[Migration 0-2] Enable ESLint import/no-cycle + boundaries rules (#3349)

Enable ESLint import/no-cycle and architecture boundary rules

Add eslint-plugin-boundaries with element-types matching ARCH_REDESIGN §8,
enable import/no-cycle (error in client/, warn in lib/ and ui/), extend
consistent-default-export-name to client/**/*.tsx, and document §10
types/api.ts enforcement as a follow-up.

eslint.config.mjs

@@ -3,6 +3,7 @@ import jsPlugin from '@eslint/js';
 import nextJsPlugin from '@next/eslint-plugin-next';
 import stylisticPlugin from '@stylistic/eslint-plugin';
 import reactQueryPlugin from '@tanstack/eslint-plugin-query';
+import boundariesPlugin from 'eslint-plugin-boundaries';
 import consistentDefaultExportNamePlugin from 'eslint-plugin-consistent-default-export-name';
 import importPlugin from 'eslint-plugin-import';
 import importHelpersPlugin from 'eslint-plugin-import-helpers';
@@ -57,6 +58,20 @@ const __filename = fileURLToPath(import.meta.url);
 const __dirname = path.dirname(__filename);
 const gitignorePath = path.resolve(__dirname, '.gitignore');
 
+/** @see client/ARCH_REDESIGN.md §8 — dependency layers for migrated code */
+const ARCH_BOUNDARY_ELEMENTS = [
+  { type: 'client-api', pattern: 'client/api/**', mode: 'full' },
+  { type: 'client-slices', pattern: 'client/slices/**', mode: 'full' },
+  { type: 'client-features', pattern: 'client/features/**', mode: 'full' },
+  { type: 'client-shared', pattern: 'client/shared/**', mode: 'full' },
+  { type: 'client-shell', pattern: 'client/shell/**', mode: 'full' },
+  { type: 'configs', pattern: 'configs/**', mode: 'full' },
+  { type: 'toolkit', pattern: 'toolkit/**', mode: 'full' },
+  { type: 'nextjs', pattern: 'nextjs/**', mode: 'full' },
+  { type: 'legacy-lib', pattern: 'lib/**', mode: 'full' },
+  { type: 'legacy-ui', pattern: 'ui/**', mode: 'full' },
+];
+
 /** @type {import('eslint').Linter.Config[]} */
 export default tseslint.config(
   includeIgnoreFile(gitignorePath),
@@ -72,7 +87,12 @@ export default tseslint.config(
 
   { languageOptions: { globals: { ...globals.browser, ...globals.node } } },
 
-  { settings: { react: { version: 'detect' } } },
+  {
+    settings: {
+      react: { version: 'detect' },
+      'boundaries/elements': ARCH_BOUNDARY_ELEMENTS,
+    },
+  },
 
   jsPlugin.configs.recommended,
 
@@ -288,6 +308,100 @@ export default tseslint.config(
     },
   },
 
+  {
+    files: [ 'client/**' ],
+    plugins: {
+      'import': importPlugin,
+    },
+    rules: {
+      'import/no-cycle': [ 'error', { maxDepth: 10 } ],
+    },
+  },
+
+  {
+    files: [ 'lib/**', 'ui/**' ],
+    plugins: {
+      'import': importPlugin,
+    },
+    rules: {
+      'import/no-cycle': 'warn',
+    },
+  },
+
+  /*
+   * ARCH_REDESIGN.md §10 — public type surface: consumers should import slice/feature types only from
+   * `types/api.ts`. eslint-plugin-boundaries can enforce this with `capture` on element patterns and
+   * targeted `disallow` rules; that is left for a follow-up once more slices/features exist under client/.
+   * Type-only cross-layer imports are approximated via per-rule `importKind: 'type'` (v4 has no `allowTypeImports` option).
+   */
+  {
+    files: [
+      'client/**/*.{ts,tsx}',
+      'configs/**/*.{ts,tsx,mjs}',
+    ],
+    plugins: {
+      boundaries: boundariesPlugin,
+    },
+    rules: {
+      'boundaries/element-types': [ 'error', {
+        'default': 'disallow',
+        rules: [
+          {
+            from: 'client-api',
+            allow: [ 'client-shared', 'legacy-lib' ],
+          },
+          {
+            from: 'client-api',
+            allow: [ 'client-slices', 'client-features' ],
+            importKind: 'type',
+          },
+          {
+            from: 'client-slices',
+            allow: [ 'client-api', 'client-shared', 'client-slices', 'legacy-lib', 'legacy-ui', 'toolkit', 'configs' ],
+          },
+          {
+            from: 'client-slices',
+            allow: [ 'client-features' ],
+            importKind: 'type',
+          },
+          {
+            from: 'client-features',
+            allow: [ 'client-api', 'client-shared', 'client-slices', 'client-features', 'legacy-lib', 'legacy-ui', 'toolkit', 'configs' ],
+          },
+          {
+            from: 'client-shared',
+            allow: [ 'client-shared', 'legacy-lib', 'legacy-ui', 'toolkit', 'configs' ],
+          },
+          {
+            from: 'client-shared',
+            allow: [ 'client-slices' ],
+            importKind: 'type',
+          },
+          {
+            from: 'client-shell',
+            allow: [
+              'client-api',
+              'client-slices',
+              'client-features',
+              'client-shared',
+              'client-shell',
+              'legacy-lib',
+              'legacy-ui',
+              'toolkit',
+              'nextjs',
+              'configs',
+            ],
+          },
+          {
+            from: 'configs',
+            // `configs` must not import `client/*`; `lib/*` stays allowed until config-owned types move out of legacy paths
+            allow: [ 'configs', 'legacy-lib' ],
+          },
+        ],
+      } ],
+    },
+  },
+
   {
     plugins: {
       'import-helpers': importHelpersPlugin,
@@ -338,6 +452,7 @@ export default tseslint.config(
     },
     files: [
       'ui/**/[A-Z]*.tsx',
+      'client/**/*.tsx',
     ],
     ignores: [
       '**/*.pw.*',

