refactor(Location): out of router and into platform/common

closes https://github.com/angular/angular/issues/4943

BREAKING CHANGE:

`Location` and other related providers have been moved out of `router` and into `platform/common`. `BrowserPlatformLocation` is not meant to be used directly however advanced configurations may use it via the following import change.

Before:

```
import {
  PlatformLocation,
  Location,
  LocationStrategy,
  HashLocationStrategy,
  PathLocationStrategy,
  APP_BASE_HREF}
from 'angular2/router';

import {BrowserPlatformLocation} from 'angular2/src/router/location/browser_platform_location';
```

After:

```
import {
  PlatformLocation,
  Location,
  LocationStrategy,
  HashLocationStrategy,
  PathLocationStrategy,
  APP_BASE_HREF}
from 'angular2/platform/common';

import {BrowserPlatformLocation} from 'angular2/src/platform/browser/location/browser_platform_location';
```

Closes #7962

modules/angular2/src/mock/location_mock.ts

@@ -1,7 +1,7 @@
 import {Injectable} from 'angular2/src/core/di';
 import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
 import {ListWrapper} from 'angular2/src/facade/collection';
-import {Location} from 'angular2/src/router/location/location';
+import {Location} from 'angular2/platform/common';
 
 /**
  * A spy for {@link Location} that allows tests to fire simulated location events.

modules/angular2/src/mock/mock_location_strategy.ts

@@ -1,6 +1,6 @@
 import {Injectable} from 'angular2/src/core/di';
 import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
-import {LocationStrategy} from 'angular2/src/router/location/location_strategy';
+import {LocationStrategy} from 'angular2/platform/common';
 
 
 /**

modules/angular2/src/platform/browser/location/browser_platform_location.ts

@@ -1,7 +1,6 @@
-import {Injectable} from 'angular2/core';
+import {Injectable} from 'angular2/src/core/di/decorators';
+import {UrlChangeListener, PlatformLocation} from './platform_location';
 import {History, Location} from 'angular2/src/facade/browser';
-import {UrlChangeListener} from './platform_location';
-import {PlatformLocation} from './platform_location';
 import {DOM} from 'angular2/src/platform/dom/dom_adapter';
 
 /**

modules/angular2/src/platform/browser/location/hash_location_strategy.ts

@@ -1,13 +1,8 @@
 import {Injectable, Inject, Optional} from 'angular2/core';
-import {
-  LocationStrategy,
-  joinWithSlash,
-  APP_BASE_HREF,
-  normalizeQueryParams
-} from './location_strategy';
-import {UrlChangeListener} from './platform_location';
+import {LocationStrategy, APP_BASE_HREF} from './location_strategy';
+import {Location} from './location';
+import {UrlChangeListener, PlatformLocation} from './platform_location';
 import {isPresent} from 'angular2/src/facade/lang';
-import {PlatformLocation} from './platform_location';
 
