Format Snap manifests with Prettier

.prettierignore

@@ -78,5 +78,3 @@ packages/examples/examples/webpack/index.html
 packages/snaps-execution-environments/lavamoat/**/*.json
 packages/snaps-jest/public
 packages/snaps-simulator/vendor
-
-packages/examples/packages/*/snap.manifest.json

packages/examples/packages/bip32/snap.manifest.json

@@ -24,37 +24,21 @@
     "snap_dialog": {},
     "snap_getBip32Entropy": [
       {
-        "path": [
-          "m",
-          "44'",
-          "0'"
-        ],
+        "path": ["m", "44'", "0'"],
         "curve": "secp256k1"
       },
       {
-        "path": [
-          "m",
-          "44'",
-          "0'"
-        ],
+        "path": ["m", "44'", "0'"],
         "curve": "ed25519"
       },
       {
-        "path": [
-          "m",
-          "44'",
-          "0'"
-        ],
+        "path": ["m", "44'", "0'"],
         "curve": "ed25519Bip32"
       }
     ],
     "snap_getBip32PublicKey": [
       {
-        "path": [
-          "m",
-          "44'",
-          "0'"
-        ],
+        "path": ["m", "44'", "0'"],
         "curve": "secp256k1"
       }
     ]

packages/examples/packages/bip44/snap.manifest.json

@@ -19,9 +19,7 @@
   "initialPermissions": {
     "endowment:rpc": {
       "dapps": true,
-      "allowedOrigins": [
-        "npm:@metamask/json-rpc-example-snap"
-      ]
+      "allowedOrigins": ["npm:@metamask/json-rpc-example-snap"]
     },
     "snap_dialog": {},
     "snap_getBip44Entropy": [

packages/examples/packages/get-file/snap.manifest.json

@@ -15,9 +15,7 @@
         "registry": "https://registry.npmjs.org"
       }
     },
-    "files": [
-      "./files/foo.json"
-    ]
+    "files": ["./files/foo.json"]
   },
   "initialPermissions": {
     "endowment:rpc": {

packages/examples/packages/localization/snap.manifest.json

@@ -15,11 +15,7 @@
         "registry": "https://registry.npmjs.org/"
       }
     },
-    "locales": [
-      "locales/da.json",
-      "locales/en.json",
-      "locales/nl.json"
-    ]
+    "locales": ["locales/da.json", "locales/en.json", "locales/nl.json"]
   },
   "initialPermissions": {
     "endowment:rpc": {

packages/examples/packages/name-lookup/snap.manifest.json

@@ -18,9 +18,7 @@
   },
   "initialPermissions": {
     "endowment:name-lookup": {
-      "chains": [
-        "eip155:1"
-      ]
+      "chains": ["eip155:1"]
     }
   },
   "manifestVersion": "0.1"

packages/snaps-cli/src/commands/manifest/implementation.test.ts

@@ -118,4 +118,63 @@ describe('manifest', () => {
       expect.stringMatching('The snap manifest file has been updated.'),
     );
   });
+
+  it('formats a snap manifest with Prettier', async () => {
+    const error = jest.spyOn(console, 'error').mockImplementation();
+    const log = jest.spyOn(console, 'log').mockImplementation();
+
+    await fs.writeFile(
+      '/snap/snap.manifest.json',
+      JSON.stringify(
+        getSnapManifest({
+          shasum: 'G/W5b2JZVv+epgNX9pkN63X6Lye9EJVJ4NLSgAw/afd=',
+          initialPermissions: {
+            'endowment:name-lookup': {
+              chains: ['eip155:1', 'eip155:2', 'eip155:3'],
+            },
+          },
+        }),
+      ),
+    );
+
+    const spinner = ora();
+    const result = await manifest('/snap/snap.manifest.json', true, spinner);
+    expect(result).toBe(true);
+
+    expect(error).not.toHaveBeenCalled();
+    expect(log).toHaveBeenCalledWith(
+      expect.stringMatching('The snap manifest file has been updated.'),
+    );
+
+    expect(await fs.readFile('/snap/snap.manifest.json', 'utf8'))
+      .toMatchInlineSnapshot(`
+      "{
+        "version": "1.0.0",
+        "description": "The test example snap!",
+        "proposedName": "@metamask/example-snap",
+        "repository": {
+          "type": "git",
+          "url": "https://github.com/MetaMask/example-snap.git"
+        },
+        "source": {
+          "shasum": "d4W7f1lzpVGMj8jjCn1lYhhHmKc/9TSk5QLH5ldKQoI=",
+          "location": {
+            "npm": {
+              "filePath": "dist/bundle.js",
+              "packageName": "@metamask/example-snap",
+              "registry": "https://registry.npmjs.org",
+              "iconPath": "images/icon.svg"
+            }
+          }
+        },
+        "initialPermissions": {
+          "endowment:name-lookup": {
+            "chains": ["eip155:1", "eip155:2", "eip155:3"]
+          }
+        },
+        "manifestVersion": "0.1"
+      }
+      "
+    `);
+  });
 });

