Upgrade to Yarn v3

.github/workflows/build.yml

@@ -5,6 +5,8 @@ on: [push, pull_request]
 jobs:
   build:
     runs-on: ubuntu-latest
+    env:
+      NIX_PATH: nixpkgs=channel:nixpkgs-unstable
     steps:
 
     - name: Checkout
@@ -13,7 +15,7 @@ jobs:
     - name: Setup Node.js
       uses: actions/setup-node@v1
       with:
-        node-version: 10.x
+        node-version: 12.x
 
     - name: Yarn cache
       uses: actions/cache@v2
@@ -59,5 +61,24 @@ jobs:
 
     - name: Test nix-build
       run: nix-build
-      env:
-        NIX_PATH: nixpkgs=channel:nixpkgs-unstable
+
+    # TODO: Check there really is a separate derivation,
+    # and that Yarn actually reuses the build.
+    - name: Test isolated builds
+      run: |
+        # Matches example in  ISOLATED_BUILDS.md
+        echo 'isolatedNixBuilds: ["sqlite3"]' >> .yarnrc.yml
+        cat > default.nix << EOF
+        { pkgs ? import <nixpkgs> { } }:
+
+        pkgs.callPackage ./yarn-project.nix { } {
+          src = ./.;
+          overrideSqlite3Attrs = old: {
+            npm_config_sqlite = "/";  # Don't accidentally use the wrong sqlite.
+            buildInputs = old.buildInputs ++ (with pkgs; [ python3 sqlite ]);
+          };
+        }
+        EOF
+
+        yarn add sqlite3
+        nix-build

.yarnrc.yml

@@ -1 +1 @@
-yarnPath: .yarn/releases/yarn-2.4.1.cjs
+yarnPath: .yarn/releases/yarn-3.0.0.cjs

README.md

@@ -2,7 +2,7 @@
 
 **Upgrading the plugin? See [UPGRADING.md](./UPGRADING.md)**
 
-Generates a [Nix] expression to build a [Yarn] v2 project (not using
+Generates a [Nix] expression to build a [Yarn] v3 project (not using
 zero-install).
 
 - Provides a `yarn` shell alias in the Nix builder — no global Yarn v1 install
@@ -43,7 +43,7 @@ Related projects:
 
