• Migrate to NNBD.
    • Apis have been updated to express intent of the existing code and how it handled nulls.


  • Improve mismatch descriptions for deep matches. Previously, if the user tried to do a deep match where the expectation included a complex matcher (such as a “having” matcher), the failure message would just say “failed to match ...”; it wouldn‘t call on the expectation’s matcher to explain why the match failed.


  • Add a mismatch description to TypeMatcher.


  • Deprecate the mirror_matchers.dart library.


  • Update minimum Dart SDK to 2.2.0.
  • Consistently point to isA as a replacement for instanceOf.
  • Pretty print with private type names.


  • Add isA() to create TypeMatcher instances in a more fluent way.
  • Potentially breaking bug fix. Ordering matchers no longer treat objects with a partial ordering (such as NaN for double values) as if they had a complete ordering. For instance greaterThan now compares with the > operator rather not < and not =. This could cause tests which relied on this bug to start failing.


  • Add isCastError.


  • Set max SDK version to <3.0.0, and adjusted other dependencies.


  • Many improvements to TypeMatcher

    • Can now be used directly as const TypeMatcher<MyType>().

    • Added a type parameter to specify the target Type.

      • Made the name constructor parameter optional and marked it deprecated. It's redundant to the type parameter.
    • Migrated all isType matchers to TypeMatcher.

    • Added a having function that allows chained validations of specific features of the target type.

      /// Validates that the object is a [RangeError] with a message containing
      /// the string 'details' and `start` and `end` properties that are `null`.
      final _rangeMatcher = isRangeError
         .having((e) => e.message, 'message', contains('details'))
         .having((e) => e.start, 'start', isNull)
         .having((e) => e.end, 'end', isNull);
  • Deprecated the isInstanceOf class. Use TypeMatcher instead.

  • Improved the output of Matcher instances that fail due to type errors.


  • Updated SDK version to 2.0.0-dev.17.0


  • Fixed unorderedMatches in cases where the matchers may match more than one element and order of the elements doesn't line up with the order of the matchers.

  • Add containsAll matcher for Iterables. This Matcher checks that all values/matchers in an expected iterable are satisfied by an element in the value without allowing the same value to satisfy multiple matchers.


  • Fixed SDK constraint to allow edge builds.


  • Make predicate and pairwiseCompare generic methods to allow typed functions to be passed to them as arguments.

  • Make internal implementations take better advantage of type promotion to avoid dynamic call overhead.


  • Fixed small documentation issues.

  • Fixed small issue in StringEqualsMatcher.

  • Update to support future Dart language changes.


  • Produce a better error message when a CustomMatcher's feature throws.


  • Add containsAllInOrder matcher for Iterables


  • Fix all strong-mode warnings.


  • Fix test files to use test instead of unittest pkg.


  • Moved a number of members to the unittest package.

    • TestFailure, ErrorFormatter, expect, fail, and ‘wrapAsync’.
    • completes, completion, throws, and throwsA Matchers.
    • The Throws class.
    • All of the throws...Error Matchers.
  • Removed FailureHandler, DefaultFailureHandler, configureExpectFailureHandler, and getOrCreateExpectFailureHandler. Now that expect is in the unittest package, these are no longer needed.

  • Removed the name parameter for isInstanceOf. This was previously deprecated, and is no longer necessary since all language implementations now support converting the type parameter to a string directly.


  • Fix a bug introduced in 0.11.4+5 in which operator matchers broke when taking lists of matchers.


  • Fix all strong-mode warnings.


  • Deprecate the name parameter to isInstanceOf. All language implementations now support converting the type parameter to a string directly.


  • Fix the examples for equalsIgnoringWhitespace.


  • Improve the formatting of strings that contain unprintable ASCII characters.


  • Correctly match and print Strings containing characters that must be represented as escape sequences.


  • Remove the type checks in the isEmpty and isNotEmpty matchers and simply access the isEmpty respectively isNotEmpty fields. This allows them to work with custom collections. See Issue 21792 and Issue 21562


  • Fix the prints matcher test on dart2js.


  • Add a prints matcher that matches output a callback emits via print.


  • Add an isNotEmpty matcher.


  • Refactored libraries and tests.

  • Fixed spelling mistake.


  • Added isNaN and isNotNaN matchers.


  • Removed deprecated matchers.


  • Get the tests passing when run on dart2js in minified mode.


  • Compare sets order-independently when using equals().


  • Removed @deprecated annotation on matchers due to Issue 19173


  • Added types to a number of constants.


  • Matchers related to bad language use have been removed. These represent code structure that should rarely or never be validated in tests.

    • isAbstractClassInstantiationError
    • throwsAbstractClassInstantiationError
    • isFallThroughError
    • throwsFallThroughError
  • Added types to a number of method arguments.

  • The structure of the library and test code has been updated.