refactor(compiler): Drop support for the deprecated `<template>`. Use `<ng-template>` instead (#22783)

BREAKING CHANGE:

The `<template>` tag was deprecated in Angular v4 to avoid collisions (i.e. when
using Web Components).

This commit removes support for `<template>`. `<ng-template>` should be used
instead.

BEFORE:

    <!-- html template -->
    <template>some template content</template>

    # tsconfig.json
    {
      # ...
      "angularCompilerOptions": {
        # ...
        # This option is no more supported and will have no effect
        "enableLegacyTemplate": [true|false]
      }
    }

AFTER:

    <!-- html template -->
    <ng-template>some template content</ng-template>

PR Close #22783

aio/content/guide/aot-compiler.md

@@ -215,13 +215,6 @@ value           | description
 
 This tells the compiler to print extra information while compiling templates.
 
-### *enableLegacyTemplate*
-
-The use of `<template>` element was deprecated starting in Angular 4.0 in favor of using
-`<ng-template>` to avoid colliding with the DOM's element of the same name. Setting this option to
-`true` enables the use of the deprecated `<template>` element . This option
-is `false` by default. This option might be required by some third-party Angular libraries.
-
 ### *disableExpressionLowering*
 
 The Angular template compiler transforms code that is used, or could be used, in an annotation

modules/benchmarks/src/old/naive_infinite_scroll/app.ts

@@ -25,9 +25,9 @@ import {ScrollAreaComponent} from './scroll_area';
     <div style="display: flex">
       <scroll-area id="testArea"></scroll-area>
     </div>
-    <div template="ngIf scrollAreas.length > 0">
+    <div *ngIf="scrollAreas.length > 0">
       <p>Following tables are only here to add weight to the UI:</p>
-      <scroll-area template="ngFor let scrollArea of scrollAreas"></scroll-area>
+      <scroll-area *ngFor="let scrollArea of scrollAreas"></scroll-area>
     </div>
   </div>`
 })

modules/benchmarks/src/old/naive_infinite_scroll/cells.ts

@@ -62,7 +62,7 @@ export class Stage {
   directives: [NgFor],
   template: `
       <div [style.width.px]="cellWidth">
-          <button template="ngFor let stage of stages"
+          <button *ngFor="let stage of stages"
                   [disabled]="stage.isDisabled"
                   [style.background-color]="stage.backgroundColor"
                   on-click="setStage(stage)">

modules/benchmarks/src/old/naive_infinite_scroll/scroll_area.ts

@@ -25,7 +25,7 @@ import {ScrollItemComponent} from './scroll_item';
             <div id="padding"></div>
             <div id="inner">
                 <scroll-item
-                    template="ngFor let item of visibleItems"
+                    *ngFor="let item of visibleItems"
                     [offering]="item">
                 </scroll-item>
             </div>

packages/compiler-cli/src/ngtools_api2.ts

@@ -50,7 +50,6 @@ export interface CompilerOptions extends ts.CompilerOptions {
   annotateForClosureCompiler?: boolean;
   annotationsAs?: 'decorators'|'static fields';
   trace?: boolean;
-  enableLegacyTemplate?: boolean;
   disableExpressionLowering?: boolean;
   i18nOutLocale?: string;
   i18nOutFormat?: string;

packages/compiler-cli/src/transformers/api.ts

@@ -125,9 +125,6 @@ export interface CompilerOptions extends ts.CompilerOptions {
   // Print extra information while running the compiler
   trace?: boolean;
 
-  // Whether to enable support for <template> and the template attribute (false by default)
-  enableLegacyTemplate?: boolean;
-
   // Whether to enable lowering expressions lambdas and expressions in a reference value
   // position.
   disableExpressionLowering?: boolean;

packages/compiler-cli/src/transformers/program.ts

@@ -828,7 +828,6 @@ function getAotCompilerOptions(options: CompilerOptions): AotCompilerOptions {
   return {
     locale: options.i18nInLocale,
     i18nFormat: options.i18nInFormat || options.i18nOutFormat, translations, missingTranslation,
-    enableLegacyTemplate: options.enableLegacyTemplate,
     enableSummariesForJit: options.enableSummariesForJit,
     preserveWhitespaces: options.preserveWhitespaces,
     fullTemplateTypeCheck: options.fullTemplateTypeCheck,

