cli: add repo test command

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

packages/cli/src/commands/index.ts

@@ -72,6 +72,17 @@ export function registerRepoCommand(program: Command) {
     .action(
       lazy(() => import('./repo/list-deprecations').then(m => m.command)),
     );
+
+  command
+    .command('test')
+    .allowUnknownOption(true) // Allows the command to run, but we still need to parse raw args
+    .option(
+      '--since <ref>',
+      'Only test packages that changed since the specified ref',
+    )
+    .helpOption(', --backstage-cli-help') // Let Jest handle help
+    .description('Run tests, forwarding args to Jest, defaulting to watch mode')
+    .action(lazy(() => import('./repo/test').then(m => m.command)));
 }
 
 export function registerScriptCommand(program: Command) {

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

@@ -0,0 +1,126 @@
+/*
+ * 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 { Command, OptionValues } from 'commander';
+import { PackageGraph } from '../../lib/monorepo';
+import { paths } from '../../lib/paths';
+import { runCheck } from '../../lib/run';
+
+function includesAnyOf(hayStack: string[], ...needles: string[]) {
+  for (const needle of needles) {
+    if (hayStack.includes(needle)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+function removeOptionArg(args: string[], option: string) {
+  let changed = false;
+  do {
+    changed = false;
+
+    const index = args.indexOf(option);
+    if (index >= 0) {
+      changed = true;
+      args.splice(index, 2);
+    }
+    const indexEq = args.findIndex(arg => arg.startsWith(`${option}=`));
+    if (indexEq >= 0) {
+      changed = true;
+      args.splice(indexEq, 1);
+    }
+  } while (changed);
+}
+
+export async function command(opts: OptionValues, cmd: Command): Promise<void> {
+  // all args are forwarded to jest
+  let parent = cmd;
+  while (parent.parent) {
+    parent = parent.parent;
+  }
+  const allArgs = parent.args as string[];
+  const args = allArgs.slice(allArgs.indexOf('test') + 1);
+
+  // Only include our config if caller isn't passing their own config
+  if (!includesAnyOf(args, '-c', '--config')) {
+    args.push('--config', paths.resolveOwn('config/jest.js'));
+  }
+
+  if (!includesAnyOf(args, '--no-passWithNoTests', '--passWithNoTests=false')) {
+    args.push('--passWithNoTests');
+  }
+
+  // Run in watch mode unless in CI, coverage mode, or running all tests
+  if (
+    !process.env.CI &&
+    !args.includes('--coverage') &&
+    // explicitly no watching
+    !includesAnyOf(args, '--no-watch', '--watch=false', '--watchAll=false') &&
+    // already watching
+    !includesAnyOf(args, '--watch', '--watchAll')
+  ) {
+    const isGitRepo = () =>
+      runCheck('git', 'rev-parse', '--is-inside-work-tree');
+    const isMercurialRepo = () => runCheck('hg', '--cwd', '.', 'root');
+
+    if ((await isGitRepo()) || (await isMercurialRepo())) {
+      args.push('--watch');
+    } else {
+      args.push('--watchAll');
+    }
+  }
+
+  if (opts.since) {
+    removeOptionArg(args, '--since');
+  }
+
+  if (opts.since && !args.some(arg => arg.startsWith('--selectProjects'))) {
+    const packages = await PackageGraph.listTargetPackages();
+    const graph = PackageGraph.fromPackages(packages);
+    const changedPackages = await graph.listChangedPackages({
+      ref: opts.since,
+    });
+
+    const packageNames = Array.from(
+      graph.collectPackageNames(
+        changedPackages.map(pkg => pkg.name),
+        pkg => pkg.allLocalDependents.keys(),
+      ),
+    );
+    args.push('--selectProjects', ...packageNames);
+  }
+
+  // This is the only thing that is not implemented by jest.run(), so we do it here instead
+  // https://github.com/facebook/jest/blob/cd8828f7bbec6e55b4df5e41e853a5133c4a3ee1/packages/jest-cli/bin/jest.js#L12
+  if (!process.env.NODE_ENV) {
+    (process.env as any).NODE_ENV = 'test';
+  }
+
+  // This is to have a consistent timezone for when running tests that involve checking
+  // the formatting of date/times.
+  // https://stackoverflow.com/questions/56261381/how-do-i-set-a-timezone-in-my-jest-config
+  if (!process.env.TZ) {
+    process.env.TZ = 'UTC';
+  }
+
+  // This ensures that the process doesn't exit too early before stdout is flushed
+  if (args.includes('--help')) {
+    (process.stdout as any)._handle.setBlocking(true);
+  }
+
+  await require('jest').run(args);
+}

packages/cli/src/commands/test.ts

@@ -78,6 +78,7 @@ export default async (_opts: OptionValues, cmd: Command) => {
     process.env.TZ = 'UTC';
   }
 
+  // This ensures that the process doesn't exit too early before stdout is flushed
   if (args.includes('--help')) {
     (process.stdout as any)._handle.setBlocking(true);
   }