 /**
  * `HashLocationStrategy` is a {@link LocationStrategy} used to configure the
@@ -23,12 +18,14 @@ import {PlatformLocation} from './platform_location';
  * ```
  * import {Component, provide} from 'angular2/core';
  * import {
- *   ROUTER_DIRECTIVES,
- *   ROUTER_PROVIDERS,
- *   RouteConfig,
  *   Location,
  *   LocationStrategy,
  *   HashLocationStrategy
+ * } from 'angular2/platform/common';
+ * import {
+ *   ROUTER_DIRECTIVES,
+ *   ROUTER_PROVIDERS,
+ *   RouteConfig
  * } from 'angular2/router';
  *
  * @Component({directives: [ROUTER_DIRECTIVES]})
@@ -78,12 +75,12 @@ export class HashLocationStrategy extends LocationStrategy {
   }
 
   prepareExternalUrl(internal: string): string {
-    var url = joinWithSlash(this._baseHref, internal);
+    var url = Location.joinWithSlash(this._baseHref, internal);
     return url.length > 0 ? ('#' + url) : url;
   }
 
   pushState(state: any, title: string, path: string, queryParams: string) {
-    var url = this.prepareExternalUrl(path + normalizeQueryParams(queryParams));
+    var url = this.prepareExternalUrl(path + Location.normalizeQueryParams(queryParams));
     if (url.length == 0) {
       url = this._platformLocation.pathname;
     }
@@ -91,7 +88,7 @@ export class HashLocationStrategy extends LocationStrategy {
   }
 
   replaceState(state: any, title: string, path: string, queryParams: string) {
-    var url = this.prepareExternalUrl(path + normalizeQueryParams(queryParams));
+    var url = this.prepareExternalUrl(path + Location.normalizeQueryParams(queryParams));
     if (url.length == 0) {
       url = this._platformLocation.pathname;
     }

modules/angular2/src/platform/browser/location/location.ts

@@ -1,6 +1,6 @@
-import {LocationStrategy} from './location_strategy';
 import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
 import {Injectable, Inject} from 'angular2/core';
+import {LocationStrategy} from './location_strategy';
 
 /**
  * `Location` is a service that applications can use to interact with a browser's URL.
@@ -22,11 +22,11 @@ import {Injectable, Inject} from 'angular2/core';
  *
  * ```
  * import {Component} from 'angular2/core';
+ * import {Location} from 'angular2/platform/common';
  * import {
  *   ROUTER_DIRECTIVES,
  *   ROUTER_PROVIDERS,
- *   RouteConfig,
- *   Location
+ *   RouteConfig
  * } from 'angular2/router';
  *
  * @Component({directives: [ROUTER_DIRECTIVES]})
@@ -51,7 +51,7 @@ export class Location {
 
   constructor(public platformStrategy: LocationStrategy) {
     var browserBaseHref = this.platformStrategy.getBaseHref();
-    this._baseHref = stripTrailingSlash(stripIndexHtml(browserBaseHref));
+    this._baseHref = Location.stripTrailingSlash(_stripIndexHtml(browserBaseHref));
     this.platformStrategy.onPopState((ev) => {
       ObservableWrapper.callEmit(this._subject, {'url': this.path(), 'pop': true, 'type': ev.type});
     });
@@ -67,7 +67,7 @@ export class Location {
    * trailing slashes
    */
   normalize(url: string): string {
-    return stripTrailingSlash(_stripBaseHref(this._baseHref, stripIndexHtml(url)));
+    return Location.stripTrailingSlash(_stripBaseHref(this._baseHref, _stripIndexHtml(url)));
   }
 
   /**
@@ -117,6 +117,50 @@ export class Location {
             onReturn: () => void = null): Object {
     return ObservableWrapper.subscribe(this._subject, onNext, onThrow, onReturn);
   }
+
+  /**
+   * Given a string of url parameters, prepend with '?' if needed, otherwise return parameters as
+   * is.
+   */
+  public static normalizeQueryParams(params: string): string {
+    return (params.length > 0 && params.substring(0, 1) != '?') ? ('?' + params) : params;
+  }
+
+  /**
+   * Given 2 parts of a url, join them with a slash if needed.
+   */
+  public static joinWithSlash(start: string, end: string): string {
+    if (start.length == 0) {
+      return end;
+    }
+    if (end.length == 0) {
+      return start;
+    }
+    var slashes = 0;
+    if (start.endsWith('/')) {
+      slashes++;
+    }
+    if (end.startsWith('/')) {
+      slashes++;
+    }
+    if (slashes == 2) {
+      return start + end.substring(1);
+    }
+    if (slashes == 1) {
+      return start + end;
+    }
+    return start + '/' + end;
+  }
+
+  /**
+   * If url has a trailing slash, remove it, otherwise return url as is.
+   */
+  public static stripTrailingSlash(url: string): string {
+    if (/\/$/g.test(url)) {
+      url = url.substring(0, url.length - 1);
+    }
+    return url;
+  }
 }
 
 function _stripBaseHref(baseHref: string, url: string): string {
@@ -126,17 +170,10 @@ function _stripBaseHref(baseHref: string, url: string): string {
   return url;
 }
 
