Function mergeHeaders

test/angular/1.4/angular.js:10626–10649

(config)

      }

      function mergeHeaders(config) {
        var defHeaders = defaults.headers,
            reqHeaders = extend({}, config.headers),
            defHeaderName, lowercaseDefHeaderName, reqHeaderName;

        defHeaders = extend({}, defHeaders.common, defHeaders[lowercase(config.method)]);

        // using for-in instead of forEach to avoid unecessary iteration after header has been found
        defaultHeadersIteration:
        for (defHeaderName in defHeaders) {
          lowercaseDefHeaderName = lowercase(defHeaderName);

          for (reqHeaderName in reqHeaders) {
            if (lowercase(reqHeaderName) === lowercaseDefHeaderName) {
              continue defaultHeadersIteration;
            }
          }

          reqHeaders[defHeaderName] = defHeaders[defHeaderName];
        }

        // execute if header value is a function for merged headers
        return executeHeaderFns(reqHeaders, shallowCopy(config));
      }
    }

    $http.pendingRequests = [];