build(migrations): skip source map generation (#58299)

alan-agius4 · AndrewKushnir · commit 35954455e2ee · 2024-10-22T07:41:41.000-07:00
Remove the usage of MagicString and the generation of intermediate sourcemaps, as sourcemaps are never included in the schematic bundles. Peparing source maps is a CPU / memory intensive and was causing OoO errors in rollup. PR Close #58299
diff --git a/packages/core/schematics/BUILD.bazel b/packages/core/schematics/BUILD.bazel
@@ -64,6 +64,5 @@ rollup_bundle(
         "//packages/core/schematics/ng-generate/standalone-migration",
         "@npm//@rollup/plugin-commonjs",
         "@npm//@rollup/plugin-node-resolve",
-        "@npm//magic-string",
     ],
 )
diff --git a/packages/core/schematics/rollup.config.js b/packages/core/schematics/rollup.config.js
@@ -7,7 +7,6 @@
  */
 const {nodeResolve} = require('@rollup/plugin-node-resolve');
 const commonjs = require('@rollup/plugin-commonjs');
-const MagicString = require('magic-string');
 
 /** Removed license banners from input files. */
 const stripBannerPlugin = {
@@ -19,15 +18,19 @@ const stripBannerPlugin = {
     }
 
     const [bannerContent] = banner;
-    const magicString = new MagicString(code);
     const pos = code.indexOf(bannerContent);
-    magicString.remove(pos, pos + bannerContent.length).trimStart();
+    if (pos !== -1) {
+      const result = code.slice(0, pos) + code.slice(pos + bannerContent.length);
+
+      return {
+        code: result.trimStart(),
+        map: null,
+      };
+    }
 
     return {
-      code: magicString.toString(),
-      map: magicString.generateMap({
-        hires: true,
-      }),
+      code: code,
+      map: null,
     };
   },
 };

Original file line number	Diff line number	Diff line change
`@@ -64,6 +64,5 @@ rollup_bundle(`
`64`	`64`	`"//packages/core/schematics/ng-generate/standalone-migration",`
`65`	`65`	`"@npm//@rollup/plugin-commonjs",`
`66`	`66`	`"@npm//@rollup/plugin-node-resolve",`
`67`		`- "@npm//magic-string",`
`68`	`67`	`],`
`69`	`68`	`)`