build: add sourcemaps and add declaration back to tsconfig

package.json

@@ -33,7 +33,7 @@
     "build:js": "rollup --config",
     "build:storybook": "build-storybook -o storybook-static -s src/design-tokens/tier-1-definitions/fonts",
     "build:styles": "postcss \"src/components/**/*.css\" --dir lib/ --base src/ --verbose",
-    "build:types": "tsc --project tsconfig.build.json --declaration --emitDeclarationOnly --declarationDir \"lib/types\"",
+    "build:types": "tsc --project tsconfig.build.json --emitDeclarationOnly",
     "chromatic": "chromatic",
     "copy-fonts-to-lib": "copyfiles -u 3 src/design-tokens/tier-1-definitions/fonts.css src/design-tokens/tier-1-definitions/fonts/**/* lib/tokens",
     "copy-tokens-to-lib": "copyfiles -u 2 src/tokens-dist/**/* lib/tokens",
@@ -64,7 +64,7 @@
     "plop:recipe": "plop recipe",
     "test": "jest",
     "test:ci": "yarn run test --ci --coverage && cat ./coverage/lcov.info | codecov",
-    "types": "tsc"
+    "types": "tsc --noEmit"
   },
   "size-limit": [
     {

rollup.config.mjs

@@ -14,12 +14,14 @@ export default {
       format: 'es',
       preserveModules: true,
       preserveModulesRoot: 'src',
+      sourcemap: true,
     },
     {
       dir: 'lib/cjs',
       format: 'cjs',
       preserveModules: true,
       preserveModulesRoot: 'src',
+      sourcemap: true,
     },
   ],
   /**
@@ -36,6 +38,15 @@ export default {
     }),
     typescript({
       tsconfig: 'tsconfig.build.json',
+      compilerOptions: {
+        /**
+         * Rollup wants declarations in the same directory as the output folder,
+         * but since we ship both cjs and esm in separate folders, this will throw an error.
+         * Declarations are hence built separately using tsc into lib/types
+         */
+        declaration: false,
+        declarationDir: undefined,
+      },
     }),
   ],
 };

src/index.ts

@@ -1,3 +1,4 @@
+// This brings the style tokens that are css custom variables into the built stylesheet so only one stylesheet for EDS has to be imported.
 import './tokens-dist/css/variables.css';
 
 export { default as Accordion } from './components/Accordion';

tsconfig.json

@@ -3,6 +3,8 @@
   "compilerOptions": {
     "allowJs": false,
     "allowSyntheticDefaultImports": true,
+    "declaration": true,
+    "declarationDir": "lib/types",
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
     "jsx": "react",