Approval Test Button

Displays a toolbar button on the JUnit results view to accept the results by overwriting the file containing the expected output.
This fits the approval test methodology. The logic works by default with the approvaltests library, which produces an AssertionError with the 'received' and 'approved' file path.
But it also works with other test failures, where the error messages clearly reference the output file.
It's worth using a custom JUnit reporter with the approval tests to leverage the built-in support for comparison view and avoid popping up external diff tools.
 

public enum CustomJunit4Reporter implements ApprovalFailureReporter
{
    INSTANCE;
    @Override
    public boolean report(String received, String approved) {
        String actual = FileUtils.readFile(received);
		File approvedFile = new File(approved);
		String expected = approvedFile.canRead() ? FileUtils.readFile(approved) : "";
		Assert.assertEquals("Actual result does not match content of " + approvedFile.getAbsolutePath(), expected, actual);
		return true;
	}
}

Then use it in the tests like

Approvals.verify(actual, new Options(CustomJunit4Reporter.INSTANCE));

The plugin supports the default verify failures, assuming the default file names.

Shortcuts make it really easy to open the diff view (Ctrl+D) or view the test resource (Ctrl+V) if needed.