fix(pnp): report loaded modules in watch mode (#4934)

Author: merceyz

.gitattributes

@@ -4,11 +4,12 @@
 *                       text=auto eol=lf
 
 # Mark generated files as binary to prevent git from trying to merge them
-/.pnp.*                                               binary linguist-generated
-packages/yarnpkg-pnp/sources/hook.js                  binary linguist-generated
-packages/yarnpkg-core/sources/worker-zip/index.js     binary linguist-generated
-packages/yarnpkg-libzip/sources/libzipAsync.js        binary linguist-generated
-packages/yarnpkg-libzip/sources/libzipSync.js         binary linguist-generated
+/.pnp.*                                                 binary linguist-generated
+packages/yarnpkg-pnp/sources/esm-loader/built-loader.js binary linguist-generated
+packages/yarnpkg-pnp/sources/hook.js                    binary linguist-generated
+packages/yarnpkg-core/sources/worker-zip/index.js       binary linguist-generated
+packages/yarnpkg-libzip/sources/libzipAsync.js          binary linguist-generated
+packages/yarnpkg-libzip/sources/libzipSync.js           binary linguist-generated
 
 # Set the language for these files to json5 to ensure GitHub doesn't show the comments as errors
 /.vscode/*.json         linguist-language=JSON5

.pnp.cjs

@@ -0,0 +1,27 @@
+releases:
+  "@yarnpkg/cli": patch
+  "@yarnpkg/plugin-pnp": patch
+  "@yarnpkg/pnp": patch
+
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-init"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-nm"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnpm"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/core"
+  - "@yarnpkg/doctor"
+  - "@yarnpkg/nm"
+  - "@yarnpkg/pnpify"
+  - "@yarnpkg/sdks"

.yarn/versions/cd516e64.yml

@@ -76,6 +76,7 @@ The following changes only affect people writing Yarn plugins:
 - The patched filesystem now supports `fchown`.
 - PnP now handles private import mappings.
 - Updates the PnP compatibility layer for TypeScript v4.8.4 and v4.9.1-beta.
+- PnP now reports loaded modules when in watch mode.
 
 ### Shell
 

CHANGELOG.md

@@ -1,5 +1,6 @@
+import {VirtualFS, npath}                      from '@yarnpkg/fslib';
 import fs                                      from 'fs';
-import {fileURLToPath}                         from 'url';
+import {fileURLToPath, pathToFileURL}          from 'url';
 
 import {HAS_JSON_IMPORT_ASSERTION_REQUIREMENT} from '../loaderFlags';
 import * as loaderUtils                        from '../loaderUtils';
@@ -31,6 +32,20 @@ export async function load(
     throw err;
   }
 
+  // https://github.com/nodejs/node/pull/44366/files#diff-f6796082f599554ec3a29c47cf026cb24fc5104884f2632e472c05fe622d778bR477-R479
+  if (process.env.WATCH_REPORT_DEPENDENCIES && process.send) {
+    // At the time of writing Node.js reports all loaded URLs itself so
+    // we technically only need to do this for virtual files but in the
+    // event that ever changes we report everything.
+    process.send({
+      'watch:import': pathToFileURL(
+        npath.fromPortablePath(
+          VirtualFS.resolveVirtual(npath.toPortablePath(filePath)),
+        ),
+      ).href,
+    });
+  }
+
   return {
     format,
     source: await fs.promises.readFile(filePath, `utf8`),

packages/yarnpkg-pnp/sources/esm-loader/built-loader.js

@@ -27,6 +27,14 @@ declare global {
   }
 }
 
+// https://github.com/nodejs/node/pull/44366
+const shouldReportRequiredModules = process.env.WATCH_REPORT_DEPENDENCIES;
+function reportModuleToWatchMode(filename: NativePath) {
+  if (shouldReportRequiredModules && process.send) {
+    process.send({'watch:require': npath.fromPortablePath(VirtualFS.resolveVirtual(npath.toPortablePath(filename)))});
+  }
+}
+
 export function applyPatch(pnpapi: PnpApi, opts: ApplyPatchOptions) {
   /**
    * The cache that will be used for all accesses occurring outside of a PnP context.
@@ -167,6 +175,8 @@ export function applyPatch(pnpapi: PnpApi, opts: ApplyPatchOptions) {
     const module = new Module(modulePath, parent ?? undefined) as PatchedModule;
     module.pnpApiPath = moduleApiPath;
 
+    reportModuleToWatchMode(modulePath);
+
     entry.cache[modulePath] = module;
 
     // The main module is exposed as a global variable