From 62d92f8091a487fb94657d964ecea45a63f18e8e Mon Sep 17 00:00:00 2001
From: crisbeto <crisbeto@abv.bg>
Date: Fri, 30 Aug 2019 20:19:39 +0200
Subject: [PATCH] fix(ivy): unable to bind to properties that start with class
 or style (#32421)

Fixes Ivy picking up property bindings that start with `class` or `style` as if they're style bindings.

Fixes #32310

PR Close #32421
---
 .../src/render3/view/styling_builder.ts       |  7 +--
 packages/core/test/acceptance/styling_spec.ts | 44 ++++++++++++++++++-
 2 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/packages/compiler/src/render3/view/styling_builder.ts b/packages/compiler/src/render3/view/styling_builder.ts
index b7d06f64d4..ccf82f8b3b 100644
--- a/packages/compiler/src/render3/view/styling_builder.ts
+++ b/packages/compiler/src/render3/view/styling_builder.ts
@@ -149,9 +149,10 @@ export class StylingBuilder {
 
   registerInputBasedOnName(name: string, expression: AST, sourceSpan: ParseSourceSpan) {
     let binding: BoundStylingEntry|null = null;
-    const nameToMatch = name.substring(0, 5);  // class | style
-    const isStyle = nameToMatch === 'style';
-    const isClass = isStyle ? false : (nameToMatch === 'class');
+    const prefix = name.substring(0, 6);
+    const isStyle = name === 'style' || prefix === 'style.' || prefix === 'style!';
+    const isClass = !isStyle &&
+        (name === 'class' || name === 'className' || prefix === 'class.' || prefix === 'class!');
     if (isStyle || isClass) {
       const isMapBased = name.charAt(5) !== '.';         // style.prop or class.prop makes this a no
       const property = name.substr(isMapBased ? 5 : 6);  // the dot explains why there's a +1
diff --git a/packages/core/test/acceptance/styling_spec.ts b/packages/core/test/acceptance/styling_spec.ts
index 858943f1be..fb3724c7dd 100644
--- a/packages/core/test/acceptance/styling_spec.ts
+++ b/packages/core/test/acceptance/styling_spec.ts
@@ -5,7 +5,7 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import {Component, Directive, ElementRef, Input} from '@angular/core';
+import {Component, Directive, ElementRef, HostBinding, Input, ViewChild} from '@angular/core';
 import {ngDevModeResetPerfCounters} from '@angular/core/src/util/ng_dev_mode';
 import {TestBed} from '@angular/core/testing';
 import {By, DomSanitizer, SafeStyle} from '@angular/platform-browser';
@@ -631,4 +631,46 @@ describe('styling', () => {
 
     });
   });
+
+  it('should be able to name inputs starting with `class` or `style`', () => {
+    @Directive({selector: '[dir]'})
+    class Dir {
+      @Input('classesInSchool') classes = '';
+      @Input('styleOfClothing') style = '';
+    }
+
+    @Component({
+      template: '<span dir [classesInSchool]="classes" [styleOfClothing]="style"></span>',
+    })
+    class App {
+      @ViewChild(Dir, {static: false}) dir !: Dir;
+
+      classes = 'math';
+      style = '80s';
+    }
+
+    TestBed.configureTestingModule({declarations: [App, Dir]});
+    const fixture = TestBed.createComponent(App);
+    fixture.detectChanges();
+    const directive = fixture.componentInstance.dir;
+
+    expect(directive.classes).toBe('math');
+    expect(directive.style).toBe('80s');
+  });
+
+  it('should be able to bind to `className`', () => {
+    @Component({template: ''})
+    class App {
+      @HostBinding('className')
+      klass = 'one two';
+    }
+
+    TestBed.configureTestingModule({declarations: [App]});
+    const fixture = TestBed.createComponent(App);
+    fixture.detectChanges();
+    const classList = fixture.nativeElement.classList;
+
+    expect(classList.contains('one')).toBe(true);
+    expect(classList.contains('two')).toBe(true);
+  });
 });