-function stripIndexHtml(url: string): string {
+function _stripIndexHtml(url: string): string {
   if (/\/index.html$/g.test(url)) {
     // '/index.html'.length == 11
     return url.substring(0, url.length - 11);
   }
   return url;
 }
-
-function stripTrailingSlash(url: string): string {
-  if (/\/$/g.test(url)) {
-    url = url.substring(0, url.length - 1);
-  }
-  return url;
-}

modules/angular2/src/platform/browser/location/location_strategy.ts

@@ -43,6 +43,7 @@ export abstract class LocationStrategy {
  * ```
  * import {Component} from 'angular2/core';
  * import {ROUTER_DIRECTIVES, ROUTER_PROVIDERS, RouteConfig} from 'angular2/router';
+ * import {APP_BASE_HREF} from 'angular2/platform/common';
  *
  * @Component({directives: [ROUTER_DIRECTIVES]})
  * @RouteConfig([
@@ -59,30 +60,3 @@ export abstract class LocationStrategy {
  * ```
  */
 export const APP_BASE_HREF: OpaqueToken = CONST_EXPR(new OpaqueToken('appBaseHref'));
-
-export function normalizeQueryParams(params: string): string {
-  return (params.length > 0 && params.substring(0, 1) != '?') ? ('?' + params) : params;
-}
-
-export function joinWithSlash(start: string, end: string): string {
-  if (start.length == 0) {
-    return end;
-  }
-  if (end.length == 0) {
-    return start;
-  }
-  var slashes = 0;
-  if (start.endsWith('/')) {
-    slashes++;
-  }
-  if (end.startsWith('/')) {
-    slashes++;
-  }
-  if (slashes == 2) {
-    return start + end.substring(1);
-  }
-  if (slashes == 1) {
-    return start + end;
-  }
-  return start + '/' + end;
-}

modules/angular2/src/platform/browser/location/path_location_strategy.ts

@@ -1,13 +1,9 @@
 import {Injectable, Inject, Optional} from 'angular2/core';
 import {isBlank} from 'angular2/src/facade/lang';
 import {BaseException} from 'angular2/src/facade/exceptions';
-import {
-  LocationStrategy,
-  APP_BASE_HREF,
-  normalizeQueryParams,
-  joinWithSlash
-} from './location_strategy';
 import {PlatformLocation, UrlChangeListener} from './platform_location';
+import {LocationStrategy, APP_BASE_HREF} from './location_strategy';
+import {Location} from './location';
 