packages/compiler/design/separate_compilation.md

@@ -536,7 +536,6 @@ The recommended options for producing a ivy application are
 | `"renderer2BackPatching"`      | `true`   | implied     |
 | `"generateCodeForLibraries"`   | `true`   | default     |
 | `"annotationsAs"`              | `remove` | implied     |
-| `"enableLegacyTemplate"`       | `false`  | default     |
 | `"preserveWhitespaces"`        | `false`  | default     |
 | `"skipMetadataEmit"`           | `true`   | default     |
 | `"strictMetadataEmit"`         | `false`  | implied     |
@@ -574,7 +573,6 @@ The recommended options for producing a ivy library are:
 | `"renderer2BackPatching"`      | `false`  | default     |
 | `"generateCodeForLibraries"`   | `false`  |             |
 | `"annotationsAs"`              | `remove` | implied     |
-| `"enableLegacyTemplate"`       | `false`  | default     |
 | `"preserveWhitespaces"`        | `false`  | default     |
 | `"skipMetadataEmit"`           | `false`  |             |
 | `"strictMetadataEmit"`         | `true `  |             |
@@ -598,25 +596,21 @@ depending on the target:
 |                   | `"renderer2BackPatching"`      | `true`       | enforced    |
 |                   | `"generateCodeForLibraries"`   | `true`       |             |
 |                   | `"annotationsAs"`              | `remove`     |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 |                   | `"preserveWhitespaces"`        | `false`      |             |
 |                   | `"skipMetadataEmit"`           | `false`      |             |
 |                   | `"strictMetadataEmit"`         | `true`       |             |
 |                   | `"skipTemplateCodegen"`        | `false`      |             |
 |                   | `"fullTemplateTypeCheck"`      | `true`       |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 |                   |                                |              |             |
 | `"library"`       | `"generateRenderer2Factories"` | `false`      | enforced    |
 |                   | `"renderer2BackPatching"`      | `false`      | enforced    |
 |                   | `"generateCodeForLibraries"`   | `false`      | enforced    |
 |                   | `"annotationsAs"`              | `decorators` |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 |                   | `"preserveWhitespaces"`        | `false`      |             |
 |                   | `"skipMetadataEmit"`           | `false`      | enforced    |
 |                   | `"strictMetadataEmit"`         | `true`       |             |
 |                   | `"skipTemplateCodegen"`        | `false`      | enforced    |
 |                   | `"fullTemplateTypeCheck"`      | `true`       |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 |                   |                                |              |             |
 | `"package"`       | `"flatModuleOutFile"`          |              | required    |
 |                   | `"flatModuleId"`               |              | required    |
@@ -625,13 +619,11 @@ depending on the target:
 |                   | `"renderer2BackPatching"`      | `false`      | enforced    |
 |                   | `"generateCodeForLibraries"`   | `false`      | enforced    |
 |                   | `"annotationsAs"`              | `remove`     |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 |                   | `"preserveWhitespaces"`        | `false`      |             |
 |                   | `"skipMetadataEmit"`           | `false`      | enforced    |
 |                   | `"strictMetadataEmit"`         | `true`       |             |
 |                   | `"skipTemplateCodegen"`        | `false`      | enforced    |
 |                   | `"fullTemplateTypeCheck"`      | `true`       |             |
-|                   | `"enableLegacyTemplate"`       | `false`      |             |
 
 Options that are marked "enforced" are reported as an error if they are
 explicitly set to a value different from what is specified here. The options

packages/compiler/src/aot/compiler_factory.ts

@@ -70,7 +70,6 @@ export function createAotCompiler(
   const config = new CompilerConfig({
     defaultEncapsulation: ViewEncapsulation.Emulated,
     useJit: false,
-    enableLegacyTemplate: options.enableLegacyTemplate === true,
     missingTranslation: options.missingTranslation,
     preserveWhitespaces: options.preserveWhitespaces,
     strictInjectionParameters: options.strictInjectionParameters,

packages/compiler/src/aot/compiler_options.ts

@@ -13,7 +13,6 @@ export interface AotCompilerOptions {
   i18nFormat?: string;
   translations?: string;
   missingTranslation?: MissingTranslationStrategy;
-  enableLegacyTemplate?: boolean;
   enableSummariesForJit?: boolean;
   preserveWhitespaces?: boolean;
   fullTemplateTypeCheck?: boolean;

packages/compiler/src/config.ts

@@ -14,9 +14,6 @@ import {noUndefined} from './util';
 
 export class CompilerConfig {
   public defaultEncapsulation: ViewEncapsulation|null;
-  // Whether to support the `<template>` tag and the `template` attribute to define angular
-  // templates. They have been deprecated in 4.x, `<ng-template>` should be used instead.
-  public enableLegacyTemplate: boolean;
   public useJit: boolean;
   public jitDevMode: boolean;
   public missingTranslation: MissingTranslationStrategy|null;
@@ -25,13 +22,11 @@ export class CompilerConfig {
 
   constructor(
       {defaultEncapsulation = ViewEncapsulation.Emulated, useJit = true, jitDevMode = false,
-       missingTranslation = null, enableLegacyTemplate, preserveWhitespaces,
+       missingTranslation = null, preserveWhitespaces, strictInjectionParameters}: {
-       strictInjectionParameters}: {
         defaultEncapsulation?: ViewEncapsulation,
         useJit?: boolean,
         jitDevMode?: boolean,
         missingTranslation?: MissingTranslationStrategy,
-        enableLegacyTemplate?: boolean,
         preserveWhitespaces?: boolean,
         strictInjectionParameters?: boolean,
       } = {}) {
@@ -39,7 +34,6 @@ export class CompilerConfig {
     this.useJit = !!useJit;
     this.jitDevMode = !!jitDevMode;
     this.missingTranslation = missingTranslation;
-    this.enableLegacyTemplate = enableLegacyTemplate === true;
     this.preserveWhitespaces = preserveWhitespacesDefault(noUndefined(preserveWhitespaces));
     this.strictInjectionParameters = strictInjectionParameters === true;
   }

