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test/specs/core/mergeConfig.spec.js
expect(merged).not.toBe(defaults);
    expect(merged.headers).not.toBe(defaults.headers);
  });
  it('should allow setting request options', function() {
    var config = {
      url: '__sample url__',
      method: '__sample method__',
      params: '__sample params__',
      data: { foo: true }
    };
    var merged = mergeConfig(defaults, config);
    expect(merged.url).toEqual(config.url);
    expect(merged.method).toEqual(config.method);
    expect(merged.params).toEqual(config.params);
    expect(merged.data).toEqual(config.data);
  });
  it('should not inherit request options', function() {
    var localDefaults = {
      method: '__sample method__',
      data: { foo: true }
    };
    var merged = mergeConfig(localDefaults, {});
    expect(merged.method).toEqual(undefined);
    expect(merged.data).toEqual(undefined);
  });
  ['auth', 'headers', 'params', 'proxy'].forEach(function(key) {
    it('should set new config for' + key + ' without default', function() {
      var a = {}, b = {}, c = {}
      a[key] = undefined
      b[key] = { user: 'foo', pass: 'test' }