refactor(i18n): I18nPipe uses NgLocalization (#9313)

and some refactoring

modules/@angular/common/src/directives.ts

@@ -15,7 +15,7 @@ export {CORE_DIRECTIVES} from './directives/core_directives';
 export {NgClass} from './directives/ng_class';
 export {NgFor} from './directives/ng_for';
 export {NgIf} from './directives/ng_if';
-export {NgLocalization, NgPlural, NgPluralCase} from './directives/ng_plural';
+export {NgPlural, NgPluralCase} from './directives/ng_plural';
 export {NgStyle} from './directives/ng_style';
 export {NgSwitch, NgSwitchCase, NgSwitchDefault} from './directives/ng_switch';
 export {NgTemplateOutlet} from './directives/ng_template_outlet';

modules/@angular/common/src/directives/ng_plural.ts

@@ -7,19 +7,10 @@
  */
 
 import {AfterContentInit, Attribute, ContentChildren, Directive, Input, QueryList, TemplateRef, ViewContainerRef} from '@angular/core';
-
-import {Map} from '../facade/collection';
-import {NumberWrapper, isPresent} from '../facade/lang';
-
+import {isPresent} from '../facade/lang';
+import {NgLocalization, getPluralCategory} from '../localization';
 import {SwitchView} from './ng_switch';
 