packages/compiler/src/ml_parser/tags.ts

@@ -71,7 +71,6 @@ export function mergeNsAndName(prefix: string, localName: string): string {
 // This list is not exhaustive to keep the compiler footprint low.
 // The `{` / `ƫ` syntax should be used when the named character reference does not
 // exist.
-
 export const NAMED_ENTITIES: {[k: string]: string} = {
   'Aacute': '\u00C1',
   'aacute': '\u00E1',

packages/compiler/src/template_parser/template_parser.ts

@@ -55,20 +55,11 @@ const IDENT_PROPERTY_IDX = 9;
 // Group 10 = identifier inside ()
 const IDENT_EVENT_IDX = 10;
 
-// deprecated in 4.x
-const TEMPLATE_ELEMENT = 'template';
-// deprecated in 4.x
-const TEMPLATE_ATTR = 'template';
 const TEMPLATE_ATTR_PREFIX = '*';
 const CLASS_ATTR = 'class';
 
 const TEXT_CSS_SELECTOR = CssSelector.parse('*')[0];
 
-const TEMPLATE_ELEMENT_DEPRECATION_WARNING =
-    'The <template> element is deprecated. Use <ng-template> instead';
-const TEMPLATE_ATTR_DEPRECATION_WARNING =
-    'The template attribute is deprecated. Use an ng-template element instead.';
-
 let warningCounts: {[warning: string]: number} = {};
 
 function warnOnlyOnce(warnings: string[]): (warning: ParseError) => boolean {
@@ -109,10 +100,7 @@ export class TemplateParser {
       preserveWhitespaces: boolean): {template: TemplateAst[], pipes: CompilePipeSummary[]} {
     const result = this.tryParse(
         component, template, directives, pipes, schemas, templateUrl, preserveWhitespaces);
-    const warnings =
+    const warnings = result.errors !.filter(error => error.level === ParseErrorLevel.WARNING);
-        result.errors !.filter(error => error.level === ParseErrorLevel.WARNING)
-            .filter(warnOnlyOnce(
-                [TEMPLATE_ATTR_DEPRECATION_WARNING, TEMPLATE_ELEMENT_DEPRECATION_WARNING]));
 
     const errors = result.errors !.filter(error => error.level === ParseErrorLevel.ERROR);
 
@@ -295,9 +283,7 @@ class TemplateParseVisitor implements html.Visitor {
 
     let hasInlineTemplates = false;
     const attrs: AttrAst[] = [];
-    const isTemplateElement = isTemplate(
+    const isTemplateElement = isNgTemplate(element.name);
-        element, this.config.enableLegacyTemplate,
-        (m: string, span: ParseSourceSpan) => this._reportError(m, span, ParseErrorLevel.WARNING));
 
     element.attrs.forEach(attr => {
       const hasBinding = this._parseAttr(
@@ -306,13 +292,9 @@ class TemplateParseVisitor implements html.Visitor {
 
       let templateBindingsSource: string|undefined;
       let prefixToken: string|undefined;
-      let normalizedName = this._normalizeAttributeName(attr.name);
+      const normalizedName = this._normalizeAttributeName(attr.name);
 
-      if (this.config.enableLegacyTemplate && normalizedName == TEMPLATE_ATTR) {
+      if (normalizedName.startsWith(TEMPLATE_ATTR_PREFIX)) {
-        this._reportError(
-            TEMPLATE_ATTR_DEPRECATION_WARNING, attr.sourceSpan, ParseErrorLevel.WARNING);
-        templateBindingsSource = attr.value;
-      } else if (normalizedName.startsWith(TEMPLATE_ATTR_PREFIX)) {
         templateBindingsSource = attr.value;
         prefixToken = normalizedName.substring(TEMPLATE_ATTR_PREFIX.length) + ':';
       }
@@ -321,7 +303,7 @@ class TemplateParseVisitor implements html.Visitor {
       if (hasTemplateBinding) {
         if (hasInlineTemplates) {
           this._reportError(
-              `Can't have multiple template bindings on one element. Use only one attribute named 'template' or prefixed with *`,
+              `Can't have multiple template bindings on one element. Use only one attribute prefixed with *`,
               attr.sourceSpan);
         }
         hasInlineTemplates = true;
@@ -400,7 +382,7 @@ class TemplateParseVisitor implements html.Visitor {
 