 /**
  * `PathLocationStrategy` is a {@link LocationStrategy} used to configure the
@@ -30,12 +26,15 @@ import {PlatformLocation, UrlChangeListener} from './platform_location';
  *
  * ```
  * import {Component, provide} from 'angular2/core';
+ * import {bootstrap} from 'angular2/platform/browser';
  * import {
+ *   Location,
  *   APP_BASE_HREF
+ * } from 'angular2/platform/common';
+ * import {
  *   ROUTER_DIRECTIVES,
  *   ROUTER_PROVIDERS,
- *   RouteConfig,
- *   Location
+ *   RouteConfig
  * } from 'angular2/router';
  *
  * @Component({directives: [ROUTER_DIRECTIVES]})
@@ -81,19 +80,22 @@ export class PathLocationStrategy extends LocationStrategy {
 
   getBaseHref(): string { return this._baseHref; }
 
-  prepareExternalUrl(internal: string): string { return joinWithSlash(this._baseHref, internal); }
+  prepareExternalUrl(internal: string): string {
+    return Location.joinWithSlash(this._baseHref, internal);
+  }
 
   path(): string {
-    return this._platformLocation.pathname + normalizeQueryParams(this._platformLocation.search);
+    return this._platformLocation.pathname +
+           Location.normalizeQueryParams(this._platformLocation.search);
   }
 
   pushState(state: any, title: string, url: string, queryParams: string) {
-    var externalUrl = this.prepareExternalUrl(url + normalizeQueryParams(queryParams));
+    var externalUrl = this.prepareExternalUrl(url + Location.normalizeQueryParams(queryParams));
     this._platformLocation.pushState(state, title, externalUrl);
   }
 
   replaceState(state: any, title: string, url: string, queryParams: string) {
-    var externalUrl = this.prepareExternalUrl(url + normalizeQueryParams(queryParams));
+    var externalUrl = this.prepareExternalUrl(url + Location.normalizeQueryParams(queryParams));
     this._platformLocation.replaceState(state, title, externalUrl);
   }
 

modules/angular2/src/platform/location.ts

@@ -0,0 +1,5 @@
+export * from './browser/location/platform_location';
+export * from './browser/location/location_strategy';
+export * from './browser/location/hash_location_strategy';
+export * from './browser/location/path_location_strategy';
+export * from './browser/location/location';

modules/angular2/src/platform/worker_render_common.ts

@@ -36,7 +36,6 @@ import {BrowserDomAdapter} from './browser/browser_adapter';
 import {wtfInit} from 'angular2/src/core/profile/wtf_init';
 import {MessageBasedRenderer} from 'angular2/src/web_workers/ui/renderer';
 import {MessageBasedXHRImpl} from 'angular2/src/web_workers/ui/xhr_impl';
-import {BrowserPlatformLocation} from 'angular2/src/router/location/browser_platform_location';
 import {
   ServiceMessageBrokerFactory,
   ServiceMessageBrokerFactory_
@@ -45,6 +44,9 @@ import {
   ClientMessageBrokerFactory,
   ClientMessageBrokerFactory_
 } from 'angular2/src/web_workers/shared/client_message_broker';
+import {
+  BrowserPlatformLocation
+} from 'angular2/src/platform/browser/location/browser_platform_location';
 import {Serializer} from 'angular2/src/web_workers/shared/serializer';
 import {ON_WEB_WORKER} from 'angular2/src/web_workers/shared/api';
 import {RenderStore} from 'angular2/src/web_workers/shared/render_store';

modules/angular2/src/router/directives/router_link.ts

@@ -1,8 +1,8 @@
 import {Directive} from 'angular2/core';
+import {Location} from 'angular2/platform/common';
 import {isString} from 'angular2/src/facade/lang';
 
 import {Router} from '../router';
-import {Location} from '../location/location';
 import {Instruction} from '../instruction';
 
 /**

modules/angular2/src/router/router.ts

@@ -2,6 +2,7 @@ import {PromiseWrapper, EventEmitter, ObservableWrapper} from 'angular2/src/faca
 import {Map, StringMapWrapper, MapWrapper, ListWrapper} from 'angular2/src/facade/collection';
 import {isBlank, isString, isPresent, Type, isArray} from 'angular2/src/facade/lang';
 import {BaseException, WrappedException} from 'angular2/src/facade/exceptions';
+import {Location} from 'angular2/platform/common';
 import {Inject, Injectable} from 'angular2/core';
 
 import {RouteRegistry, ROUTER_PRIMARY_COMPONENT} from './route_registry';
@@ -10,7 +11,6 @@ import {
   Instruction,
 } from './instruction';
 import {RouterOutlet} from './directives/router_outlet';
