Changelog

May 26, 2026 · View on GitHub

Changelog for the selfie JVM libraries.

com.diffplug.selfie:selfie-lib:VERSION
com.diffplug.selfie:selfie-runner-junit5:VERSION
- can be used with JUnit4 via junit-vintage
- works with Kotest JVM
com.diffplug.selfie:selfie-runner-kotest:VERSION
- written in Kotlin Multiplatform The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

[Unreleased]

[3.1.1] - 2026-05-26

Fixed

ArrayMap no longer throws NumberFormatException for test case names containing very large numbers. (#577)

[3.1.0] - 2026-05-09

Added

SelfieSettingsAPI now has overridable testAnnotations and testSuperclasses properties which allow users with custom composed annotations or Spec-like base classes to register them. (#573)

[3.0.0] - 2026-03-02

Changed

BREAKING Bumped Kotest from 5.x to 6.x. If you need Kotest 5.x compatibility, stick with 2.5.5. (#559)
- This breaking change only affects Kotest users.
- As part of the Kotest 6.x migration, your AbstractProjectConfig must either have the fully qualified name of io.kotest.provided.ProjectConfig or the system property kotest.framework.config.fqn must be set. See Kotest docs for more info.
- The breaking changes are only within selfie-runner-kotest. So if you are stuck on Kotest 5.x but want some feature or bugfix only available in a 3.x version of Selfie, you can probably get it by grabbing the latest Selfie but using 2.5.5 for the selfie-runner-kotest artifact. But in the long-term, we recommend using the latest supported version of all dependencies.

[2.5.5] - 2025-11-22

Fixed

SnapshotFileLayout now computes root folder lazily. (#557 partial fix for #551)
- Allows parallel Maven execution with surefire and failsafe plugins with forkCount greater than one, but it only works if reuseForks set to false.

[2.5.4] - 2025-09-12

Fixed

Unsupported test sources (such as FieldSource) no longer cause the JUnit5 runner to crash. (#550 fixes #549)

Changed

Bump minimum required Kotest from 5.4.0 to 5.6.0 (#535)
- required to fix java.lang.NoSuchMethodError: 'long kotlin.time.Duration$Companion.milliseconds-UwyO8pc(long)'

[2.5.3] - 2025-05-21

Fixed

Restore support for JRE 11. (fixes #528)
snapshots created by junit.jupiter.api.TestFactory are no longer garbage-collected (#534)
support parallel testing under junit.jupiter.execution.parallel.enabled=true (#534)

[2.5.2] - 2025-04-28

Fixed

Off-by-one in the error message for a VCR key mismatch. (#526)
Fix StringIndexOutOfBoundsException when an empty snapshot had a facet added. (fixes #529)
Fix ClassCastException when multiple nested test cases need to update snapshot. (fixes #531)

[2.5.1] - 2025-03-04

Fixed

Selfie VCR is now out of beta, no opt-in required. (#525)
- ArrayMap now sorts strings with multi-digit numbers as 1 2 ... 9 10 11 instead of 1 11 2 ....
- Improved VCR-specific error messages for determining why //selfieonce might not be working for a test rule.
- Fixed some bugs in VCR data storage (specifically concurrency and multiple frames).

[2.5.0] - 2025-02-21

Added

Added an entrypoint Selfie.vcrTestLocator() for the new VcrSelfie class for snapshotting and replaying network traffic. (#517)

Fixed

Fixed a bug when saving facets containing keys with the ] character (#518)

[2.4.2] - 2025-01-01

Fixed

A single leading space (such as in the copyright header) should not override an otherwise 100% tab-indented file. (#506)

[2.4.1] - 2024-10-07

Fixed

Multiline toBe assertions (introduced in 2.1.0 for Java pre-15) were not throwing exceptions on snapshot mismatch, now fixed. (#479)

[2.4.0] - 2024-10-01

Added

Snapshot mismatch error messages now show a diff of the first mismatched line. (#477)

before

Snapshot mismatch
- update this snapshot by adding `_TODO` to the function name
- update all snapshots in this file by adding `//selfieonce` or `//SELFIEWRITE`

after

Snapshot mismatch at L7:C9
-Testing 123
+Testing ABC
‣ update this snapshot by adding `_TODO` to the function name
‣ update all snapshots in this file by adding `//selfieonce` or `//SELFIEWRITE`

[2.3.0] - 2024-07-11

Added

DiskSelfie now makes the Snapshot actual value public, so that other testing infrastructure can read from snapshotted values. (#467)

