From d5a12d59ca33ecd00223e644e17fe85f9aa984b9 Mon Sep 17 00:00:00 2001
From: Marc Laval <mlaval@amadeus.com>
Date: Wed, 17 Dec 2014 10:01:08 +0100
Subject: [PATCH] feat(ng-if): an implementation of ng-if

Closes #317
---
 modules/directives/src/ng_if.js       |  30 ++++
 modules/directives/test/ng_if_spec.js | 217 ++++++++++++++++++++++++++
 2 files changed, 247 insertions(+)
 create mode 100644 modules/directives/src/ng_if.js
 create mode 100644 modules/directives/test/ng_if_spec.js

diff --git a/modules/directives/src/ng_if.js b/modules/directives/src/ng_if.js
new file mode 100644
index 0000000000..8a24bd4060
--- /dev/null
+++ b/modules/directives/src/ng_if.js
@@ -0,0 +1,30 @@
+import {Template} from 'core/annotations/annotations';
+import {OnChange} from 'core/compiler/interfaces';
+import {ViewPort} from 'core/compiler/viewport';
+import {isBlank} from 'facade/lang';
+
+@Template({
+  selector: '[ng-if]',
+  bind: {
+    'ng-if': 'condition'
+  }
+})
+export class NgIf {
+  viewPort: ViewPort;
+  prevCondition: boolean;
+
+  constructor(viewPort: ViewPort) {
+    this.viewPort = viewPort;
+    this.prevCondition = null;
+  }
+
+  set condition(newCondition) {
+    if (newCondition && (isBlank(this.prevCondition) || !this.prevCondition)) {
+      this.prevCondition = true;
+      this.viewPort.create();
+    } else if (!newCondition && (isBlank(this.prevCondition) || this.prevCondition)) {
+      this.prevCondition = false;
+      this.viewPort.clear();
+    }
+  }
+}
diff --git a/modules/directives/test/ng_if_spec.js b/modules/directives/test/ng_if_spec.js
new file mode 100644
index 0000000000..e6324f0a3c
--- /dev/null
+++ b/modules/directives/test/ng_if_spec.js
@@ -0,0 +1,217 @@
+import {describe, xit, it, expect, beforeEach, ddescribe, iit, IS_DARTIUM} from 'test_lib/test_lib';
+
+import {DOM} from 'facade/dom';
+
+import {Injector} from 'di/di';
+import {Lexer, Parser, ChangeDetector} from 'change_detection/change_detection';
+
+import {Compiler, CompilerCache} from 'core/compiler/compiler';
+import {DirectiveMetadataReader} from 'core/compiler/directive_metadata_reader';
+
+import {Component} from 'core/annotations/annotations';
+import {TemplateConfig} from 'core/annotations/template_config';
+
+import {NgIf} from 'directives/ng_if';
+
+export function main() {
+  describe('ng-if', () => {
+    var view, cd, compiler, component;
+    beforeEach(() => {
+      compiler = new Compiler(null, new DirectiveMetadataReader(), new Parser(new Lexer()), new CompilerCache());
+    });
+
+    function createElement(html) {
+      return DOM.createTemplate(html).content.firstChild;
+    }
+
+    function createView(pv) {
+      component = new TestComponent();
+      view = pv.instantiate(null);
+      view.hydrate(new Injector([]), null, component);
+      cd = view.changeDetector;
+    }
+
+    function compileWithTemplate(template) {
+      return compiler.compile(TestComponent, createElement(template));
+    }
+
+    it('should work in a template attribute', (done) => {
+      compileWithTemplate('<div><copy-me template="ng-if booleanCondition">hello</copy-me></div>').then((pv) => {
+        createView(pv);
+        cd.detectChanges();
+
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+        expect(DOM.getText(view.nodes[0])).toEqual('hello');
+        done();
+      });
+    });
+
+    it('should work in a template element', (done) => {
+      compileWithTemplate('<div><template [ng-if]="booleanCondition"><copy-me>hello2</copy-me></template></div>').then((pv) => {
+        createView(pv);
+        cd.detectChanges();
+
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+        expect(DOM.getText(view.nodes[0])).toEqual('hello2');
+        done();
+      });
+    });
+
+    it('should toggle node when condition changes', (done) => {
+      compileWithTemplate('<div><copy-me template="ng-if booleanCondition">hello</copy-me></div>').then((pv) => {
+        createView(pv);
+        
+        component.booleanCondition = false;
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(0);
+        expect(DOM.getText(view.nodes[0])).toEqual('');
+
+
+        component.booleanCondition = true;
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+        expect(DOM.getText(view.nodes[0])).toEqual('hello');
+
+        component.booleanCondition = false;
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(0);
+        expect(DOM.getText(view.nodes[0])).toEqual('');
+
+        done();
+      });
+    });
+
