build: update tooling to generate APF version 16 packages (#26906)

alan-agius4 · alan-agius4 · commit 5fe2280839f0 · 2023-04-12T13:53:18.000Z
This commit updates the tooling to generate APF version 16 packages. See angular/angular#49332 for more information. (cherry picked from commit 44c3c52)
diff --git a/WORKSPACE b/WORKSPACE
@@ -73,7 +73,8 @@ yarn_install(
         "//:.yarn/releases/yarn-1.22.17.cjs",
         "//:.yarnrc",
         "//:tools/postinstall/apply-patches.js",
-        "//:tools/postinstall/patches/@angular+bazel+16.0.0-next.0.patch",
+        "//:tools/postinstall/patches/@angular+bazel+16.0.0-next.6.patch",
+        "//:tools/postinstall/patches/@bazel+concatjs+5.8.1.patch",
     ],
     # Currently disabled due to:
     #  1. Missing Windows support currently.
diff --git a/integration/linker/link-packages-test.mjs b/integration/linker/link-packages-test.mjs
@@ -56,7 +56,7 @@ if (failedPackages) {
  * @returns An object containing linker failures and passed files.
  */
 function testPackage(pkg) {
-  const entryPointFesmFiles = glob.sync(`+(fesm2015|fesm2020)/**/*.mjs`, {cwd: pkg.pkgPath});
+  const entryPointFesmFiles = glob.sync(`fesm2022/**/*.mjs`, {cwd: pkg.pkgPath});
   const passedFiles = [];
   const failures = [];
 
diff --git a/package.json b/package.json
@@ -73,7 +73,7 @@
     "@angular-devkit/build-angular": "^16.0.0-next.7",
     "@angular-devkit/core": "^16.0.0-next.7",
     "@angular-devkit/schematics": "^16.0.0-next.7",
-    "@angular/bazel": "https://github.com/angular/bazel-builds.git#8b1e899d38c5781662ff01812d5e71aa014b861c",
+    "@angular/bazel": "https://github.com/angular/bazel-builds.git#bac9c1abe1e6ac1801fbbccb53353a1ed7126469",
     "@angular/build-tooling": "https://github.com/angular/dev-infra-private-build-tooling-builds.git#fb897a1ae4b084da69f77b3fc09848b57a321421",
     "@angular/cli": "^16.0.0-next.7",
     "@angular/compiler-cli": "^16.0.0-next.7",
diff --git a/src/bazel-tsconfig-build.json b/src/bazel-tsconfig-build.json
@@ -20,14 +20,16 @@
     "importHelpers": true,
     "strictBindCallApply": true,
     "esModuleInterop": true,
+    // Keep the below in sync with https://github.com/angular/angular/blob/f9b821f07d8dba57a6a7e5fc127dc096247424aa/packages/bazel/src/ng_module/ng_module.bzl#L214
+    "useDefineForClassFields": false,
     "newLine": "lf",
     // Bazel either uses "umd" or "esnext". We replicate this here for IDE support.
     // https://github.com/bazelbuild/rules_typescript/blob/master/internal/common/tsconfig.bzl#L199
     "module": "esnext",
     "moduleResolution": "node",
     "sourceMap": true,
     "inlineSources": true,
-    "target": "es2020",
+    "target": "es2022",
     "lib": ["es2020", "dom"],
     "skipLibCheck": true,
     "types": ["tslib"]
diff --git a/src/cdk-experimental/selection/row-selection.ts b/src/cdk-experimental/selection/row-selection.ts
@@ -26,7 +26,8 @@ import {CdkSelection} from './selection';
   },
 })
 export class CdkRowSelection<T> {
-  @Input('cdkRowSelectionValue') value: T;
+  // We need an initializer here to avoid a TS error.
+  @Input('cdkRowSelectionValue') value: T = undefined!;
 
   @Input('cdkRowSelectionIndex')
   get index(): number | undefined {
diff --git a/src/cdk/schematics/update-tool/index.ts b/src/cdk/schematics/update-tool/index.ts
@@ -24,7 +24,7 @@ import {createFileSystemCompilerHost} from './utils/virtual-host';
  * the context can provide the necessary specifics to the migrations in a type-safe way.
  */
 export class UpdateProject<Context> {
-  private readonly _typeChecker: ts.TypeChecker = this._program.getTypeChecker();
+  private readonly _typeChecker: ts.TypeChecker;
 
   constructor(
     /** Context provided to all migrations. */
@@ -40,7 +40,9 @@ export class UpdateProject<Context> {
     private _analyzedFiles: Set<WorkspacePath> = new Set(),
     /** Logger used for printing messages. */
     private _logger: UpdateLogger = defaultLogger,
-  ) {}
+  ) {
+    this._typeChecker = this._program.getTypeChecker();
+  }
 