     if (hasInlineTemplates) {
       const templateQueryStartIndex = this.contentQueryStartId;
-      const templateSelector = createElementCssSelector(TEMPLATE_ELEMENT, templateMatchableAttrs);
+      const templateSelector = createElementCssSelector('ng-template', templateMatchableAttrs);
       const {directives: templateDirectiveMetas} =
           this._parseDirectives(this.selectorMatcher, templateSelector);
       const templateBoundDirectivePropNames = new Set<string>();
@@ -909,19 +891,3 @@ function isEmptyExpression(ast: AST): boolean {
   }
   return ast instanceof EmptyExpr;
 }
-
-// `template` is deprecated in 4.x
-function isTemplate(
-    el: html.Element, enableLegacyTemplate: boolean,
-    reportDeprecation: (m: string, span: ParseSourceSpan) => void): boolean {
-  if (isNgTemplate(el.name)) return true;
-  const tagNoNs = splitNsName(el.name)[1];
-  // `<template>` is HTML and case insensitive
-  if (tagNoNs.toLowerCase() === TEMPLATE_ELEMENT) {
-    if (enableLegacyTemplate && tagNoNs.toLowerCase() === TEMPLATE_ELEMENT) {
-      reportDeprecation(TEMPLATE_ELEMENT_DEPRECATION_WARNING, el.sourceSpan !);
-      return true;
-    }
-  }
-  return false;
-}

packages/compiler/test/ml_parser/html_parser_spec.ts

@@ -32,10 +32,6 @@ import {humanizeDom, humanizeDomSourceSpans, humanizeLineColumn} from './ast_spe
         });
 
         it('should parse text nodes inside <ng-template> elements', () => {
-          // deprecated in 4.0
-          expect(humanizeDom(parser.parse('<template>a</template>', 'TestComp'))).toEqual([
-            [html.Element, 'template', 0], [html.Text, 'a', 1]
-          ]);
           expect(humanizeDom(parser.parse('<ng-template>a</ng-template>', 'TestComp'))).toEqual([
             [html.Element, 'ng-template', 0], [html.Text, 'a', 1]
           ]);
@@ -62,8 +58,6 @@ import {humanizeDom, humanizeDomSourceSpans, humanizeLineColumn} from './ast_spe
         });
 
         it('should parse elements inside  <ng-template> elements', () => {
-          expect(humanizeDom(parser.parse('<template><span></span></template>', 'TestComp')))
-              .toEqual([[html.Element, 'template', 0], [html.Element, 'span', 1]]);
           expect(humanizeDom(parser.parse('<ng-template><span></span></ng-template>', 'TestComp')))
               .toEqual([[html.Element, 'ng-template', 0], [html.Element, 'span', 1]]);
         });
@@ -175,10 +169,6 @@ import {humanizeDom, humanizeDomSourceSpans, humanizeLineColumn} from './ast_spe
         });
 
         it('should not add the requiredParent when the parent is a <ng-template>', () => {
-          expect(humanizeDom(parser.parse('<template><tr></tr></template>', 'TestComp'))).toEqual([
-            [html.Element, 'template', 0],
-            [html.Element, 'tr', 1],
-          ]);
           expect(humanizeDom(parser.parse('<ng-template><tr></tr></ng-template>', 'TestComp')))
               .toEqual([
                 [html.Element, 'ng-template', 0],
@@ -282,10 +272,6 @@ import {humanizeDom, humanizeDomSourceSpans, humanizeLineColumn} from './ast_spe
         });
 
         it('should parse attributes on <ng-template> elements', () => {
-          expect(humanizeDom(parser.parse('<template k="v"></template>', 'TestComp'))).toEqual([
-            [html.Element, 'template', 0],
-            [html.Attribute, 'k', 'v'],
-          ]);
           expect(humanizeDom(parser.parse('<ng-template k="v"></ng-template>', 'TestComp')))
               .toEqual([
                 [html.Element, 'ng-template', 0],

packages/compiler/test/render3/mock_compile.ts

@@ -158,7 +158,6 @@ function doCompile(
   const config = new CompilerConfig({
     defaultEncapsulation: ViewEncapsulation.Emulated,
     useJit: false,
-    enableLegacyTemplate: options.enableLegacyTemplate === true,
     missingTranslation: options.missingTranslation,
     preserveWhitespaces: options.preserveWhitespaces,
     strictInjectionParameters: options.strictInjectionParameters,