Fixed

cacheSelfie was missing @JvmOverloads on the methods with default arguments. (#425)

[2.2.1] - 2024-06-05

Fixed

Added Selfie.expectSelfies(Iterable<T> items, Function<T, String> toString) for doing easy "multi-asserts" in suspend fun also. (#421)

[2.2.0] - 2024-06-04

Added

SelfieSettingsAPI now has a field javaDontUseTripleQuoteLiterals which ensures that multiline strings are always encoded as " strings. (#417)

[2.1.0] - 2024-06-03

Added

Added Selfie.expectSelfies(Iterable<T> items, Function<T, String> toString) for doing easy "multi-asserts". (#416)
For java versions which don't support multiline string literals, we now encode multiline strings like so: (#406)
- ```
toBe("line1",
     "line2",
     "line3");
```

Changed

Bump Kotlin to 2.0.0. (#405)

Fixed

Do not remove stale snapshot files when readonly is true. (#367)
Provide more debugging info when a snapshot gets set multiple times. (helps with #370)

[2.0.2] - 2024-03-20

Fixed

toBeFile now checks for duplicate writes and throws a more helpful error message if the file doesn't exist. (#277)

[2.0.1] - 2024-02-24

Fixed

The coroutines methods used to eagerly throw an exception if they were ever called from anywhere besides a Kotest method. Now they wait until toMatchDisk() is called, because they can work just fine anywhere if you use toBe. (#247)

[2.0.0] - 2024-02-21

Added

Memoization (#219 implements #215)
- like expectSelfie, all are available as Selfie.cacheSelfie or as suspend fun in com.diffplug.selfie.coroutines.

val cachedResult: ByteArray = Selfie.cacheSelfieBinary { dalleJpeg() }.toBeFile("example.jpg")
val cachedResult: String    = Selfie.cacheSelfie { someString() }.toBe("what it was earlier")
val cachedResult: T         = Selfie.cacheSelfieJson { anyKotlinxSerializable() }.toBe("""{"key": "value"}""")
val cachedResult: T         = Selfie.cacheSelfieBinarySerializable { anyJavaIoSerializable() }.toMatchDisk()

toBeBase64 and toBeFile for true binary comparison of binary snapshots and facets. (#224)
spaces in multiline string literals aren't always escaped. (#220)
- if the leading spaces in the string literal match the file's existing indentation

Changed

BREAKING reordered a class hierarchy for better binary support. (#221)
- most users won't need to make any changes at all
- only exception is that expectSelfie(byte[]).toBe is now a compile error, must do toBeBase64

[1.2.0] - 2024-02-12

Added

Kotest support.
- Add SelfieExtension to your AbstractProjectConfig.
- Instead of calling Selfie.expectSelfie, call com.diffplug.selfie.coroutines.expectSelfie.
- selfie-runner-junit5 supports snapshots in regular JUnit tests and Kotest tests in the same project.
- selfie-runner-kotest is a new selfie implemented in Kotlin Multiplatform, but doesn't support snapshots within regular JUnit tests.
- Full docs at https://selfie.dev/jvm/kotest.

Fixed

Swap thread-local cache for thread-ignorant LRU to improve performance when used with coroutines. (#191)

Changes

(no user-facing changes) replaced terrible platform-specific Path with TypedPath. (#184)
(no user-facing changes) replaced SnapshotStorage with SnapshotSystem + DiskStorage. (#198)
(no user-facing changes) replaced most synchronized with CAS. (#199)

[1.1.2] - 2024-01-30

Fixed

@ParameterizedTest no longer has. (#140)
If a test class contained package-private methods and a single test method was run without the others, selfie would erroneously garbage collect disk snapshots for the other methods, now fixed. (#175 fixes #174)

[1.1.1] - 2024-01-25

Fixed

Selfie was erroneously garbage collecting snapshots when a test class contained no @Test public methods. (#124 fixes #123)

[1.1.0] - 2024-01-21

Added

Support for @ParameterizedTest. (#118)
ArraySet<K> has been added to the standard library alongside ArrayMap<K, V>. (#119)
- These have the strange property that if the key is String, then / characters are sorted to be the lowest possible character.

Fixed

We already smuggle errors from initialization to help debug them, and now we also smuggle errors that happen during test execution. (#117)
Fix a garbage collection bug which occurred when a test method's name was a prefix of another test method's name. (#119)