package.json

@@ -179,6 +179,7 @@
     "dotenv-cli": "^6.0.0",
     "eslint": "9.39.2",
     "eslint-config-next": "16.1.7",
+    "eslint-plugin-boundaries": "^4.2.2",
     "eslint-plugin-consistent-default-export-name": "^0.0.15",
     "eslint-plugin-import": "2.31.0",
     "eslint-plugin-import-helpers": "2.0.1",

pnpm-lock.yaml

@@ -417,6 +417,9 @@ importers:
       eslint-config-next:
         specifier: 16.1.7
         version: 16.1.7(@typescript-eslint/[email protected]([email protected])([email protected]))([email protected])([email protected])
+      eslint-plugin-boundaries:
+        specifier: ^4.2.2
+        version: 4.2.2(@typescript-eslint/[email protected]([email protected])([email protected]))([email protected])
       eslint-plugin-consistent-default-export-name:
         specifier: ^0.0.15
         version: 0.0.15
@@ -8532,6 +8535,33 @@ packages:
       eslint-import-resolver-webpack:
         optional: true
 
+  [email protected]:
+    resolution: {integrity: sha512-rXDXR3h7cs7dy9RNpUlQf80nX31XWJEyGq1tRMo+6GsO5VmTe4UTwtmonAD4ZkAsrfMVDA2wlGJ3790Ys+D49Q==}
+    engines: {node: '>=4'}
+    peerDependencies:
+      '@typescript-eslint/parser': '*'
+      eslint: '*'
+      eslint-import-resolver-node: '*'
+      eslint-import-resolver-typescript: '*'
+      eslint-import-resolver-webpack: '*'
+    peerDependenciesMeta:
+      '@typescript-eslint/parser':
+        optional: true
+      eslint:
+        optional: true
+      eslint-import-resolver-node:
+        optional: true
+      eslint-import-resolver-typescript:
+        optional: true
+      eslint-import-resolver-webpack:
+        optional: true
+
+  [email protected]:
+    resolution: {integrity: sha512-cjwpZqkCXgfz953bc74uDetOtGVxwgMgNZ7hAKi6Oxck+x4oY6Z/9DzgPqAYhtQdSNHFVg+vhft/lSL+snPMQg==}
+    engines: {node: '>=14.0.0'}
+    peerDependencies:
+      eslint: '>=6.0.0'
+
   [email protected]:
     resolution: {integrity: sha512-gqW7dnJbWMxI5H6/Pyz6Sl/vBMwOktePMI2iuuKPb4N82uvemUkfaWhsRZCKndSzpIVaCZ9wdspCVO1tm0wXJQ==}
     engines: {node: '>=0.10.0'}
@@ -10289,6 +10319,10 @@ packages:
   [email protected]:
     resolution: {integrity: sha512-/0LLxhzP0tfiR5hcQebtudP56gUurs2CLkGarnCiB/OqEyUFQ6U3paQi/tgLv0hBJYt2rnr9MNpxz4fiiugstg==}
 
+  [email protected]:
+    resolution: {integrity: sha512-LPP/3KorzCwBxfeUuZmaR6bG2kdeHSbe0P2tY3FLRU4vYrjYz5hI4QZwV0njUx3jeuKe67YukQ1LSPZBKDqO/Q==}
+    engines: {node: '>=8.6'}
+
   [email protected]:
     resolution: {integrity: sha512-PXwfBhYu0hBCPw8Dn0E+WDYb7af3dSLVWKi3HGv84IdF4TyFoC0ysxFd0Goxw7nSv4T/PzEJQxsYsEiFCKo2BA==}
     engines: {node: '>=8.6'}
@@ -25836,6 +25870,29 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
+  [email protected](@typescript-eslint/[email protected]([email protected])([email protected]))([email protected])([email protected]):
+    dependencies:
+      debug: 3.2.7
+    optionalDependencies:
+      '@typescript-eslint/parser': 8.57.1([email protected])([email protected])
+      eslint: 9.39.2
+      eslint-import-resolver-node: 0.3.9
+    transitivePeerDependencies:
+      - supports-color
+
+  [email protected](@typescript-eslint/[email protected]([email protected])([email protected]))([email protected]):
+    dependencies:
+      chalk: 4.1.2
+      eslint: 9.39.2
+      eslint-import-resolver-node: 0.3.9
+      eslint-module-utils: 2.8.1(@typescript-eslint/[email protected]([email protected])([email protected]))([email protected])([email protected])
+      micromatch: 4.0.7
+    transitivePeerDependencies:
+      - '@typescript-eslint/parser'
+      - eslint-import-resolver-typescript
+      - eslint-import-resolver-webpack
+      - supports-color
+
   [email protected]:
     dependencies:
       lodash: 4.17.23
@@ -28037,6 +28094,11 @@ snapshots:
 
   [email protected]: {}
 
+  [email protected]:
+    dependencies:
+      braces: 3.0.3
+      picomatch: 2.3.1
+
   [email protected]:
     dependencies:
       braces: 3.0.3