karma-jasmine-diff-reporter/index.js

Diff and pretty print for failed tests

'use strict';

var path = require('path');

var karma = require('karma');
var jasmine = require('jasmine-core');

var createColorHighlighter = require('./src/color-highlighter');
var format = require('./src/format');
var defaults = require('./src/utils/object').defaults;

var karmaMajorVersion = Number(karma.VERSION.split('.')[0]);
var jasmineMajorVersion = Number(jasmine.version().split('.')[0]);

// https://github.com/mradionov/karma-jasmine-diff-reporter/issues/63
function maybeLogDeprecationWarning(log) {
  if (jasmineMajorVersion >= 4) {
    log.warn('Plugin "karma-jasmine-diff-reporter" does not support Jasmine 4+. Consider removing it from your configuration.');
    return true;
  }
  return false;
}

function jasmineDiffFramework(config, logger) {
  var log = logger.create('jasmine-diff');

  if (maybeLogDeprecationWarning(log)) {
    return;
  }

  // karma-jasmine uses adapter to work with Jasmine
  // Use it to include custom patch for Jasmine right before adapter starts

  var jasminePath = path.dirname(require.resolve('jasmine-core'));
  var coreFile = '/jasmine-core/jasmine.js';
  var jasmineCorePath = jasminePath + coreFile;

  var index = -1;
  for (var i = 0, l = config.files.length; i < l; i++) {
    if (config.files[i].pattern === jasmineCorePath) {
      index = i;
      break;
    }
  }

  if (index === -1) {
    log.warn('File "%s" not found in module "jasmine-core".', coreFile);
    log.warn('You may be using a not supported Jasmine version.');
    log.warn('Pretty print option will not be available');
    return;
  }

  // Inject patch file for pretty print

  var ppPatchPath = path.join(__dirname, 'src', 'karma-jasmine', 'pp-patch.js');

  config.files.splice(index + 2, 0, {
    pattern: ppPatchPath,
    included: true,
    served: true,
    watched: false
  });

  // Inject patch to bring back legacy diffs for objects after Jasmine 2.6

  var utilPatchPath = path.join(__dirname, 'src', 'karma-jasmine', 'util-patch.js');

  config.files.splice(index + 3, 0, {
    pattern: utilPatchPath,
    included: true,
    served: true,
    watched: false
  });
}

function jasmineDiffReporter(baseReporterDecorator, config, logger) {
  var self = this;

  var log = logger.create('jasmine-diff');

  if (maybeLogDeprecationWarning(log)) {
    return;
  }

  // Extend Karma Base reporter
  baseReporterDecorator(self);

  var reporterConfig = defaults(config.jasmineDiffReporter || {}, {
    matchers: {},
    color: {},
    pretty: false,
    multiline: false,
    verbose: true
  });

  reporterConfig.color.enabled = !!config.colors;

  // Create formatter responsible for highlighting message fragments
  // and pass it to diff function as a dep to be able to replace it in tests
  var colorFormatter = createColorHighlighter(reporterConfig.color);

  // Check if reporter is last in the list of config reporters
  var reporterName = 'jasmine-diff';
  var hasTrailingReporters = config.reporters.slice(-1).pop() !== reporterName;

  // Override Base reporter method
  // Replace original message with highlighted one

  var originalSpecFailure = self.specFailure;

  self.specFailure = function (browser, result) {
    result.log = result.log.map(function (message) {
      return format(message, colorFormatter, reporterConfig);
    });

    // If reporter is last in the list of reporters from config
    // then invoke Karma's Base reporter. Basically this reporter
    // just changes the message, but does not output info by itself,
    // so one could use any reporter and still have highlighted diff.
    if (!hasTrailingReporters) {
      originalSpecFailure.call(self, browser, result);
    }
  };

  // In case, when multiple reporters are used in conjunction
  // with karma-jasmine-diff-reporter, they both will show repetitive log
  // messages when displaying everything that supposed to write to terminal.
  // So just suppress any logs from karma-jasmine-diff-reporter, because
  // it is an utility reporter by doing nothing on browser log,
  // unless it's alone in the "reporters" option and base reporter is used.
  if (hasTrailingReporters) {
    self.writeCommonMsg = function () {};
  }

  // Secretly inject a framework to be able to patch Jasmine
  // Frameworks are included earlier in Karma workflow so it is possible
  // to inject some script on a test page.

  // Framework injection is different in 0.x and 1.x karma, manually injecting
  // a framework won't work in 1.x, but files injection does work from inside
  // of the reporter in 1.x, so call it manually for 1.x versions
  if (karmaMajorVersion < 1) {
    config.frameworks.push('jasmine-diff');
  } else {
    jasmineDiffFramework(config, logger);
  }
}


jasmineDiffReporter.$inject = ['baseReporterDecorator', 'config', 'logger'];
jasmineDiffFramework.$inject = ['config', 'logger'];

var modules = {
  'reporter:jasmine-diff': ['type', jasmineDiffReporter]
};

// Framework insertion is different in 0.x and 1.x karma, manually injecting
// a framework won't work in 1.x, but files injection does work from inside
// of the reporter
if (karmaMajorVersion < 1) {
  modules['framework:jasmine-diff'] = ['factory', jasmineDiffFramework];
}

module.exports = modules;