+    it('should update several nodes with ng-if', (done) => {
+      var templateString =
+      '<div>' +
+        '<copy-me template="ng-if numberCondition + 1 >= 2">helloNumber</copy-me>' +
+        '<copy-me template="ng-if stringCondition == \'foo\'">helloString</copy-me>' +
+        '<copy-me template="ng-if functionCondition(stringCondition, numberCondition)">helloFunction</copy-me>' +
+      '</div>';
+      compileWithTemplate(templateString).then((pv) => {
+        createView(pv);
+
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(3);
+        expect(DOM.getText(view.nodes[0])).toEqual('helloNumberhelloStringhelloFunction');
+
+        component.numberCondition = 0;
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+        expect(DOM.getText(view.nodes[0])).toEqual('helloString');
+
+        component.numberCondition = 1;
+        component.stringCondition = "bar";
+        cd.detectChanges();
+        expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+        expect(DOM.getText(view.nodes[0])).toEqual('helloNumber');
+        done();
+      });
+    });
+
+    
+    if (!IS_DARTIUM) {
+      it('should leave the element if the condition is a non-empty string (JS)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if stringCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+          cd.detectChanges();
+
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+          expect(DOM.getText(view.nodes[0])).toEqual('hello');
+          done();
+        });
+      });
+
+      it('should leave the element if the condition is an object (JS)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if objectCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+          cd.detectChanges();
+
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+          expect(DOM.getText(view.nodes[0])).toEqual('hello');
+          done();
+        });
+      });
+
+      it('should remove the element if the condition is null (JS)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if nullCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+          cd.detectChanges();
+
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(0);
+          expect(DOM.getText(view.nodes[0])).toEqual('');
+          done();
+        });
+      });
+
+      it('should not add the element twice if the condition goes from true to true (JS)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if numberCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+
+          cd.detectChanges();
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+          expect(DOM.getText(view.nodes[0])).toEqual('hello');
+
+          component.numberCondition = 2;
+          cd.detectChanges();
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(1);
+          expect(DOM.getText(view.nodes[0])).toEqual('hello');
+
+          done();
+        });
+      });
+
+      it('should not recreate the element if the condition goes from true to true (JS)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if numberCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+
+          cd.detectChanges();
+          DOM.addClass(view.nodes[0].childNodes[1], "foo");
+
+          component.numberCondition = 2;
+          cd.detectChanges();
+          expect(DOM.hasClass(view.nodes[0].childNodes[1], "foo")).toBe(true);
+
+          done();
+        });
+      });
+    } else {
+      it('should not create the element if the condition is not a boolean (DART)', (done) => {
+        compileWithTemplate('<div><copy-me template="ng-if numberCondition">hello</copy-me></div>').then((pv) => {
+          createView(pv);
+          expect(function(){cd.detectChanges();}).toThrowError();
+          expect(view.nodes[0].querySelectorAll('copy-me').length).toEqual(0);
+          expect(DOM.getText(view.nodes[0])).toEqual('');
+          done();
+        });
+      });
+    }
+
+  });
+}
+
+@Component({
+  selector: 'test-cmp',
+  template: new TemplateConfig({
+    inline: '',  // each test swaps with a custom template.
+    directives: [NgIf]
+  })
+})
+class TestComponent {
+  booleanCondition: boolean;
+  numberCondition: number;
+  stringCondition: string;
+  functionCondition: Function;
+  objectCondition: any;
+  nullCondition: any;
+  constructor() {
+    this.booleanCondition = true;
+    this.numberCondition = 1;
+    this.stringCondition = "foo";
+    this.functionCondition = function(s, n){
+      return s == "foo" && n == 1;
+    };
+    this.objectCondition = {};
+    this.nullCondition = null;
+  }
+}