-import {Location} from './location/location';
 import {getCanActivateHook} from './lifecycle/route_lifecycle_reflector';
 import {RouteDefinition} from './route_config/route_config_impl';
 

modules/angular2/src/router/router_providers.ts

@@ -1,8 +1,10 @@
 import {ROUTER_PROVIDERS_COMMON} from './router_providers_common';
 import {Provider} from 'angular2/core';
+import {
+  BrowserPlatformLocation
+} from 'angular2/src/platform/browser/location/browser_platform_location';
+import {PlatformLocation} from 'angular2/platform/common';
 import {CONST_EXPR} from 'angular2/src/facade/lang';
-import {BrowserPlatformLocation} from './location/browser_platform_location';
-import {PlatformLocation} from './location/platform_location';
 
 /**
  * A list of {@link Provider}s. To use the router, you must add this to your application.

modules/angular2/src/router/router_providers_common.ts

@@ -1,8 +1,6 @@
-import {LocationStrategy} from 'angular2/src/router/location/location_strategy';
-import {PathLocationStrategy} from 'angular2/src/router/location/path_location_strategy';
+import {LocationStrategy, PathLocationStrategy, Location} from 'angular2/platform/common';
 import {Router, RootRouter} from 'angular2/src/router/router';
 import {RouteRegistry, ROUTER_PRIMARY_COMPONENT} from 'angular2/src/router/route_registry';
-import {Location} from 'angular2/src/router/location/location';
 import {CONST_EXPR, Type} from 'angular2/src/facade/lang';
 import {ApplicationRef, OpaqueToken, Provider} from 'angular2/core';
 import {BaseException} from 'angular2/src/facade/exceptions';

modules/angular2/src/web_workers/ui/platform_location.ts

@@ -1,4 +1,7 @@
-import {BrowserPlatformLocation} from 'angular2/src/router/location/browser_platform_location';
+import {
+  BrowserPlatformLocation
+} from 'angular2/src/platform/browser/location/browser_platform_location';
+import {UrlChangeListener} from 'angular2/platform/common';
 import {Injectable} from 'angular2/src/core/di';
 import {ROUTER_CHANNEL} from 'angular2/src/web_workers/shared/messaging_api';
 import {
@@ -10,7 +13,6 @@ import {bind} from './bind';
 import {LocationType} from 'angular2/src/web_workers/shared/serialized_types';
 import {MessageBus} from 'angular2/src/web_workers/shared/message_bus';
 import {EventEmitter, ObservableWrapper, PromiseWrapper} from 'angular2/src/facade/async';
-import {UrlChangeListener} from 'angular2/src/router/location/platform_location';
 
 @Injectable()
 export class MessageBasedPlatformLocation {

modules/angular2/src/web_workers/ui/router_providers.ts

@@ -1,6 +1,8 @@
 import {MessageBasedPlatformLocation} from './platform_location';
 import {CONST_EXPR} from 'angular2/src/facade/lang';
-import {BrowserPlatformLocation} from 'angular2/src/router/location/browser_platform_location';
+import {
+  BrowserPlatformLocation
+} from 'angular2/src/platform/browser/location/browser_platform_location';
 import {APP_INITIALIZER, Provider, Injector, NgZone} from 'angular2/core';
 
 export const WORKER_RENDER_ROUTER = CONST_EXPR([

modules/angular2/src/web_workers/worker/platform_location.ts

@@ -1,15 +1,11 @@
 import {Injectable} from 'angular2/src/core/di';
-import {
-  PlatformLocation,
-  UrlChangeEvent,
-  UrlChangeListener
-} from 'angular2/src/router/location/platform_location';
 import {
   FnArg,
   UiArguments,
   ClientMessageBroker,
   ClientMessageBrokerFactory
 } from 'angular2/src/web_workers/shared/client_message_broker';
+import {PlatformLocation, UrlChangeEvent, UrlChangeListener} from 'angular2/platform/common';
 import {ROUTER_CHANNEL} from 'angular2/src/web_workers/shared/messaging_api';
 import {LocationType} from 'angular2/src/web_workers/shared/serialized_types';
 import {PromiseWrapper, EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';

modules/angular2/src/web_workers/worker/router_providers.ts

@@ -1,5 +1,5 @@
 import {ApplicationRef, Provider, NgZone, APP_INITIALIZER} from 'angular2/core';
-import {PlatformLocation} from 'angular2/src/router/location/platform_location';
+import {PlatformLocation} from 'angular2/platform/common';
 import {WebWorkerPlatformLocation} from './platform_location';
 import {ROUTER_PROVIDERS_COMMON} from 'angular2/src/router/router_providers_common';