Prevents a workspace from depending on itself

.yarn/versions/f1299379.yml

@@ -0,0 +1,35 @@
+releases:
+  "@yarnpkg/cli": patch
+  "@yarnpkg/core": patch
+
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-essentials"
+  - "@yarnpkg/plugin-exec"
+  - "@yarnpkg/plugin-file"
+  - "@yarnpkg/plugin-git"
+  - "@yarnpkg/plugin-github"
+  - "@yarnpkg/plugin-http"
+  - "@yarnpkg/plugin-init"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-jsr"
+  - "@yarnpkg/plugin-link"
+  - "@yarnpkg/plugin-nm"
+  - "@yarnpkg/plugin-npm"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnp"
+  - "@yarnpkg/plugin-pnpm"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/doctor"
+  - "@yarnpkg/extensions"
+  - "@yarnpkg/nm"
+  - "@yarnpkg/pnpify"
+  - "@yarnpkg/sdks"

packages/acceptance-tests/pkg-tests-specs/sources/commands/add.test.ts

@@ -561,9 +561,8 @@ describe(`Commands`, () => {
         await run(`add`, `no-deps`);
 
         await expect(xfs.readJsonPromise(ppath.join(path, Filename.manifest))).resolves.toMatchObject({
-          dependencies: {
-            [`no-deps`]: `^2.0.0`,
-          },
+          // Note that Manifest.exportTo disallows depending on self
+          dependencies: {},
         });
       }),
     );

packages/yarnpkg-core/sources/Manifest.ts

@@ -875,6 +875,9 @@ export class Manifest {
       data.dependencies = Object.assign({}, ...structUtils.sortDescriptors(regularDependencies).map(dependency => {
         return {[structUtils.stringifyIdent(dependency)]: dependency.range};
       }));
+      if (data.name && data.dependencies[data.name]) {
+        delete data.dependencies[data.name];
+      }
     } else {
       delete data.dependencies;
     }
@@ -891,6 +894,9 @@ export class Manifest {
       data.devDependencies = Object.assign({}, ...structUtils.sortDescriptors(this.devDependencies.values()).map(dependency => {
         return {[structUtils.stringifyIdent(dependency)]: dependency.range};
       }));
+      if (data.name && data.devDependencies[data.name]) {
+        delete data.devDependencies[data.name];
+      }
     } else {
       delete data.devDependencies;
     }
@@ -899,6 +905,9 @@ export class Manifest {
       data.peerDependencies = Object.assign({}, ...structUtils.sortDescriptors(this.peerDependencies.values()).map(dependency => {
         return {[structUtils.stringifyIdent(dependency)]: dependency.range};
       }));
+      if (data.name && data.peerDependencies[data.name]) {
+        delete data.peerDependencies[data.name];
+      }
     } else {
       delete data.peerDependencies;
     }

packages/yarnpkg-core/tests/Manifest.test.ts

@@ -54,6 +54,24 @@ describe(`Manifest`, () => {
       const manifest = Manifest.fromText(`{ "name": "name", "bin": { "bin1": " ", "bin2": "./bin2.js" } }`);
       expect(manifest.exportTo({}).bin).toEqual({bin2: `./bin2.js`});
     });
+
+    it(`should remove dependency if referencing itself`, () => {
+      const deps = `{ "no-dep": "^1.0.0", "dep": "^1.2.0" }`;
+      const manifest = Manifest.fromText(`
+        { "name": "no-dep", "dependencies": ${deps}, "devDependencies": ${deps}, "peerDependencies": ${deps} }
+      `);
+      expect(manifest.exportTo({})).toMatchObject({
+        dependencies: {
+          dep: `^1.2.0`,
+        },
+        devDependencies: {
+          dep: `^1.2.0`,
+        },
+        peerDependencies: {
+          dep: `^1.2.0`,
+        },
+      });
+    });
   });
 
   describe(`publishConfig`, () => {