Lombok: Improve combability with cobertura

[halmafest]

I use lombok to generate a lot of code and I really like it!
To measure the code coverage we use cobertura

We like to use the cobertura option ignoreAnnotations. Basically the feature allows to disable code coverage checks of methods annotated with a defined annotation. Unfortunately the annotation added by lombok _javax.annotation.Generated_ does not work.

Reasons:

• as I understand cobertura works on class files
• _javax.annotation.Generated_ has a @Retention(value=SOURCE) definition (javadoc)
• means the annotation gets removed from the java compiler and is not visible during the code coverage check
• => each annotation having a @Retention(value=SOURCE) can not be used to exclude code.

Possible solutions:

• allow a user to define which annotation(s) are added to generated source
• add the already defined annotation _lombok.@Generated_ to generated source

[Maaartinus]

Another solution idea: At the end, for every @javax.annotation.Generated annotation, add @lombok.Generated. This could be pretty simple and could help other code generation tools.

[halmafest]

As a workaround I did a few modifications to the lombok code to write the lombok.Generated annotation in addition.

Changes:

• lombok.Generated is missing the constructor flag in the @Target
• when javax.annotation.Generated is written I added to write in addition lombok.Generated to the code

Result:

• + Code coverage reports looks nice now. Works together with cobertura
• + only few changes required
• - issues during delombok tests, annotation isn't known except you add lombok as dependency
• - forked library, need to rebuild for every new version of lombok I want to use

[rspilker]

It is possible to add an extra option to FormatPreferences either generate or not generate source code using the lombok.Generated annotation.

I think by default the lombok.Generated should not be generated in delomboked code.

Regarding the forked library: we do accept pull requests...

[dabraham02124]

Yes please, @halmafest. As the person who reported the dupe issue #1102, I'd love to see this pulled in to mainline lombok. Thank you very much.

[halmafest]

I will see if I can find some time the next weeks o make a clean pull request.
@rspilker, @all What is the preferred solution regarding FormatPreferences. I see two different options how to implement it:

• on/off switch to toggle generation of the lombock.Generated (same as for SuppressWarnings), default would be false (skip)
  
  
  
  • follows the current implementation
  
  
  • minimal changes required
  
  
• allow to define in the FormatPreferences a set of additional annotations to be added, defined using package and classname
  
  
  
  • more flexibility
  
  
  • added complexity to code
  
  
  • validation of the input might be tricky
  
  

[rspilker]

Thanks for offering to implement it. I prefer to have an on/off toggle in the FormatPreferences, defaulting to not generate it when delombokking.

[halmafest]

I started to implement this and I stuck a bit in the JavacHandlerUtil class. Maybe its only an understanding issue.

As I understand there are two ways to configure lombok.

• FormatPreferences
• LombokConfiguration/ConfigurationKeys

The FormatPreferences are checked first, ConfigurationKeys second.
Example:

public static void addGenerated(JCModifiers mods, JavacNode node, int pos, JCTree source, Context context) {
        if (!LombokOptionsFactory.getDelombokOptions(context).getFormatPreferences().generateGenerated()) return;

        if (!Boolean.FALSE.equals(node.getAst().readConfiguration(ConfigurationKeys.ADD_GENERATED_ANNOTATIONS))) {
            addAnnotation(mods, node, pos, source, context, "javax.annotation.Generated", node.getTreeMaker().Literal("lombok"));
        }
    }

This works fine as long the default value for an option in the FormatPreferences is set to true. For the new feature I like to set the default to false. This will lead to situation that for a normal javac run the FormatPreferences will be set to the defaults and the ConfigurationKeys are ignored.

I'm not sure how to solve this issue in the best way. Maybe there is a way to merge both configuration worlds.
In general I think the FormatPreferences class is located wrongly. As it is used in core, it should also be part of the core package otherwise you have a strong link to the delombok package. An alternative solution might be to remove all references to the FormatPreferences from the core classes and init LombokConfiguration values when running delombok.

[dabraham02124]

I was wondering if there was any motion on this. Or if there was any way that I could help with it. I'd love to have this, and I'm willing to at least try to help. Thank you very much.

[Gaibhne]

I forked Lombok, added a config key to specify the name of the annotation (like "lombok.generatedAnnotationName = com.whatever.test.LombokGenerated") which can then have a retain value of 'class', tested it with Cobertura and it worked perfectly fine. Since the ignore features in Jacoco are still in development I didn't bother testing them, but I see no reason it wouldn't work with that as well. I could make a PR, it's only like five lines of code changes, but I don't know how the Lombok team feels about adding config keys. @rspilker ?

[rspilker]

From now on, whenever @javax.annotation.Generated("lombok") was added, @lombok.Generated is also added.

To turn them both on or off, use the (original) configuration key lombok.addGeneratedAnnotation.

To override this general setting, use the keys lombok.addJavaxGeneratedAnnotation and lombok.addLombokGeneratedAnnotation.

For delombok you can turn them both off using the -f generated:skip command line parameter. This is only necessary if they were turned on in the configuration system in the first place.

[rspilker]

We've just created an edge release. Can someone try this out on cobertura and/or Jacoco?

[Gaibhne]

I can confirm it working with Cobertura and:

<build>
    <plugins>
        <!-- Code coverage plugin to produce test reports -->
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>cobertura-maven-plugin</artifactId>
            <version>2.7</version>
            <configuration>
                <instrumentation>
                    <ignoreMethodAnnotations>
                        <ignoreMethodAnnotation>lombok.Generated</ignoreMethodAnnotation>
                    </ignoreMethodAnnotations>
                </instrumentation>
            </configuration>
            <executions>
                <execution>
                    <goals>
                        <goal>clean</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

I have no Jacoco test environment set up since their filtering stuff is still in a dev branch as far as I can tell. Thanks for fixing/implementing this!

[seifertm]

This looks very promising! Thanks for your efforts.
Is there any preliminary date when this will make it into a release available on Maven central?

[rspilker]

Slight change of plans. @lombok.Generated needs to be explicitly turned on to cater for the scenario that the lombok version in the project is much older than the one used in Eclipse. This is the safest option.

The (original) configuration key lombok.addGeneratedAnnotation is now deprecated,
It is replaced by lombok.addJavaxGeneratedAnnotation

To generate @lombok.Generated use lombok.addLombokGeneratedAnnotation = true

We expect the release a new version of lombok within a few days.