, start them with Start returning a Session, await exit with the Exit matcher (Eventually(session).Should(Exit(0))), Wait/ExitCode, signal via Kill/Terminate/Interrupt/Signal and package-level KillAndWait/TerminateAndWait, and assert on session.Out/Err which are gbytes buffers (Say, Contents). Use when building, running, signaling, or asserting on subprocesses in Go tests.
Gleak
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.
Gmeasure
Benchmark and measure Go code with gmeasure — an Experiment groups named Measurements, recorded via RecordValue/RecordDuration/MeasureDuration or repeated Sample/SampleValue/SampleDuration with SamplingConfig, timed inline with a Stopwatch, summarized through GetStats/Stats (StatMin/Max/Mean/Median/StdDev, ValueFor/DurationFor) and compared with RankStats; decorate output with Units/Precision/Style/Annotation, render in Ginkgo via AddReportEntry, and persist with ExperimentCache. Use when you need human-readable benchmarks, performance reports, or regression baselines (not pass/fail assertions on their own).
Gstruct
Deep, partial matching of nested structs, slices, maps, and pointers with gstruct — MatchAllFields/MatchFields/Fields, MatchAllElements/MatchElements/Elements (idFn), MatchAllKeys/MatchKeys/Keys, PointTo, and the IgnoreExtras/IgnoreMissing/IgnoreUnexportedExtras/AllowDuplicates options, plus Ignore()/Reject(). Use when asserting against large or deeply nested data structures where you want to apply a different matcher to each field, element, or key.
Matchers
The complete catalog of Gomega's built-in matchers, grouped by category — equivalence (Equal/BeEquivalentTo/BeComparableTo/BeIdenticalTo/BeAssignableToTypeOf), presence (BeNil/BeZero/BeEmpty), truthiness (BeTrue/BeFalse/BeTrueBecause), errors (HaveOccurred/Succeed/MatchError), channels (Receive/BeClosed/BeSent), files, strings/JSON/XML/YAML, collections (ContainElement/ConsistOf/HaveExactElements/HaveKey), structs (HaveField), numbers/times (BeNumerically/BeTemporally), values (HaveValue), HTTP responses, and panics. Use when you need to find or choose the right matcher for an assertion instead of defaulting to Equal.
Ghttp
The ghttp test HTTP server for testing HTTP clients — NewServer/NewTLSServer, AppendHandlers, the Verify assertions (VerifyRequest/VerifyHeader/VerifyHeaderKV/VerifyJSON/VerifyForm/VerifyBasicAuth/VerifyContentType/VerifyBody), RespondWith/RespondWithJSONEncoded(Ptr), CombineHandlers, RouteToHandler for unordered MUXed routes, AllowUnhandledRequests, RoundTripper, and TLS. Use when testing code that makes outbound HTTP requests.
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