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  • Generating assertions for objects that implement functional interfaces
  • Shorter unique names for run configurations
  • Diffblue Cover Community Edition is available for use with commercial code
  • Feedback
  • How do I automatically maintain all of these tests?
  • Enhancements
  • Resolved Issues
  • Known Issues

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  1. Updates & Upgrades
  2. Release archive

2021-06-02

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Last updated 1 year ago

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Generating assertions for objects that implement functional interfaces

Diffblue Cover now produces tests for methods that return objects with types such as Function, BiFunction, IntPredicate etc. It can write tests for methods returning objects whose type is a functional interface type, as defined in .

For code written in a functional programming style, this means a significant increase in coverage.

Shorter unique names for run configurations

Run configuration names have been shortened whilst maintaining their uniqueness. This ensures both class and method names are easier to read. The new standard for method names no longer includes a signature and is in the format: simple class name . method name.

​​​​​

Diffblue Cover Community Edition is available for use with commercial code

Community Edition allows you to write tests for both open source and commercial code. This means you can now use Diffblue Cover Community Edition at work completely for free. Visit our documentation to learn more about how you can use Diffblue Cover at work, and also see our {: target="_blank" rel="noopener"}.

Feedback

If you have feedback, questions or requests regarding the Diffblue Cover IntelliJ Plugin, please contact us on the . We would love to hear about what is important to you and what you would like to see in upcoming releases.

How do I automatically maintain all of these tests?

Enhancements

  • Cover now writes assertions for equals methods with unequal objects as parameters. [Ref: TG-14662]

  • Cover now writes assertions for methods with a 'functional interface' return value, such as IntPredicate, Function or Supplier. [Ref: TG-13579]

  • Cover now provides more understandable and user-friendly error reporting to help diagnose and resolve issues. [Ref: TG-13589]

  • CLI: The configuration file format for Cover has now been simplified, allowing command line options to be supplied in a text file, e.g. config.txt, which can be referenced by running dcover create @config.txt. This replaces the existing --config and --example-config options for supplying configuration options via a file. [Ref: TG-14556]

  • IntelliJ Plugin: Cover now creates IntelliJ IDEA ‘run configurations’ with shorter names. [Ref: TG-14619]

Resolved Issues

  • Resolved an issue which provoked Cover to write nondeterministic tests involving Calendar.getInstance. [Ref: TG-14481]

  • IntelliJ Plugin: Resolved an issue which prevented Cover's 'write test' flask icon from writing tests for classes in default packages. [Ref: TG-14757]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, whilst using Cover's 'write test' flask icon on a just-created project, provoked a Reflection operation has failed error. [Ref: TG-14704]

  • IntelliJ Plugin: Resolved an issue which prevented IntelliJ IDEA 'run configurations' from being created when clicking 'Write Tests' on a class from IntelliJ IDEA's top navigation bar. [Ref: TG-14687]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, provoked an IntelliJ IDEA NullPointerExceptions error report. [Ref: TG-14633]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, whilst using Cover's 'write test' flask icon, provoked an IntelliJ IDEA IndexOutOfBoundsException error report. [Ref: TG-14628]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, whilst using Cover's 'write test' flask icon, provoked an IntelliJ IDEA InvalidPathExceptions error report. [Ref: TG-14627]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, provoked an IntelliJ IDEA Argument for @NotNull parameter 'module' of com/intellij/openapi/roots/ModuleRootManager.getInstance error report. [Ref: TG-14626]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, provoked an IntelliJ IDEA PsiInvalidElementAccessException error report. [Ref: TG-14487]

  • IntelliJ Plugin: Resolved an issue which, whilst writing tests for projects with # in their file path, provoked an IntelliJ IDEA URI has a fragment component error report. [Ref: TG-13913]

  • IntelliJ Plugin: Resolved an issue which, in some circumstances, provoked an IntelliJ IDEA Document is locked by write PSI operations error report. [Ref: TG-13148]

Known Issues

  • CLI: dcover clean --failing fails when used with a Gradle project. [Ref: TG-11707]

  • IntelliJ Plugin: Diffblue Cover was unable to create an index error may appear if switching project happens before Cover has finished indexing. [Ref: TG-13772]

Use Diffblue Cover on any CI platform to automatically update your unit tests and catch regressions for every commit - watch to learn more.

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