-const _CATEGORY_DEFAULT = 'other';
-
-/**
- * @experimental
- */
-export abstract class NgLocalization { abstract getPluralCategory(value: any): string; }
-
 /**
  * `ngPlural` is an i18n directive that displays DOM sub-trees that match the switch expression
  * value, or failing that, DOM sub-trees that match the switch expression's pluralization category.
@@ -35,9 +26,6 @@ export abstract class NgLocalization { abstract getPluralCategory(value: any): s
  * value matches aren't found and the value maps to its category using the `getPluralCategory`
  * function provided.
  *
- * If no matching views are found for a switch expression, inner elements marked
- * `[ngPluralCase]="other"` will be displayed.
- *
  * ```typescript
  * class MyLocalization extends NgLocalization {
  *    getPluralCategory(value: any) {
@@ -88,7 +76,6 @@ export class NgPluralCase {
   }
 }
 
-
 /**
  * @experimental
  */
@@ -96,7 +83,7 @@ export class NgPluralCase {
 export class NgPlural implements AfterContentInit {
   private _switchValue: number;
   private _activeView: SwitchView;
-  private _caseViews = new Map<any, SwitchView>();
+  private _caseViews: {[k: string]: SwitchView} = {};
   @ContentChildren(NgPluralCase) cases: QueryList<NgPluralCase> = null;
 
   constructor(private _localization: NgLocalization) {}
@@ -109,7 +96,7 @@ export class NgPlural implements AfterContentInit {
 
   ngAfterContentInit() {
     this.cases.forEach((pluralCase: NgPluralCase): void => {
-      this._caseViews.set(this._formatValue(pluralCase), pluralCase._view);
+      this._caseViews[pluralCase.value] = pluralCase._view;
     });
     this._updateView();
   }
@@ -118,10 +105,9 @@ export class NgPlural implements AfterContentInit {
   _updateView(): void {
     this._clearViews();
 
-    var view: SwitchView = this._caseViews.get(this._switchValue);
-    if (!isPresent(view)) view = this._getCategoryView(this._switchValue);
-
-    this._activateView(view);
+    var key = getPluralCategory(
+        this._switchValue, Object.getOwnPropertyNames(this._caseViews), this._localization);
+    this._activateView(this._caseViews[key]);
   }
 
   /** @internal */
@@ -135,22 +121,4 @@ export class NgPlural implements AfterContentInit {
     this._activeView = view;
     this._activeView.create();
   }
-
-  /** @internal */
-  _getCategoryView(value: number): SwitchView {
-    var category: string = this._localization.getPluralCategory(value);
-    var categoryView: SwitchView = this._caseViews.get(category);
-    return isPresent(categoryView) ? categoryView : this._caseViews.get(_CATEGORY_DEFAULT);
-  }
-
-  /** @internal */
-  _isValueView(pluralCase: NgPluralCase): boolean { return pluralCase.value[0] === '='; }
-
-  /** @internal */
-  _formatValue(pluralCase: NgPluralCase): any {
-    return this._isValueView(pluralCase) ? this._stripValue(pluralCase.value) : pluralCase.value;
-  }
-
-  /** @internal */
-  _stripValue(value: string): number { return NumberWrapper.parseInt(value.substring(1), 10); }
 }

modules/@angular/common/src/localization.ts

@@ -0,0 +1,18 @@
+/**
+ * @experimental
+ */
+export abstract class NgLocalization { abstract getPluralCategory(value: any): string; }
+
+/**
+ * Returns the plural category for a given value.
+ * - "=value" when the case exists,
+ * - the plural category otherwise
+ *
+ * @internal
+ */
+export function getPluralCategory(
+    value: number, cases: string[], ngLocalization: NgLocalization): string {
+  const nbCase = `=${value}`;
+
+  return cases.indexOf(nbCase) > -1 ? nbCase : ngLocalization.getPluralCategory(value);
+}

modules/@angular/common/src/pipes/i18n_plural_pipe.ts

@@ -7,22 +7,21 @@
  */
 
 import {Pipe, PipeTransform} from '@angular/core';
-import {StringWrapper, isPresent, isStringMap} from '../facade/lang';
+import {StringWrapper, isBlank, isStringMap} from '../facade/lang';
+import {NgLocalization, getPluralCategory} from '../localization';
 import {InvalidPipeArgumentException} from './invalid_pipe_argument_exception';
 
 const _INTERPOLATION_REGEXP: RegExp = /#/g;
 
 /**
- *
  *  Maps a value to a string that pluralizes the value properly.
  *
  *  ## Usage
  *
  *  expression | i18nPlural:mapping
  *
- *  where `expression` is a number and `mapping` is an object that indicates the proper text for
- *  when the `expression` evaluates to 0, 1, or some other number.  You can interpolate the actual
- *  value into the text using the `#` sign.
+ *  where `expression` is a number and `mapping` is an object that mimics the ICU format,
+ *  see http://userguide.icu-project.org/formatparse/messages
  *
  *  ## Example
  *
@@ -33,7 +32,7 @@ const _INTERPOLATION_REGEXP: RegExp = /#/g;
  *
  *  class MyApp {
  *    messages: any[];
- *    messageMapping: any = {
+ *    messageMapping: {[k:string]: string} = {
  *      '=0': 'No messages.',
  *      '=1': 'One message.',
  *      'other': '# messages.'
@@ -46,17 +45,17 @@ const _INTERPOLATION_REGEXP: RegExp = /#/g;
  */
 @Pipe({name: 'i18nPlural', pure: true})
 export class I18nPluralPipe implements PipeTransform {
+  constructor(private _localization: NgLocalization) {}
+
   transform(value: number, pluralMap: {[count: string]: string}): string {
-    var key: string;
-    var valueStr: string;
+    if (isBlank(value)) return '';
 
     if (!isStringMap(pluralMap)) {
       throw new InvalidPipeArgumentException(I18nPluralPipe, pluralMap);
     }
 
-    key = value === 0 || value === 1 ? `=${value}` : 'other';
-    valueStr = isPresent(value) ? value.toString() : '';
+    const key = getPluralCategory(value, Object.getOwnPropertyNames(pluralMap), this._localization);
 
-    return StringWrapper.replaceAll(pluralMap[key], _INTERPOLATION_REGEXP, valueStr);
+    return StringWrapper.replaceAll(pluralMap[key], _INTERPOLATION_REGEXP, value.toString());
   }
 }

modules/@angular/common/src/pipes/i18n_select_pipe.ts

@@ -7,11 +7,9 @@
  */
 
 import {Pipe, PipeTransform} from '@angular/core';
-import {StringMapWrapper} from '../facade/collection';
-import {isStringMap} from '../facade/lang';
+import {isBlank, isStringMap} from '../facade/lang';
 import {InvalidPipeArgumentException} from './invalid_pipe_argument_exception';
 
-
 /**
  *
  *  Generic selector that displays the string that matches the current value.
@@ -46,10 +44,12 @@ import {InvalidPipeArgumentException} from './invalid_pipe_argument_exception';
 @Pipe({name: 'i18nSelect', pure: true})
 export class I18nSelectPipe implements PipeTransform {
   transform(value: string, mapping: {[key: string]: string}): string {
+    if (isBlank(value)) return '';
+
     if (!isStringMap(mapping)) {
       throw new InvalidPipeArgumentException(I18nSelectPipe, mapping);
     }
 
-    return StringMapWrapper.contains(mapping, value) ? mapping[value] : mapping['other'];
+    return mapping.hasOwnProperty(value) ? mapping[value] : '';
   }
 }