 ## Usage
 
-The minimum version of Yarn is 2.2.0. Run the following in your project folder
+The minimum version of Yarn is 3.0.0. Run the following in your project folder
 to check:
 
 ```sh

package.json

@@ -14,42 +14,42 @@
     "@babel/plugin-proposal-decorators": "^7.10.5",
     "@babel/preset-typescript": "^7.10.4",
     "@types/node": "10",
-    "@yarnpkg/cli": "^2.2.0",
-    "@yarnpkg/core": "^2.2.0",
-    "@yarnpkg/fslib": "^2.2.0",
-    "@yarnpkg/parsers": "^2.2.0",
-    "@yarnpkg/plugin-patch": "^2.1.1",
-    "@yarnpkg/plugin-pnp": "^2.2.0",
+    "@yarnpkg/cli": "^3.0.0",
+    "@yarnpkg/core": "^3.0.0",
+    "@yarnpkg/fslib": "^2.5.1",
+    "@yarnpkg/parsers": "^2.4.0",
+    "@yarnpkg/plugin-patch": "^3.0.0",
+    "@yarnpkg/plugin-pnp": "^3.0.0",
     "babel-loader": "^8.1.0",
-    "clipanion": "^2.4.4",
-    "prettier": "2.2.1",
+    "clipanion": "^3.0.0",
+    "prettier": "2.3.2",
     "raw-loader": "^4.0.1",
-    "typescript": "4.2.4",
+    "typescript": "4.3.5",
     "webpack": "^5.35.0",
     "webpack-sources": "^2.2.0"
   },
   "resolutions": {
-    "@yarnpkg/cli": "2.2.0",
-    "@yarnpkg/core": "2.2.0",
-    "@yarnpkg/fslib": "2.2.0",
-    "@yarnpkg/libzip": "2.2.0",
-    "@yarnpkg/parsers": "2.2.0",
-    "@yarnpkg/plugin-compat": "2.1.1",
-    "@yarnpkg/plugin-dlx": "2.1.1",
-    "@yarnpkg/plugin-essentials": "2.2.0",
-    "@yarnpkg/plugin-file": "2.2.0",
-    "@yarnpkg/plugin-git": "2.1.1",
-    "@yarnpkg/plugin-github": "2.1.1",
-    "@yarnpkg/plugin-http": "2.1.1",
-    "@yarnpkg/plugin-init": "2.1.1",
-    "@yarnpkg/plugin-link": "2.1.1",
-    "@yarnpkg/plugin-node-modules": "2.1.1",
-    "@yarnpkg/plugin-npm": "2.2.0",
-    "@yarnpkg/plugin-npm-cli": "2.1.1",
-    "@yarnpkg/plugin-pack": "2.2.0",
-    "@yarnpkg/plugin-patch": "2.1.1",
-    "@yarnpkg/plugin-pnp": "2.2.0",
-    "@yarnpkg/plugin-stage": "2.1.1",
-    "@yarnpkg/shell": "2.2.0"
+    "@yarnpkg/cli": "3.0.1",
+    "@yarnpkg/core": "3.0.0",
+    "@yarnpkg/fslib": "2.5.1",
+    "@yarnpkg/libzip": "2.2.2",
+    "@yarnpkg/parsers": "2.4.0",
+    "@yarnpkg/plugin-compat": "3.0.0",
+    "@yarnpkg/plugin-dlx": "3.0.0",
+    "@yarnpkg/plugin-essentials": "3.0.0",
+    "@yarnpkg/plugin-file": "2.2.1",
+    "@yarnpkg/plugin-git": "2.4.0",
+    "@yarnpkg/plugin-github": "2.2.0",
+    "@yarnpkg/plugin-http": "2.1.3",
+    "@yarnpkg/plugin-init": "3.0.0",
+    "@yarnpkg/plugin-link": "2.1.2",
+    "@yarnpkg/plugin-node-modules": "2.3.0",
+    "@yarnpkg/plugin-npm": "2.5.0",
+    "@yarnpkg/plugin-npm-cli": "3.0.0",
+    "@yarnpkg/plugin-pack": "3.0.0",
+    "@yarnpkg/plugin-patch": "3.0.0",
+    "@yarnpkg/plugin-pnp": "3.0.1",
+    "@yarnpkg/plugin-stage": "3.0.0",
+    "@yarnpkg/shell": "3.0.0"
   }
 }

src/FetchOneCommand.ts

@@ -1,4 +1,4 @@
-import { Command } from "clipanion";
+import { Command, Option } from "clipanion";
 
 import {
   Cache,
@@ -12,10 +12,9 @@ import {
 // Internal command that fetches a single locator.
 // Used from within Nix to build the cache for the project.
 export default class FetchOneCommand extends Command<CommandContext> {
-  @Command.String()
-  locator: string = ``;
+  static paths = [[`nixify`, `fetch-one`]];
+  locator = Option.String();
 
-  @Command.Path(`nixify`, `fetch-one`)
   async execute() {
     const configuration = await Configuration.find(
       this.context.cwd,

src/InjectBuildCommand.ts

@@ -1,4 +1,4 @@
-import { Command } from "clipanion";
+import { Command, Option } from "clipanion";
 import { PortablePath, ppath, xfs } from "@yarnpkg/fslib";
 import { createHash } from "crypto";
 import { parseSyml, stringifySyml } from "@yarnpkg/parsers";
@@ -16,14 +16,11 @@ import {
 
 // Internal command that injects an isolated build inside a Nix build.
 export default class InjectBuildCommand extends Command<CommandContext> {
-  @Command.String()
-  locator: string = ``;
-  @Command.String()
-  source: string = ``;
-  @Command.String()
-  installLocation: string = ``;
+  static paths = [[`nixify`, `inject-build`]];
+  locator = Option.String();
+  source = Option.String();
+  installLocation = Option.String();
 
-  @Command.Path(`nixify`, `inject-build`)
   async execute() {
     const configuration = await Configuration.find(
       this.context.cwd,
@@ -132,12 +129,8 @@ export default class InjectBuildCommand extends Command<CommandContext> {
 
         // Update build state. The way we do this is crude, but we run