   /**
    * Migrates the project to the specified target version.
diff --git a/src/material-experimental/selection/selection-toggle.ts b/src/material-experimental/selection/selection-toggle.ts
@@ -27,5 +27,5 @@ import {Directive, Input} from '@angular/core';
 })
 export class MatSelectionToggle<T> extends CdkSelectionToggle<T> {
   /** The value that is associated with the toggle */
-  @Input('matSelectionToggleValue') override value: T;
+  @Input('matSelectionToggleValue') override value: T = undefined!;
 }
diff --git a/src/material/chips/chip-grid.ts b/src/material/chips/chip-grid.ts
@@ -261,7 +261,8 @@ export class MatChipGrid
     // indirect descendants if it's left as false.
     descendants: true,
   })
-  override _chips: QueryList<MatChipRow>;
+  // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
+  override _chips: QueryList<MatChipRow> = undefined!;
 
   constructor(
     elementRef: ElementRef,
diff --git a/src/material/chips/chip-listbox.ts b/src/material/chips/chip-listbox.ts
@@ -206,7 +206,8 @@ export class MatChipListbox
     // indirect descendants if it's left as false.
     descendants: true,
   })
-  override _chips: QueryList<MatChipOption>;
+  // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
+  override _chips: QueryList<MatChipOption> = undefined!;
 
   ngAfterContentInit() {
     if (this._pendingInitialValue !== undefined) {
diff --git a/src/material/legacy-tabs/tab.ts b/src/material/legacy-tabs/tab.ts
@@ -49,5 +49,6 @@ export class MatLegacyTab extends _MatTabBase {
    * Template provided in the tab content that will be used if present, used to enable lazy-loading
    */
   @ContentChild(MAT_TAB_CONTENT, {read: TemplateRef, static: true})
-  override _explicitContent: TemplateRef<any>;
+  // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
+  override _explicitContent: TemplateRef<any> = undefined!;
 }
diff --git a/src/material/sidenav/sidenav.ts b/src/material/sidenav/sidenav.ts
@@ -146,7 +146,9 @@ export class MatSidenavContainer extends MatDrawerContainer {
     // indirect descendants if it's left as false.
     descendants: true,
   })
-  override _allDrawers: QueryList<MatSidenav>;
+  // We need an initializer here to avoid a TS error.
+  override _allDrawers: QueryList<MatSidenav> = undefined!;
 
-  @ContentChild(MatSidenavContent) override _content: MatSidenavContent;
+  // We need an initializer here to avoid a TS error.
+  @ContentChild(MatSidenavContent) override _content: MatSidenavContent = undefined!;
 }
diff --git a/src/material/stepper/stepper.ts b/src/material/stepper/stepper.ts
@@ -68,7 +68,8 @@ export class MatStep extends CdkStep implements ErrorStateMatcher, AfterContentI
   private _isSelected = Subscription.EMPTY;
 
   /** Content for step label given by `<ng-template matStepLabel>`. */
-  @ContentChild(MatStepLabel) override stepLabel: MatStepLabel;
+  // We need an initializer here to avoid a TS error.
+  @ContentChild(MatStepLabel) override stepLabel: MatStepLabel = undefined!;
 
   /** Theme color for the particular step. */
   @Input() color: ThemePalette;
@@ -150,10 +151,14 @@ export class MatStep extends CdkStep implements ErrorStateMatcher, AfterContentI
 })
 export class MatStepper extends CdkStepper implements AfterContentInit {
   /** The list of step headers of the steps in the stepper. */
-  @ViewChildren(MatStepHeader) override _stepHeader: QueryList<MatStepHeader>;
+  // We need an initializer here to avoid a TS error.
+  @ViewChildren(MatStepHeader) override _stepHeader: QueryList<MatStepHeader> =
+    undefined as unknown as QueryList<MatStepHeader>;
 
