cli: add new hidden repo lint command

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/cli/src/commands/index.ts

@@ -42,6 +42,17 @@ export function registerRepoCommand(program: CommanderStatic) {
       'Build all packages, including bundled app and backend packages.',
     )
     .action(lazy(() => import('./repo/build').then(m => m.command)));
+
+  command
+    .command('lint')
+    .description('Lint all packages in the project')
+    .option(
+      '--format <format>',
+      'Lint report output format',
+      'eslint-formatter-friendly',
+    )
+    .option('--fix', 'Attempt to automatically fix violations')
+    .action(lazy(() => import('./repo/lint').then(m => m.command)));
 }
 
 export function registerScriptCommand(program: CommanderStatic) {

packages/cli/src/commands/repo/lint.ts

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2020 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import chalk from 'chalk';
+import { Command } from 'commander';
+import { relative as relativePath } from 'path';
+import { PackageGraph } from '../../lib/monorepo';
+import { runWorkerQueueThreads } from '../../lib/parallel';
+import { paths } from '../../lib/paths';
+
+export async function command(cmd: Command): Promise<void> {
+  const packages = await PackageGraph.listTargetPackages();
+
+  // This formatter uses the cwd to format file paths, so let's have that happen from the root instead
+  if (cmd.format === 'eslint-formatter-friendly') {
+    process.chdir(paths.targetRoot);
+  }
+
+  // Make sure lint output is colored unless the user explicitly disabled it
+  if (!process.env.FORCE_COLOR) {
+    process.env.FORCE_COLOR = '1';
+  }
+
+  const resultsList = await runWorkerQueueThreads({
+    items: packages.map(pkg => ({
+      fullDir: pkg.dir,
+      relativeDir: relativePath(paths.targetRoot, pkg.dir),
+    })),
+    workerData: {
+      fix: Boolean(cmd.fix),
+      format: cmd.format as string | undefined,
+    },
+    workerFactory: async ({ fix, format }) => {
+      const { ESLint } = require('eslint');
+
+      return async ({
+        fullDir,
+        relativeDir,
+      }): Promise<{ relativeDir: string; resultText: string }> => {
+        // Bit of a hack to make file resolutions happen from the correct directory
+        // since some lint rules don't respect the cwd of ESLint
+        process.cwd = () => fullDir;
+
+        const eslint = new ESLint({
+          cwd: fullDir,
+          fix,
+          extensions: ['js', 'jsx', 'ts', 'tsx', 'mjs', 'cjs'],
+        });
+        const formatter = await eslint.loadFormatter(format);
+
+        const results = await eslint.lintFiles(['.']);
+
+        const count = String(results.length).padStart(3);
+        console.log(`Checked ${count} files in ${relativeDir}`);
+
+        if (fix) {
+          await ESLint.outputFixes(results);
+        }
+
+        const resultText = formatter.format(results);
+
+        return { relativeDir, resultText };
+      };
+    },
+  });
+
+  let failed = false;
+  for (const { relativeDir, resultText } of resultsList) {
+    if (resultText) {
+      console.log();
+      console.log(chalk.red(`Lint failed in ${relativeDir}:`));
+      console.log(resultText.trimLeft());
+
+      failed = true;
+    }
+  }
+
+  if (failed) {
+    process.exit(1);
+  }
+}