packages/snaps-cli/src/commands/manifest/implementation.ts

@@ -1,4 +1,5 @@
 import { checkManifest, indent } from '@metamask/snaps-utils/node';
+import { writeManifest } from '@metamask/snaps-webpack-plugin';
 import { assert } from '@metamask/utils';
 import { red, yellow, green } from 'chalk';
 import type { Ora } from 'ora';
@@ -24,6 +25,7 @@ export async function manifest(
 ): Promise<boolean> {
   const { reports, updated } = await checkManifest(dirname(path), {
     updateAndWriteManifest: write,
+    writeFileFn: writeManifest,
   });
 
   const errors = [];

packages/snaps-webpack-plugin/package.json

@@ -60,6 +60,7 @@
     "@metamask/snaps-sdk": "workspace:^",
     "@metamask/snaps-utils": "workspace:^",
     "@metamask/utils": "^9.2.1",
+    "prettier": "^2.8.8",
     "webpack-sources": "^3.2.3"
   },
   "devDependencies": {
@@ -90,7 +91,6 @@
     "jest-it-up": "^2.0.0",
     "jest-silent-reporter": "^0.6.0",
     "memfs": "^3.4.13",
-    "prettier": "^2.8.8",
     "prettier-plugin-packagejson": "^2.5.2",
     "typescript": "~5.3.3",
     "webpack": "^5.88.0"

packages/snaps-webpack-plugin/src/__fixtures__/.prettierrc.js

@@ -0,0 +1,4 @@
+// Prettier config used for testing.
+module.exports = {
+  tabWidth: 4,
+};

packages/snaps-webpack-plugin/src/index.ts

@@ -1,2 +1,3 @@
+export { writeManifest } from './manifest';
 export { default } from './plugin';
 export type { Options } from './plugin';

packages/snaps-webpack-plugin/src/manifest.test.ts

@@ -0,0 +1,121 @@
+import { getSnapManifest } from '@metamask/snaps-utils/test-utils';
+import { promises as fs } from 'fs';
+import { resolve } from 'path';
+
+import { writeManifest } from './manifest';
+
+jest.mock('fs', () => ({
+  ...jest.requireActual('fs'),
+  promises: {
+    writeFile: jest.fn(),
+  },
+}));
+
+describe('writeManifest', () => {
+  it('formats the manifest with Prettier before writing to disk', async () => {
+    const manifest = JSON.stringify(getSnapManifest());
+    await writeManifest('test.json', manifest);
+
+    expect(jest.mocked(fs.writeFile).mock.calls[0][1]).toMatchInlineSnapshot(`
+      "{
+        "version": "1.0.0",
+        "description": "The test example snap!",
+        "proposedName": "@metamask/example-snap",
+        "repository": {
+          "type": "git",
+          "url": "https://github.com/MetaMask/example-snap.git"
+        },
+        "source": {
+          "shasum": "rNyfINgNh161cBmUop+F7xlE+GSEDZH53Y/HDpGLGGg=",
+          "location": {
+            "npm": {
+              "filePath": "dist/bundle.js",
+              "packageName": "@metamask/example-snap",
+              "registry": "https://registry.npmjs.org",
+              "iconPath": "images/icon.svg"
+            }
+          }
+        },
+        "initialPermissions": {
+          "snap_dialog": {},
+          "endowment:rpc": { "snaps": true, "dapps": false }
+        },
+        "manifestVersion": "0.1"
+      }
+      "
+    `);
+  });
+
+  it('uses a custom Prettier config if found', async () => {
+    const manifest = JSON.stringify(getSnapManifest());
+    await writeManifest(
+      resolve(__dirname, '__fixtures__', 'foo.json'),
+      manifest,
+    );
+
+    expect(jest.mocked(fs.writeFile).mock.calls[0][1]).toMatchInlineSnapshot(`
+      "{
+          "version": "1.0.0",
+          "description": "The test example snap!",
+          "proposedName": "@metamask/example-snap",
+          "repository": {
+              "type": "git",
+              "url": "https://github.com/MetaMask/example-snap.git"
+          },
+          "source": {
+              "shasum": "rNyfINgNh161cBmUop+F7xlE+GSEDZH53Y/HDpGLGGg=",
+              "location": {
+                  "npm": {
+                      "filePath": "dist/bundle.js",
+                      "packageName": "@metamask/example-snap",
+                      "registry": "https://registry.npmjs.org",
+                      "iconPath": "images/icon.svg"
+                  }
+              }
+          },
+          "initialPermissions": {
+              "snap_dialog": {},
+              "endowment:rpc": { "snaps": true, "dapps": false }
+          },
+          "manifestVersion": "0.1"
+      }
+      "
+    `);
+  });
+
+  it('accepts a custom write function', async () => {
+    const fn = jest.fn();
+    const manifest = JSON.stringify(getSnapManifest());
+    await writeManifest('test.json', manifest, fn);
+
+    expect(fn).toHaveBeenCalledTimes(1);
+    expect(fn.mock.calls[0][1]).toMatchInlineSnapshot(`
+      "{
+        "version": "1.0.0",
+        "description": "The test example snap!",
+        "proposedName": "@metamask/example-snap",
+        "repository": {
+          "type": "git",
+          "url": "https://github.com/MetaMask/example-snap.git"
+        },
+        "source": {
+          "shasum": "rNyfINgNh161cBmUop+F7xlE+GSEDZH53Y/HDpGLGGg=",
+          "location": {
+            "npm": {
+              "filePath": "dist/bundle.js",
+              "packageName": "@metamask/example-snap",
+              "registry": "https://registry.npmjs.org",
+              "iconPath": "images/icon.svg"
+            }
+          }
+        },
+        "initialPermissions": {
+          "snap_dialog": {},
+          "endowment:rpc": { "snaps": true, "dapps": false }
+        },
+        "manifestVersion": "0.1"
+      }
+      "
+    `);
+  });
+});