packages/compiler/test/template_parser/template_parser_spec.ts

@@ -336,7 +336,6 @@ class ArrayConsole implements Console {
       TestBed.configureCompiler({
         providers: [
           {provide: Console, useValue: console},
-          {provide: CompilerConfig, useValue: new CompilerConfig({enableLegacyTemplate: true})}
         ],
       });
     });
@@ -812,6 +811,35 @@ Binding to attribute 'onEvent' is disallowed for security reasons ("<my-componen
             ]
           ]);
         });
+
+        it('should support * directives', () => {
+          expect(humanizeTplAst(parse('<div *ngIf>', [ngIf]))).toEqual([
+            [EmbeddedTemplateAst],
+            [DirectiveAst, ngIf],
+            [BoundDirectivePropertyAst, 'ngIf', 'null'],
+            [ElementAst, 'div'],
+          ]);
+        });
+
+        it('should support <ng-template>', () => {
+          expect(humanizeTplAst(parse('<ng-template>', []))).toEqual([
+            [EmbeddedTemplateAst],
+          ]);
+        });
+
+        it('should treat <template> as a regular tag', () => {
+          expect(humanizeTplAst(parse('<template>', []))).toEqual([
+            [ElementAst, 'template'],
+          ]);
+        });
+
+        it('should not special case the template attribute', () => {
+          expect(humanizeTplAst(parse('<p template="ngFor">', []))).toEqual([
+            [ElementAst, 'p'],
+            [AttrAst, 'template', 'ngFor'],
+          ]);
+        });
+
       });
 
       describe('events', () => {
@@ -852,17 +880,11 @@ Binding to attribute 'onEvent' is disallowed for security reasons ("<my-componen
            () => {
              const dirA =
                  compileDirectiveMetadataCreate({
-                   selector: 'template,ng-template',
+                   selector: 'ng-template',
                    outputs: ['e'],
                    type: createTypeMeta({reference: {filePath: someModuleUrl, name: 'DirA'}})
                  }).toSummary();
 
-             expect(humanizeTplAst(parse('<template (e)="f"></template>', [dirA]))).toEqual([
-               [EmbeddedTemplateAst],
-               [BoundEventAst, 'e', null, 'f'],
-               [DirectiveAst, dirA],
-             ]);
-
              expect(humanizeTplAst(parse('<ng-template (e)="f"></ng-template>', [dirA]))).toEqual([
                [EmbeddedTemplateAst],
                [BoundEventAst, 'e', null, 'f'],
@@ -952,7 +974,7 @@ Binding to attribute 'onEvent' is disallowed for security reasons ("<my-componen
         it('should locate directives in inline templates', () => {
           const dirTemplate =
               compileDirectiveMetadataCreate({
-                selector: 'template',
+                selector: 'ng-template',
                 type: createTypeMeta({reference: {filePath: someModuleUrl, name: 'onTemplate'}})
               }).toSummary();
           expect(humanizeTplAst(parse('<div *ngIf="cond">', [ngIf, dirTemplate]))).toEqual([
@@ -1460,8 +1482,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
 
         it('should not throw error when there is same reference name in different templates',
            () => {
-             expect(() => parse('<div #a><template #a><span>OK</span></template></div>', []))
-                 .not.toThrowError();
              expect(() => parse('<div #a><ng-template #a><span>OK</span></ng-template></div>', []))
                  .not.toThrowError();
            });
@@ -1500,20 +1520,12 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
         beforeEach(() => { reflector = new JitReflector(); });
 
         it('should create embedded templates for <ng-template> elements', () => {
-          expect(humanizeTplAst(parse('<template></template>', [
-          ]))).toEqual([[EmbeddedTemplateAst]]);
-          expect(humanizeTplAst(parse('<TEMPLATE></TEMPLATE>', [
-          ]))).toEqual([[EmbeddedTemplateAst]]);
           expect(humanizeTplAst(parse('<ng-template></ng-template>', [
           ]))).toEqual([[EmbeddedTemplateAst]]);
         });
 
         it('should create embedded templates for <ng-template> elements regardless the namespace',
            () => {
-             expect(humanizeTplAst(parse('<svg><template></template></svg>', []))).toEqual([
-               [ElementAst, ':svg:svg'],
-               [EmbeddedTemplateAst],
-             ]);
              expect(humanizeTplAst(parse('<svg><ng-template></ng-template></svg>', []))).toEqual([
                [ElementAst, ':svg:svg'],
                [EmbeddedTemplateAst],
@@ -1521,12 +1533,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
            });
 
         it('should support references via #...', () => {
-          expect(humanizeTplAst(parse('<template #a>', []))).toEqual([
-            [EmbeddedTemplateAst],
-            [
-              ReferenceAst, 'a', createTokenForExternalReference(reflector, Identifiers.TemplateRef)
-            ],
-          ]);
           expect(humanizeTplAst(parse('<ng-template #a>', []))).toEqual([
             [EmbeddedTemplateAst],
             [
@@ -1536,12 +1542,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
         });
 
         it('should support references via ref-...', () => {
-          expect(humanizeTplAst(parse('<template ref-a>', []))).toEqual([
-            [EmbeddedTemplateAst],
-            [
-              ReferenceAst, 'a', createTokenForExternalReference(reflector, Identifiers.TemplateRef)
-            ]
-          ]);
           expect(humanizeTplAst(parse('<ng-template ref-a>', []))).toEqual([
             [EmbeddedTemplateAst],
             [
@@ -1551,10 +1551,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
         });
 
