How to setup Karma runner code coverage?

问题

I am attempting to get Karma runner to generate cobertura formatted code coverage reports during a Jenkins build. I can get it to generate a coverage.xml file, but it does not actually have any coverage data. It appears (using LOG_DEBUG) that the coverage preprocessor is not running.

The relevant pieces from my karma.conf.js file are:

files = [
  JASMINE,
  JASMINE_ADAPTER,
  'app/components/angular/angular.js',
  'app/components/angular-mocks/angular-mocks.js',
  'tmp/scripts/**/*.js',
  'tmp/spec/**/*.js'
];

preprocessors = {
  'tmp/scripts/**/*.js': 'coverage'
};

// test results reporter to use
// possible values: 'dots', 'progress', 'junit'
reporters = ['dots', 'junit', 'coverage'];

junitReporter = {
  outputFile: 'test-results.xml'
};

coverageReporter = {
  type: 'cobertura',
  dir: 'coverage/',
  file: 'coverage.xml'
};

(The junit report is generating fine.)

回答1:

Apparently the karma code coverage documentation was more literal than I thought. Changing my preprocessors configuration to

preprocessors = {
  '**/tmp/scripts/**/*.js': 'coverage'
};

(notice the preceding **/) did the trick. I am not sure why the syntax is different for the files array and the preprocessors object ('tmp/scripts/**/*.js' vs. '**/tmp/scripts/**/*.js').

来源：https://stackoverflow.com/questions/15648775/how-to-setup-karma-runner-code-coverage