packages/snaps-webpack-plugin/src/manifest.ts

@@ -0,0 +1,32 @@
+import type { WriteFileFunction } from '@metamask/snaps-utils/node';
+import { promises as fs } from 'fs';
+import { format, resolveConfig } from 'prettier';
+
+/**
+ * Format the manifest data with Prettier and write it to disk.
+ *
+ * It uses the Prettier configuration found in the project directory (if any),
+ * or the default Prettier configuration if none is found.
+ *
+ * @param path - The path to write the manifest to.
+ * @param data - The manifest data.
+ * @param writeFileFn - The function to use to write the manifest.
+ * @returns A promise that resolves when the manifest has been written.
+ */
+export async function writeManifest(
+  path: string,
+  data: string,
+  writeFileFn: WriteFileFunction = fs.writeFile,
+) {
+  const config = await resolveConfig(path, {
+    editorconfig: true,
+  });
+
+  const formattedManifest = format(data, {
+    ...config,
+    parser: 'json',
+    filepath: path,
+  });
+
+  await writeFileFn(path, formattedManifest);
+}

packages/snaps-webpack-plugin/src/plugin.test.ts

@@ -15,6 +15,7 @@ import * as pathUtils from 'path';
 import type { Stats, Configuration } from 'webpack';
 import webpack from 'webpack';
 
+import { writeManifest } from './manifest';
 import type { Options } from './plugin';
 import SnapsWebpackPlugin from './plugin';
 
@@ -24,6 +25,10 @@ jest.mock('@metamask/snaps-utils/node', () => ({
   checkManifest: jest.fn(),
 }));
 
+jest.mock('./manifest', () => ({
+  writeManifest: jest.fn(),
+}));
+
 type BundleOptions = {
   code?: string;
   options?: Options;
@@ -215,6 +220,17 @@ describe('SnapsWebpackPlugin', () => {
       sourceCode: expect.any(String),
       writeFileFn: expect.any(Function),
     });
+
+    const writeFileFn = mock.mock.calls[0][1]?.writeFileFn;
+    expect(writeFileFn).toBeDefined();
+    await writeFileFn?.('/snap.manifest.json', 'foo');
+
+    expect(writeManifest).toHaveBeenCalledTimes(1);
+    expect(writeManifest).toHaveBeenCalledWith(
+      '/snap.manifest.json',
+      'foo',
+      expect.any(Function),
+    );
   });
 
   it('does not fix the manifest if configured', async () => {