How to fix Angular scss ModuleBuild err

Issue

i am trying to apply a theme to the angular application. I think the src/theme.scss file I created is working properly by itself; but as I import the "~@angular/material/theming", there is an error:

ModuleBuildError: Module build failed (from ./node_modules/sass-loader/dist/cjs.js):
SassError: Can't find stylesheet to import.
  ╷
5 │ @forward '../cdk/a11y/index.import';
  │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵
  node_modules\@angular\material\_theming.scss 5:1  @use
  src\theme.scss 2:1                                root stylesheet
    

I have investigated several posts and I can't get my problem solved.

Here is my src/theme.scss :

@use "~@angular/material/theming" as mat;


@include mat-core();

$app-primary: mat.define-palette(mat.$indigo-palette, 500);
$app-accent: mat.define-palette(mat.$orange-platte, 600);

Here is the /material/_theming.scss:

// Forwards all public API mixins so they can be imported from a single entry point.
// Note that we have to forward the `.import` files for backwards-compatibility with
// projects that don't use Sass modules and include the `mat-`-prefixed mixins.

@forward '../cdk/a11y/index.import';
@forward '../cdk/overlay/index.import';
@forward '../cdk/text-field/index.import';

@forward './core/core-legacy-index';
@forward './autocomplete/autocomplete-legacy-index';
@forward './badge/badge-legacy-index';
@forward './bottom-sheet/bottom-sheet-legacy-index';
@forward './button-toggle/button-toggle-legacy-index';
@forward './button/button-legacy-index';
@forward './card/card-legacy-index';
@forward './checkbox/checkbox-legacy-index';
@forward './chips/chips-legacy-index';
@forward './datepicker/datepicker-legacy-index';
@forward './dialog/dialog-legacy-index';
@forward './divider/divider-legacy-index';
@forward './expansion/expansion-legacy-index';
@forward './form-field/form-field-legacy-index';
@forward './grid-list/grid-list-legacy-index';
@forward './icon/icon-legacy-index';
@forward './input/input-legacy-index';
@forward './list/list-legacy-index';
@forward './menu/menu-legacy-index';
@forward './paginator/paginator-legacy-index';
@forward './progress-bar/progress-bar-legacy-index';
@forward './progress-spinner/progress-spinner-legacy-index';
@forward './radio/radio-legacy-index';
@forward './select/select-legacy-index';
@forward './sidenav/sidenav-legacy-index';
@forward './slide-toggle/slide-toggle-legacy-index';
@forward './slider/slider-legacy-index';
@forward './snack-bar/snack-bar-legacy-index';
@forward './sort/sort-legacy-index';
@forward './stepper/stepper-legacy-index';
@forward './table/table-legacy-index';
@forward './tabs/tabs-legacy-index';
@forward './toolbar/toolbar-legacy-index';
@forward './tooltip/tooltip-legacy-index';
@forward './tree/tree-legacy-index';

and my angular.json:

  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "newProjectRoot": "projects",
  "projects": {
    "TodoNg": {
      "projectType": "application",
      "schematics": {
        "@schematics/angular:application": {
          "strict": true
        }
      },
      "root": "",
      "sourceRoot": "src",
      "prefix": "app",
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-angular:browser",
          "options": {
            "outputPath": "dist/TodoNg",
            "index": "src/index.html",
            "main": "src/main.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.app.json",
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ],
            "styles": [
              "src/styles.css",
              "src/theme.scss"
            ],
            "scripts": []
          },
          "configurations": {
            "production": {
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "500kb",
                  "maximumError": "1mb"
                },
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "2kb",
                  "maximumError": "4kb"
                }
              ],
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.prod.ts"
                }
              ],
              "outputHashing": "all"
            },
            "development": {
              "buildOptimizer": false,
              "optimization": false,
              "vendorChunk": true,
              "extractLicenses": false,
              "sourceMap": true,
              "namedChunks": true
            }
          },
          "defaultConfiguration": "production"
        },
        "serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "configurations": {
            "production": {
              "browserTarget": "TodoNg:build:production"
            },
            "development": {
              "browserTarget": "TodoNg:build:development"
            }
          },
          "defaultConfiguration": "development"
        },
        "extract-i18n": {
          "builder": "@angular-devkit/build-angular:extract-i18n",
          "options": {
            "browserTarget": "TodoNg:build"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "src/test.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.spec.json",
            "karmaConfig": "karma.conf.js",
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ],
            "styles": [
              "src/styles.css",
              "src/theme.scss"
            ],
            "scripts": []
          }
        }
      }
    }
  },
  "defaultProject": "TodoNg"
}

The version of Angular I am using is 12.1.2. Any suggestion how to fix this?

Solution

I just ran into this same issue. It was a version mismatch in my package.json.

I ran an update and all of the @angular packages were versioned "^12.1.4" except @angular/cdk was "^11.x.x" changing it to "@angular/cdk": "^12.1.4" resolved the issue.

Answered By - tuckerjt07