   /** Full list of steps inside the stepper, including inside nested steppers. */
-  @ContentChildren(MatStep, {descendants: true}) override _steps: QueryList<MatStep>;
+  // We need an initializer here to avoid a TS error.
+  @ContentChildren(MatStep, {descendants: true}) override _steps: QueryList<MatStep> =
+    undefined as unknown as QueryList<MatStep>;
 
   /** Steps that belong to the current stepper, excluding ones from nested steppers. */
   override readonly steps: QueryList<MatStep> = new QueryList<MatStep>();
diff --git a/src/material/tabs/tab.ts b/src/material/tabs/tab.ts
@@ -169,7 +169,8 @@ export class MatTab extends _MatTabBase {
    * Template provided in the tab content that will be used if present, used to enable lazy-loading
    */
   @ContentChild(MatTabContent, {read: TemplateRef, static: true})
-  override _explicitContent: TemplateRef<any>;
+  // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
+  override _explicitContent: TemplateRef<any> = undefined!;
 
   /** Content for the tab label given by `<ng-template mat-tab-label>`. */
   @ContentChild(MatTabLabel)
diff --git a/src/material/tree/tree.ts b/src/material/tree/tree.ts
@@ -31,5 +31,6 @@ import {MatTreeNodeOutlet} from './outlet';
 export class MatTree<T, K = T> extends CdkTree<T, K> {
   // Outlets within the tree's template where the dataNodes will be inserted.
   // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
-  @ViewChild(MatTreeNodeOutlet, {static: true}) override _nodeOutlet: MatTreeNodeOutlet;
+  @ViewChild(MatTreeNodeOutlet, {static: true}) override _nodeOutlet: MatTreeNodeOutlet =
+    undefined!;
 }
diff --git a/tools/defaults.bzl b/tools/defaults.bzl
@@ -111,13 +111,13 @@ def ts_library(
         # NodeJS executions, by activating the Bazel NodeJS linker.
         # See: https://github.com/bazelbuild/rules_nodejs/pull/2799.
         package_name = module_name,
-        # For prodmode, the target is set to `ES2020`. `@bazel/typecript` sets `ES2015` by default. Note
+        # For prodmode, the target is set to `ES2022`. `@bazel/typecript` sets `ES2015` by default. Note
         # that this should be in sync with the `ng_module` tsconfig generation to emit proper APF v13.
         # https://github.com/bazelbuild/rules_nodejs/blob/901df3868e3ceda177d3ed181205e8456a5592ea/third_party/github.com/bazelbuild/rules_typescript/internal/common/tsconfig.bzl#L195
-        prodmode_target = prodmode_target if prodmode_target != None else "es2020",
+        prodmode_target = prodmode_target if prodmode_target != None else "es2022",
         # We also set devmode output to the same settings as prodmode as a first step in combining
         # devmode and prodmode output. We will not rely on AMD output anyway due to the linker processing.
-        devmode_target = devmode_target if devmode_target != None else "es2020",
+        devmode_target = devmode_target if devmode_target != None else "es2022",
         devmode_module = devmode_module if devmode_module != None else "esnext",
         tsconfig = tsconfig,
         testonly = testonly,
diff --git a/tools/example-module/example-module.template b/tools/example-module/example-module.template
@@ -29,7 +29,7 @@ export interface NgModuleInfo {
   /**
    * Import specifier that resolves to this module. The specifier is not scoped to
    * `@angular/components-examples` because it's up to the consumer how the module is
