Require CLI filename argument

Author: XhmikosR

bin/cli.js

@@ -10,12 +10,14 @@ program
   .name(name)
   .description(description)
   .version(version)
+  .argument('<filename>', 'the path to file to examine')
   .usage('[options] <filename>')
   .option('-d, --directory <path>', 'location of files of supported filetypes')
   .option('-c, --require-config <path>', 'path to a requirejs config')
   .option('-w, --webpack-config <path>', 'path to a webpack config')
   .option('-t, --ts-config <path>', 'path to a typescript config')
   .option('--list-form', 'output the list form of the tree (one element per line)')
+  .showHelpAfterError()
   .parse();
 
 const cliOptions = program.opts();

test/cli.test.mjs

@@ -0,0 +1,20 @@
+import { strict as assert } from 'node:assert';
+import { spawnSync } from 'node:child_process';
+import path from 'node:path';
+import process from 'node:process';
+import { fileURLToPath } from 'node:url';
+
+const testDir = path.dirname(fileURLToPath(import.meta.url));
+const cliPath = path.resolve(testDir, '..', 'bin', 'cli.js');
+
+describe('dependency-tree CLI', () => {
+  it('prints usage and exits when filename is missing', () => {
+    const result = spawnSync(process.execPath, [cliPath], {
+      encoding: 'utf8'
+    });
+
+    assert.equal(result.status, 1);
+    assert.match(result.stderr, /error: missing required argument 'filename'/);
+    assert.match(result.stderr, /Usage: dependency-tree \[options] <filename>/);
+  });
+});