         // `yarn install` later, which should clean it up again.
-        const bstatePath: PortablePath = configuration.get(`bstatePath`);
-        const bstate: { [key: string]: string } = xfs.existsSync(bstatePath)
-          ? parseSyml(await xfs.readFilePromise(bstatePath, `utf8`))
-          : {};
-        bstate[pkg.locatorHash] = buildHash;
-        await xfs.writeFilePromise(bstatePath, stringifySyml(bstate));
+        project.storedBuildState.set(pkg.locatorHash, buildHash);
+        await project.persistInstallStateFile();
       }
     );
 

src/InstallBinCommand.ts

@@ -1,4 +1,4 @@
-import { Command } from "clipanion";
+import { Command, Option } from "clipanion";
 import { Filename, npath, ppath, xfs } from "@yarnpkg/fslib";
 import { getPnpPath } from "@yarnpkg/plugin-pnp";
 
@@ -18,10 +18,9 @@ const supportedLinkers = [`pnp`, `node-modules`];
 // Internal command that creates wrappers for binaries.
 // Used inside the Nix install phase.
 export default class InstallBinCommand extends Command<CommandContext> {
-  @Command.String()
-  binDir: string = ``;
+  static paths = [[`nixify`, `install-bin`]];
+  binDir = Option.String();
 
-  @Command.Path(`nixify`, `install-bin`)
   async execute() {
     const configuration = await Configuration.find(
       this.context.cwd,
@@ -49,7 +48,7 @@ export default class InstallBinCommand extends Command<CommandContext> {
         }
 
         const binDir = npath.toPortablePath(this.binDir);
-        const pnpPath = getPnpPath(project).main;
+        const pnpPath = getPnpPath(project).cjs;
         for (const [name, scriptInput] of workspace.manifest.bin) {
           const binPath = ppath.join(binDir, name as Filename);
           const scriptPath = ppath.join(

src/generate.ts

@@ -117,17 +117,13 @@ export default async (project: Project, cache: Cache, report: Report) => {
   cacheEntriesCode += `};`;
 
   // Generate Nix code for isolated builds.
-  const isolatedBuilds: string[] = configuration.get(`isolatedNixBuilds`);
+  const isolatedBuilds = configuration.get(`isolatedNixBuilds`);
   let isolatedPackages = new Set<Package>();
   let isolatedIntegration = [];
   let isolatedCode = [];
 
   const nodeLinker = configuration.get(`nodeLinker`);
   const pnpUnpluggedFolder = configuration.get(`pnpUnpluggedFolder`);
-  const bstatePath: PortablePath = configuration.get(`bstatePath`);
-  const bstate: { [key: string]: string } = xfs.existsSync(bstatePath)
-    ? parseSyml(await xfs.readFilePromise(bstatePath, `utf8`))
-    : {};
 
   const collectTree = (pkg: Package, out: Set<string> = new Set()) => {
     const locatorStr = structUtils.stringifyLocator(pkg);
@@ -184,7 +180,7 @@ export default async (project: Project, cache: Cache, report: Report) => {
     return out;
   };
 
-  for (const locatorHash of Object.keys(bstate)) {
+  for (const locatorHash of project.storedBuildState.keys()) {
     const pkg = project.storedPackages.get(locatorHash as LocatorHash);
     if (!pkg) {
       throw Error(`Assertion failed: The locator should have been registered`);

src/index.ts

@@ -1,10 +1,21 @@
 import { Hooks, Plugin, SettingsType } from "@yarnpkg/core";
+import { PortablePath } from "@yarnpkg/fslib";
 
 import FetchOneCommand from "./FetchOneCommand";
 import InjectBuildCommand from "./InjectBuildCommand";
 import InstallBinCommand from "./InstallBinCommand";
 import generate from "./generate";
 
+declare module "@yarnpkg/core" {
+  interface ConfigurationValueMap {
+    enableNixify: boolean;
+    nixExprPath: PortablePath;
+    generateDefaultNix: boolean;
+    enableNixPreload: boolean;
+    isolatedNixBuilds: string[];
+  }
+}
+
 const plugin: Plugin<Hooks> = {
   commands: [FetchOneCommand, InjectBuildCommand, InstallBinCommand],
   hooks: {

src/tmpl/yarn-project.nix.in

@@ -75,6 +75,8 @@ let
 
       echo '{ "dependencies": { "${pname}": "${version}" } }' > package.json
       install -m 0600 ${lockfile} ./yarn.lock
+      export yarn_global_folder="$TMP"
+      export YARN_ENABLE_IMMUTABLE_INSTALLS=false
       yarn --immutable-cache
     '';
 
@@ -107,6 +109,9 @@ let
       source ${mkCacheBuilderForDrvs (lib.attrValues cacheDrvs)}
       popd > /dev/null
 
+      # Yarn may need a writable home directory.
+      export yarn_global_folder="$TMP"
+
 @@ISOLATED_INTEGRATION@@
 
       # Run normal Yarn install to complete dependency installation.