-   * imported. For example, in the docs app, modules are lazily imported from `fesm2015/`.
+   * imported. For example, in the docs app, modules are lazily imported from `fesm2022/`.
    */
   importSpecifier: string;
 }
diff --git a/tools/postinstall/patches/@angular+bazel+16.0.0-next.6.patch b/tools/postinstall/patches/@angular+bazel+16.0.0-next.6.patch
@@ -1,16 +1,16 @@
 diff --git a/node_modules/@angular/bazel/src/ng_module/ng_module.bzl b/node_modules/@angular/bazel/src/ng_module/ng_module.bzl
-index d800ffe..9ca5dc9 100755
+index 99d7f6d..3ea60ea 100755
 --- a/node_modules/@angular/bazel/src/ng_module/ng_module.bzl
 +++ b/node_modules/@angular/bazel/src/ng_module/ng_module.bzl
-@@ -19,6 +19,7 @@ load(
+@@ -18,6 +18,7 @@ load(
+     "TsConfigInfo",
      "compile_ts",
      "js_ecma_script_module_info",
-     "js_module_info",
 +    "js_named_module_info",
+     "js_module_info",
      "node_modules_aspect",
      "ts_providers_dict_to_struct",
-     "tsc_wrapped_tsconfig",
-@@ -183,9 +184,9 @@ def _ngc_tsconfig(ctx, files, srcs, **kwargs):
+@@ -151,9 +152,9 @@ def _ngc_tsconfig(ctx, files, srcs, **kwargs):
      is_devmode = "devmode_manifest" in kwargs
      outs = _expected_outs(ctx)
      if is_devmode:
@@ -19,83 +19,61 @@ index d800ffe..9ca5dc9 100755
      else:
 -        expected_outs = outs.closure_js + outs.declarations
 +        expected_outs = outs.closure_js
- 
+
      if not ctx.attr.type_check and ctx.attr.strict_templates:
          fail("Cannot set type_check = False and strict_templates = True for ng_module()")
-@@ -389,11 +390,11 @@ def _compile_action(
- 
+@@ -359,11 +360,11 @@ def _compile_action(
+
  def _prodmode_compile_action(ctx, inputs, outputs, tsconfig_file, node_opts):
      outs = _expected_outs(ctx)
 -    return _compile_action(ctx, inputs, outputs + outs.closure_js + outs.prod_perf_files + outs.declarations, tsconfig_file, node_opts, "prodmode")
 +    return _compile_action(ctx, inputs, outputs + outs.closure_js + outs.prod_perf_files, tsconfig_file, node_opts, "prodmode")
- 
+
  def _devmode_compile_action(ctx, inputs, outputs, tsconfig_file, node_opts):
      outs = _expected_outs(ctx)
 -    compile_action_outputs = outputs + outs.devmode_js + outs.dev_perf_files
 +    compile_action_outputs = outputs + outs.devmode_js + outs.dev_perf_files + outs.declarations
      _compile_action(ctx, inputs, compile_action_outputs, tsconfig_file, node_opts, "devmode")
- 
+
  # Note: We need to define `label` and `srcs_files` as `tsc_wrapped` passes
-@@ -447,7 +448,11 @@ def _ng_module_impl(ctx):
+@@ -417,9 +418,13 @@ def _ng_module_impl(ctx):
      # and issue https://github.com/bazelbuild/rules_nodejs/issues/57 for more details.
      ts_providers["providers"].extend([
          js_module_info(
 -            sources = ts_providers["typescript"]["es6_sources"],
-+            sources = ts_providers["typescript"]["es5_sources"],
-+            deps = ctx.attr.deps,
-+        ),
-+        js_named_module_info(
 +            sources = ts_providers["typescript"]["es5_sources"],
              deps = ctx.attr.deps,
          ),
++        js_named_module_info(
++           sources = ts_providers["typescript"]["es5_sources"],
++           deps = ctx.attr.deps,
++        ),
          js_ecma_script_module_info(
-@@ -465,7 +470,7 @@ def _ng_module_impl(ctx):
+             sources = ts_providers["typescript"]["es6_sources"],
+             deps = ctx.attr.deps,
+@@ -435,7 +440,7 @@ def _ng_module_impl(ctx):
