fix: handle more failure cases

packages/build/build/cli.js

@@ -34,7 +34,7 @@ const program = new Command();
 program
   .enablePositionalOptions()
   .name('flecks')
-  .usage('[command] [...]');
+  .usage('<command> [...]');
 // Bootstrap.
 (async () => {
   debugSilly('bootstrapping flecks...');
@@ -43,6 +43,9 @@ program
   // Register commands.
   const commands = await flecks.invokeMergeUniqueAsync('@flecks/build.commands', program);
   const keys = Object.keys(commands).sort();
+  if (0 === keys.length) {
+    program.error('No flecks commands defined! You probably forgot to install packages in this project.');
+  }
   for (let i = 0; i < keys.length; ++i) {
     const {
       action,
@@ -63,5 +66,5 @@ program
     cmd.action(forwardProcessCode(action));
   }
   // Parse commandline.
-  program.parse(process.argv);
+  await program.parseAsync(process.argv);
 })();

packages/build/test/server/cli-no-commands.js

@@ -0,0 +1,30 @@
+import {writeFile} from 'fs/promises';
+import {join} from 'path';
+
+import {createWorkspace} from '@flecks/core/build/testing';
+import {
+  binaryPath,
+  pipesink,
+  processCode,
+  spawnWith,
+} from '@flecks/core/server';
+import {expect} from 'chai';
+
+it('fails predictably if no commands are defined', async () => {
+  const workspace = await createWorkspace();
+  await writeFile(join(workspace, 'package.json'), '{}');
+  const child = spawnWith(
+    [await binaryPath('flecks', '@flecks/build')],
+    {
+      stdio: 'pipe',
+      env: {
+        FLECKS_CORE_ROOT: workspace,
+      },
+    },
+  );
+  const buffer = await pipesink(child.stderr);
+  expect(await processCode(child))
+    .to.equal(1);
+  expect(buffer.toString())
+    .to.contain('No flecks commands defined');
+});