allow coverage instrumentation of multiple files

[bjouhier]

This PR is a quick hack to enable code coverage on multiple files. It allows you to set the coverage option to:

• a string, in which case all source files with an absolute path matching the string will be included in the coverage report.
• a regexp, in which case all source files with a path that matches the regexp will be included.
• true, in which case only the file specified with the code option will be included in the coverage report.

[fyockm]

Hi @bjouhier!

Instead of overloading the coverage option as a string or Regex, do you think it would make more sense to add a new key for files?
While your proposed change provides flexiblility for specifying the coverage files, it wouldn't allow setting the other coverage options, like dir or reporters.

lib/coverage.js

options = {
    dir: 'coverage',
    reporters: ['lcov', 'json'],
    files: null
};

Not quite as clean, but then the matcher function could be something like this:

matcher = function(file) {
    if (options.coverage.files) {
        if (typeof options.coverage.files === 'string') return file.indexOf(options.coverage) === 0;
        else if (options.coverage.files instanceof RegExp) return options.coverage.test(file);
    }
    return file === options.code.path;
}

An even better solution might utilize pattern globbing, but perhaps as a future enhancement.

[kof]

I think instead of string, we should use an array here, otherwise its fine ...

[bjouhier]

@fyockm Hi Drew!!!

That's a good point. I've followed your suggestion to use options.coverage.files and I've also enabled arrays. So you can specify an array of files or regexps.

[kof]

merged

[bjouhier]

Thanks @kof

[bjouhier]

@kof @fyockm I just tried the regexp feature and found out that it is completely broken. Problem is that options are serialized between testrunner and child and JSON does not like regexps!

[kof]

thats true, do we really need regexp there?

[kof]

Can you add some tests?

[bjouhier]

I can manage without regexps. Looked like a cool and easy-to-implement feature but it's only cool.

I'll remove regexps and add tests but I'll do it a bit later.

[kof]

👍