              package_name = ctx.attr.package_name,
              package_path = ctx.attr.package_path,
              path = path,
 -            files = ts_providers["typescript"]["es6_sources"],
 +            files = ts_providers["typescript"]["es5_sources"],
          ))
- 
+
      return ts_providers_dict_to_struct(ts_providers)
-@@ -605,7 +610,6 @@ NG_MODULE_RULE_ATTRS = dict(dict(COMMON_ATTRIBUTES, **NG_MODULE_ATTRIBUTES), **{
-         )
-         """,
-         default = Label(
--            
-             "//typescript:typescript__typings",
-         ),
-     ),
 diff --git a/node_modules/@angular/bazel/src/ngc-wrapped/index.mjs b/node_modules/@angular/bazel/src/ngc-wrapped/index.mjs
-index 354671a..8193af4 100755
+index 8681a4c..e3b497a 100755
 --- a/node_modules/@angular/bazel/src/ngc-wrapped/index.mjs
 +++ b/node_modules/@angular/bazel/src/ngc-wrapped/index.mjs
-@@ -5,6 +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
-  */
-+
- // `tsc-wrapped` helpers are not exposed in the primary `@bazel/concatjs` entry-point.
- import * as ng from '@angular/compiler-cli';
- import { PerfPhase } from '@angular/compiler-cli/private/bazel';
-@@ -13,7 +14,7 @@ import * as fs from 'fs';
+@@ -13,7 +13,7 @@ import * as fs from 'fs';
  import * as path from 'path';
  import * as tsickle from 'tsickle';
  import ts from 'typescript';
 -import { EXT, patchNgHostWithFileNameToModuleName as patchNgHost, relativeToRootDirs } from './utils';
 +import { EXT, patchNgHostWithFileNameToModuleName as patchNgHost, relativeToRootDirs } from './utils.mjs';
- const NGC_GEN_FILES = /^(.*?)\.(ngfactory|ngsummary|ngstyle|shim\.ngstyle)(.*)$/;
  // FIXME: we should be able to add the assets to the tsconfig so FileLoader
  // knows about them
-@@ -21,6 +22,7 @@ const NGC_ASSETS = /\.(css|html|ngsummary\.json)$/;
- const BAZEL_BIN = /\b(blaze|bazel)-out\b.*?\bbin\b/;
- // Note: We compile the content of node_modules with plain ngc command line.
- const ALL_DEPS_COMPILED_WITH_BAZEL = false;
-+
- export async function main(args) {
-     if (tscw.runAsWorker(args)) {
-         await tscw.runWorkerLoop(runOneBuild);
-@@ -368,6 +370,12 @@ function gatherDiagnosticsForInputsOnly(options, bazelOpts, ngProgram) {
+ const NGC_ASSETS = /\.(css|html)$/;
+@@ -351,6 +351,12 @@ function gatherDiagnosticsForInputsOnly(options, bazelOpts, ngProgram) {
      }
      return diagnostics;
  }
diff --git a/tools/postinstall/patches/@bazel+concatjs+5.8.1.patch b/tools/postinstall/patches/@bazel+concatjs+5.8.1.patch
@@ -0,0 +1,13 @@
+diff --git a/node_modules/@bazel/concatjs/internal/build_defs.bzl b/node_modules/@bazel/concatjs/internal/build_defs.bzl
+index 9e5cda6..851c8b7 100755
+--- a/node_modules/@bazel/concatjs/internal/build_defs.bzl
++++ b/node_modules/@bazel/concatjs/internal/build_defs.bzl
+@@ -76,7 +76,7 @@ _TYPESCRIPT_TYPINGS = Label(
+     "//typescript:typescript__typings",
+ )
+ 
+-_TYPESCRIPT_SCRIPT_TARGETS = ["es3", "es5", "es2015", "es2016", "es2017", "es2018", "es2019", "es2020", "esnext"]
++_TYPESCRIPT_SCRIPT_TARGETS = ["es3", "es5", "es2015", "es2016", "es2017", "es2018", "es2019", "es2020", "es2022", "esnext"]
+ _TYPESCRIPT_MODULE_KINDS = ["none", "commonjs", "amd", "umd", "system", "es2015", "esnext"]
+ 
+ _DEVMODE_TARGET_DEFAULT = "es2015"
diff --git a/tools/release-checks/npm-package-output/check-package.mts b/tools/release-checks/npm-package-output/check-package.mts
@@ -13,7 +13,7 @@ import {
 } from './output-validations.mjs';
 