         it('should parse variables via let-...', () => {
-          expect(humanizeTplAst(parse('<template let-a="b">', []))).toEqual([
-            [EmbeddedTemplateAst],
-            [VariableAst, 'a', 'b'],
-          ]);
           expect(humanizeTplAst(parse('<ng-template let-a="b">', []))).toEqual([
             [EmbeddedTemplateAst],
             [VariableAst, 'a', 'b'],
@@ -1567,10 +1563,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
                 selector: '[a]',
                 type: createTypeMeta({reference: {filePath: someModuleUrl, name: 'DirA'}})
               }).toSummary();
-          expect(humanizeTplAst(parse('<template let-a="b"></template>', [dirA]))).toEqual([
-            [EmbeddedTemplateAst],
-            [VariableAst, 'a', 'b'],
-          ]);
           expect(humanizeTplAst(parse('<ng-template let-a="b"></ng-template>', [dirA]))).toEqual([
             [EmbeddedTemplateAst],
             [VariableAst, 'a', 'b'],
@@ -1580,30 +1572,6 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
       });
 
       describe('inline templates', () => {
-        it('should wrap the element into an EmbeddedTemplateAST', () => {
-          expect(humanizeTplAst(parse('<div template>', []))).toEqual([
-            [EmbeddedTemplateAst],
-            [ElementAst, 'div'],
-          ]);
-        });
-
-        it('should wrap the element with data-template attribute into an EmbeddedTemplateAST ',
-           () => {
-             expect(humanizeTplAst(parse('<div data-template>', []))).toEqual([
-               [EmbeddedTemplateAst],
-               [ElementAst, 'div'],
-             ]);
-           });
-
-        it('should parse bound properties', () => {
-          expect(humanizeTplAst(parse('<div template="ngIf test">', [ngIf]))).toEqual([
-            [EmbeddedTemplateAst],
-            [DirectiveAst, ngIf],
-            [BoundDirectivePropertyAst, 'ngIf', 'test'],
-            [ElementAst, 'div'],
-          ]);
-        });
-
         it('should report an error on variables declared with #', () => {
           expect(() => humanizeTplAst(parse('<div *ngIf="#a=b">', [])))
               .toThrowError(/Parser Error: Unexpected token # at column 1/);
@@ -1646,7 +1614,7 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
                   selector: '[b]',
                   type: createTypeMeta({reference: {filePath: someModuleUrl, name: 'DirB'}})
                 }).toSummary();
-            expect(humanizeTplAst(parse('<div template="a b" b>', [dirA, dirB]))).toEqual([
+            expect(humanizeTplAst(parse('<div *a="b" b>', [dirA, dirB]))).toEqual([
               [EmbeddedTemplateAst], [DirectiveAst, dirA], [BoundDirectivePropertyAst, 'a', 'b'],
               [ElementAst, 'div'], [AttrAst, 'b', ''], [DirectiveAst, dirB]
             ]);
@@ -1658,8 +1626,12 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
                   selector: '[a]',
                   type: createTypeMeta({reference: {filePath: someModuleUrl, name: 'DirA'}})
                 }).toSummary();
-            expect(humanizeTplAst(parse('<div template="let a=b">', [dirA]))).toEqual([
+            expect(
-              [EmbeddedTemplateAst], [VariableAst, 'a', 'b'], [ElementAst, 'div']
+                humanizeTplAst(parse('<ng-template let-a="b"><div></div></ng-template>', [dirA])))
+                .toEqual([
+                  [EmbeddedTemplateAst],
+                  [VariableAst, 'a', 'b'],
+                  [ElementAst, 'div'],
                 ]);
           });
 
@@ -1760,13 +1732,11 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
 
       describe('embedded templates', () => {
         it('should project embedded templates with wildcard selector', () => {
-          expect(humanizeContentProjection(parse(
+          expect(humanizeContentProjection(
-                     '<div><template></template><ng-template></ng-template></div>',
+                     parse('<div><ng-template></ng-template></div>', [createComp('div', ['*'])])))
-                     [createComp('div', ['*'])])))
               .toEqual([
                 ['div', null],
                 ['template', 0],
-                ['template', 0],
               ]);
         });
 
@@ -1848,14 +1818,12 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
         });
 
         it('should override <ng-template>', () => {
-          expect(
+          expect(humanizeContentProjection(parse(
-              humanizeContentProjection(parse(
+                     '<div><ng-template ngProjectAs="b"></ng-template></div>',
-                  '<div><template ngProjectAs="b"></template><ng-template ngProjectAs="b"></ng-template></div>',
                      [createComp('div', ['template', 'b'])])))
               .toEqual([
                 ['div', null],
                 ['template', 1],
-                ['template', 1],
               ]);
         });
 
@@ -1894,26 +1862,14 @@ Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>
                 `<ng-content> element cannot have content. ("[ERROR ->]<ng-content>content</ng-content>"): TestComp@0:0`);
       });
 
