Module io.github.ascopes.jct
Package io.github.ascopes.jct.compilers

Interface JctCompilerConfigurer<E extends Exception>

Type Parameters:
E - the exception that may be thrown by the configurer.
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@API(since="0.0.1", status=STABLE) @FunctionalInterface public interface JctCompilerConfigurer<E extends Exception>
Function representing a configuration operation that can be applied to a compiler.

This can allow encapsulating common configuration logic across tests into a single place.

Implementations of this interface should declare the exception type that the implementation can throw when invoked. If this is not a checked exception, or no case exists where an exception could be thrown, then this can be set to RuntimeException.

The following demonstrates an example usage of this interface. The implementation configures a specific annotation processor and sets an annotation processor flag. 


 class MyAnnotationProcessorConfigurer implements JctCompilerConfigurer<RuntimeException> {
    @Override
    public void configure(JctCompiler compiler) {
      compiler
          .addAnnotationProcessors(new MyAnnotationProcessor())
          .addAnnotationProcessorOptions("MyAnnotationProcessor.debug=true");
    }
 }

...tests can then make use of this configurer directly: 


    @Test
    void theCompilationSucceedsAsExpected() {
      try (var workspace = Workspaces.newWorkspace()) {
        // Given
        ...

        var compiler = JctCompilers
            .newPlatformCompiler()
            .release(17)
            .configure(new MyAnnotationProcessorConfigurer());

        // When
        var compilation = compiler.compile(workspace);

        // Then
        ...
      }
    }

Since this is a functional interface, configurers can be lambda expressions, anonymous objects, or method references. 


   compiler
      .configure(c -> c.release(11))
      .configure(this::configureFailures);

The JUnit support allows for specifying these configurers in an annotation instead. This will apply the configurer before passing it to the test as a parameter: 


   @JavacCompilersTest(configurers = {MyAnnotationProcessorConfigurer.class})
   void theCompilationSucceedsAsExpected(JctCompiler compiler) {
     // ...
   }

Note that in this case, the configurer must be an outer class or a static nested class rather than a Lambda expression, anonymous class, class instance, or nested class. It must also have a single public no-arguments constructor in order to be accessible.

Since:
0.0.1
Author:
Ashley Scopes