 /** Glob that matches all JavaScript files within a release package. */
-const releaseJsFilesGlob = '+(fesm2015|esm2015|bundles)/**/*.js';
+const releaseJsFilesGlob = '+(fesm2022|esm2022|bundles)/**/*.js';
 
 /** Glob that matches all TypeScript definition files within a release package. */
 const releaseTypeDefinitionsGlob = '**/*.d.ts';
diff --git a/tools/release-checks/npm-package-output/output-validations.mts b/tools/release-checks/npm-package-output/output-validations.mts
@@ -18,7 +18,7 @@ const bazelManifestPath = /(angular_material|external)\//;
  * List of fields which are mandatory in entry-point "package.json" files and refer
  * to files in the release output.
  */
-const packageJsonPathFields = ['module', 'typings', 'fesm2015', 'fesm2020', 'esm2020'];
+const packageJsonPathFields = ['module', 'typings'];
 
 /**
  * Checks the specified JavaScript file and ensures that it does not
diff --git a/tsconfig.json b/tsconfig.json
@@ -19,7 +19,7 @@
     "noImplicitThis": true,
     "skipLibCheck": true,
     "strictBindCallApply": true,
-    "target": "es2020",
+    "target": "es2022",
     "lib": ["es2020", "dom"],
     "types": ["jasmine"],
     "baseUrl": ".",
diff --git a/yarn.lock b/yarn.lock
@@ -227,12 +227,12 @@
   dependencies:
     tslib "^2.3.0"
 
-"@angular/bazel@https://github.com/angular/bazel-builds.git#8b1e899d38c5781662ff01812d5e71aa014b861c":
-  version "16.0.0-next.0"
-  resolved "https://github.com/angular/bazel-builds.git#8b1e899d38c5781662ff01812d5e71aa014b861c"
+"@angular/bazel@https://github.com/angular/bazel-builds.git#bac9c1abe1e6ac1801fbbccb53353a1ed7126469":
+  version "16.0.0-next.6"
+  resolved "https://github.com/angular/bazel-builds.git#bac9c1abe1e6ac1801fbbccb53353a1ed7126469"
   dependencies:
     "@microsoft/api-extractor" "^7.24.2"
-    magic-string "^0.27.0"
+    magic-string "^0.30.0"
     tsickle "^0.46.3"
     tslib "^2.3.0"
 
@@ -11609,7 +11609,7 @@ madge@^4.0.0:
     typescript "^3.9.5"
     walkdir "^0.4.1"
 
-magic-string@0.30.0:
+magic-string@0.30.0, magic-string@^0.30.0:
   version "0.30.0"
   resolved "https://registry.yarnpkg.com/magic-string/-/magic-string-0.30.0.tgz#fd58a4748c5c4547338a424e90fa5dd17f4de529"
   integrity sha512-LA+31JYDJLs82r2ScLrlz1GjSgu66ZV518eyWT+S8VhyQn/JL0u9MeBOvQMGYiPk1DBiSN9DDMOcXvigJZaViQ==
@@ -11623,13 +11623,6 @@ magic-string@^0.25.7:
   dependencies:
     sourcemap-codec "^1.4.8"
 
-magic-string@^0.27.0:
-  version "0.27.0"
-  resolved "https://registry.yarnpkg.com/magic-string/-/magic-string-0.27.0.tgz#e4a3413b4bab6d98d2becffd48b4a257effdbbf3"
-  integrity sha512-8UnnX2PeRAPZuN12svgR9j7M1uWMovg/CEnIwIG0LFkXSJJe4PdfUGiTGl8V9bsBHFUtfVINcSyYxd7q+kx9fA==
-  dependencies:
-    "@jridgewell/sourcemap-codec" "^1.4.13"
-
 make-dir@^1.0.0, make-dir@^1.2.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/make-dir/-/make-dir-1.3.0.tgz#79c1033b80515bd6d24ec9933e860ca75ee27f0c"

Original file line number	Diff line number	Diff line change
`@@ -27,5 +27,5 @@ import {Directive, Input} from '@angular/core';`
`27`	`27`	`})`
`28`	`28`	`export class MatSelectionToggle<T> extends CdkSelectionToggle<T> {`
`29`	`29`	`/** The value that is associated with the toggle */`
`30`		`- @Input('matSelectionToggleValue') override value: T;`
	`30`	`+ @Input('matSelectionToggleValue') override value: T = undefined!;`
`31`	`31`	`}`
Original file line number	Diff line number	Diff line change
`@@ -49,5 +49,6 @@ export class MatLegacyTab extends _MatTabBase {`
`49`	`49`	`* Template provided in the tab content that will be used if present, used to enable lazy-loading`
`50`	`50`	`*/`
`51`	`51`	`@ContentChild(MAT_TAB_CONTENT, {read: TemplateRef, static: true})`
`52`		`- override _explicitContent: TemplateRef<any>;`
	`52`	+ // We need an initializer here to avoid a TS error. The value will be set in `ngAfterViewInit`.
	`53`	`+ override _explicitContent: TemplateRef<any> = undefined!;`
`53`	`54`	`}`