-      it('should treat *attr on a template element as valid', () => {
+      it('should treat *attr on a template element as valid',
-        expect(() => parse('<template *ngIf>', [])).not.toThrowError();
+         () => { expect(() => parse('<ng-template *ngIf>', [])).not.toThrowError(); });
-        expect(() => parse('<ng-template *ngIf>', [])).not.toThrowError();
-      });
-
-      it('should treat template attribute on a template element as valid', () => {
-        expect(() => parse('<template template="ngIf">', [])).not.toThrowError();
-        expect(() => parse('<ng-template template="ngIf">', [])).not.toThrowError();
-      });
 
       it('should report when multiple *attrs are used on the same element', () => {
         expect(() => parse('<div *ngIf *ngFor>', [])).toThrowError(`Template parse errors:
-Can't have multiple template bindings on one element. Use only one attribute named 'template' or prefixed with * ("<div *ngIf [ERROR ->]*ngFor>"): TestComp@0:11`);
+Can't have multiple template bindings on one element. Use only one attribute prefixed with * ("<div *ngIf [ERROR ->]*ngFor>"): TestComp@0:11`);
       });
 
-      it('should report when mix of template and *attrs are used on the same element', () => {
-        expect(() => parse('<span template="ngIf" *ngFor>', []))
-            .toThrowError(`Template parse errors:
-Can't have multiple template bindings on one element. Use only one attribute named 'template' or prefixed with * ("<span template="ngIf" [ERROR ->]*ngFor>"): TestComp@0:22`);
-      });
 
       it('should report invalid property names', () => {
         expect(() => parse('<div [invalidProp]></div>', [])).toThrowError(`Template parse errors:
@@ -1977,12 +1933,6 @@ Parser Error: Unexpected token 'b' at column 3 in [a b] in TestComp@0:5 ("<div [
                  template: compileTemplateMetadata({ngContentSelectors: []})
                }).toSummary();
 
-           expect(() => parse('<template [a]="b" (e)="f"></template>', [dirA]))
-               .toThrowError(`Template parse errors:
-Event binding e not emitted by any directive on an embedded template. Make sure that the event name is spelled correctly and all directives are listed in the "@NgModule.declarations". ("<template [a]="b" [ERROR ->](e)="f"></template>"): TestComp@0:18
-Components on an embedded template: DirA ("[ERROR ->]<template [a]="b" (e)="f"></template>"): TestComp@0:0
-Property binding a not used by any directive on an embedded template. Make sure that the property name is spelled correctly and all directives are listed in the "@NgModule.declarations". ("[ERROR ->]<template [a]="b" (e)="f"></template>"): TestComp@0:0`);
-
            expect(() => parse('<ng-template [a]="b" (e)="f"></ng-template>', [dirA]))
                .toThrowError(`Template parse errors:
 Event binding e not emitted by any directive on an embedded template. Make sure that the event name is spelled correctly and all directives are listed in the "@NgModule.declarations". ("<ng-template [a]="b" [ERROR ->](e)="f"></ng-template>"): TestComp@0:21
@@ -2093,8 +2043,6 @@ Property binding a not used by any directive on an embedded template. Make sure
       });
 
       it('should support embedded template', () => {
-        expect(humanizeTplAstSourceSpans(parse('<template></template>', [
-        ]))).toEqual([[EmbeddedTemplateAst, '<template>']]);
         expect(humanizeTplAstSourceSpans(parse('<ng-template></ng-template>', [
         ]))).toEqual([[EmbeddedTemplateAst, '<ng-template>']]);
       });
@@ -2112,10 +2060,6 @@ Property binding a not used by any directive on an embedded template. Make sure
       });
 
       it('should support variables', () => {
-        expect(humanizeTplAstSourceSpans(parse('<template let-a="b"></template>', []))).toEqual([
-          [EmbeddedTemplateAst, '<template let-a="b">'],
-          [VariableAst, 'a', 'b', 'let-a="b"'],
-        ]);
         expect(humanizeTplAstSourceSpans(parse('<ng-template let-a="b"></ng-template>', [])))
             .toEqual([
               [EmbeddedTemplateAst, '<ng-template let-a="b">'],
@@ -2342,47 +2286,6 @@ The pipe 'test' could not be found ("{{[ERROR ->]a | test}}"): TestComp@0:2`);
         ...humanizedExpandedForm, ...humanizedExpandedForm
       ]);
     });
-
   });
 
-  describe('Template Parser - `<template>` support disabled by default', () => {
-    beforeEach(() => {
-      TestBed.configureCompiler({
-        providers: [
-          {provide: Console, useValue: console},
-          {provide: CompilerConfig, useValue: new CompilerConfig()}
-        ],
-      });
-    });
-
-    commonBeforeEach();
-
-    it('should support * directives', () => {
-      expect(humanizeTplAst(parse('<div *ngIf>', [ngIf]))).toEqual([
-        [EmbeddedTemplateAst],
-        [DirectiveAst, ngIf],
-        [BoundDirectivePropertyAst, 'ngIf', 'null'],
-        [ElementAst, 'div'],
-      ]);
-    });
-
-    it('should support <ng-template>', () => {
-      expect(humanizeTplAst(parse('<ng-template>', []))).toEqual([
-        [EmbeddedTemplateAst],
-      ]);
-    });
-
-    it('should treat <template> as a regular tag', () => {
-      expect(humanizeTplAst(parse('<template>', []))).toEqual([
-        [ElementAst, 'template'],
-      ]);
-    });
-
-    it('should not special case the template attribute', () => {
-      expect(humanizeTplAst(parse('<p template="ngFor">', []))).toEqual([
-        [ElementAst, 'p'],
-        [AttrAst, 'template', 'ngFor'],
-      ]);
-    });
-  });
 })();

packages/core/src/linker/compiler.ts

@@ -90,9 +90,6 @@ export type CompilerOptions = {
   defaultEncapsulation?: ViewEncapsulation,
   providers?: StaticProvider[],
   missingTranslation?: MissingTranslationStrategy,
-  // Whether to support the `<template>` tag and the `template` attribute to define angular
-  // templates. They have been deprecated in 4.x, `<ng-template>` should be used instead.
-  enableLegacyTemplate?: boolean,
   preserveWhitespaces?: boolean,
 };
 

packages/core/test/linker/integration_spec.ts

@@ -38,14 +38,7 @@ const ANCHOR_ELEMENT = new InjectionToken('AnchorElement');
 function declareTests({useJit}: {useJit: boolean}) {
   describe('integration tests', function() {
 
-    beforeEach(() => {
+    beforeEach(() => { TestBed.configureCompiler({useJit}); });
-      TestBed.configureCompiler({
-        useJit,
-        providers: [
-          {provide: CompilerConfig, useValue: new CompilerConfig({enableLegacyTemplate: true})}
-        ]
-      });
-    });
 
     describe('react to record changes', function() {
       it('should consume text node changes', () => {
@@ -420,22 +413,6 @@ function declareTests({useJit}: {useJit: boolean}) {
         expect(getDOM().isCommentNode(childNodesOfWrapper[0])).toBe(true);
       });
 
-      it('should support template directives via `template` attribute.', () => {
-        TestBed.configureTestingModule({declarations: [MyComp, SomeViewport]});
-        const template =
-            '<span template="some-viewport: let greeting=someTmpl">{{greeting}}</span>';
-        TestBed.overrideComponent(MyComp, {set: {template}});
-        const fixture = TestBed.createComponent(MyComp);
-
-        fixture.detectChanges();
-
-        const childNodesOfWrapper = getDOM().childNodes(fixture.nativeElement);
-        // 1 template + 2 copies.
-        expect(childNodesOfWrapper.length).toBe(3);
-        expect(childNodesOfWrapper[1]).toHaveText('hello');
-        expect(childNodesOfWrapper[2]).toHaveText('again');
-      });
-
       it('should allow to transplant TemplateRefs into other ViewContainers', () => {
         TestBed.configureTestingModule({
           declarations: [

packages/platform-browser-dynamic/src/compiler_factory.ts

@@ -162,7 +162,6 @@ export class JitCompilerFactory implements CompilerFactory {
       useJit: true,
       defaultEncapsulation: ViewEncapsulation.Emulated,
       missingTranslation: MissingTranslationStrategy.Warning,
-      enableLegacyTemplate: false,
     };
 
     this._defaultOptions = [compilerOptions, ...defaultOptions];
@@ -182,7 +181,6 @@ export class JitCompilerFactory implements CompilerFactory {
             // from the app providers
             defaultEncapsulation: opts.defaultEncapsulation,
             missingTranslation: opts.missingTranslation,
-            enableLegacyTemplate: opts.enableLegacyTemplate,
             preserveWhitespaces: opts.preserveWhitespaces,
           });
         },
@@ -200,7 +198,6 @@ function _mergeOptions(optionsArr: CompilerOptions[]): CompilerOptions {
     defaultEncapsulation: _lastDefined(optionsArr.map(options => options.defaultEncapsulation)),
     providers: _mergeArrays(optionsArr.map(options => options.providers !)),
     missingTranslation: _lastDefined(optionsArr.map(options => options.missingTranslation)),
-    enableLegacyTemplate: _lastDefined(optionsArr.map(options => options.enableLegacyTemplate)),
     preserveWhitespaces: _lastDefined(optionsArr.map(options => options.preserveWhitespaces)),
   };
 }

tools/public_api_guard/core/core.d.ts

@@ -112,7 +112,6 @@ export declare type CompilerOptions = {
     defaultEncapsulation?: ViewEncapsulation;
     providers?: StaticProvider[];
     missingTranslation?: MissingTranslationStrategy;
-    enableLegacyTemplate?: boolean;
     preserveWhitespaces?: boolean;
 };