fix: keep the shell directive set by an option or argument handler

.changeset/quiet-files-wait.md

@@ -0,0 +1,5 @@
+---
+'@bomb.sh/tab': patch
+---
+
+fix: keep the shell directive set by an option or argument handler, so handlers can enable file and directory completion

README.md

@@ -353,6 +353,19 @@ my-cli complete -- install --port=""
 :4
 ```
 
+The last line is the shell directive. `:4` (`ShellCompDirectiveNoFileComp`) is the default and stops the shell from falling back to file completion. A handler can set another directive for its completion request, for example to let the shell complete file or directory paths:
+
+```typescript
+import t, { ShellCompDirective } from '@bomb.sh/tab';
+
+devCmd.option('config', 'Config file', () => {
+  t.directive = ShellCompDirective.ShellCompDirectiveDefault; // files
+});
+devCmd.argument('dir', () => {
+  t.directive = ShellCompDirective.ShellCompDirectiveFilterDirs; // directories
+});
+```
+
 ## Documentation
 
 See [bombshell docs](https://bomb.sh/docs/tab/).

src/t.ts

@@ -387,8 +387,6 @@ export class RootCommand extends Command {
   }
 
   private complete(toComplete: string) {
-    this.directive = ShellCompDirective.ShellCompDirectiveNoFileComp;
-
     const seen = new Set<string>();
     this.completions
       .filter((comp) => {
@@ -412,6 +410,7 @@ export class RootCommand extends Command {
 
   parse(args: string[]) {
     this.completions = [];
+    this.directive = ShellCompDirective.ShellCompDirectiveNoFileComp;
 
     const endsWithSpace = args[args.length - 1] === '';
 

tests/directive.test.ts

@@ -0,0 +1,63 @@
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { RootCommand, ShellCompDirective } from '../src/t';
+
+function parse(root: RootCommand, args: string[]): string[] {
+  const log = vi.spyOn(console, 'log').mockImplementation(() => {});
+  root.parse(args);
+  return log.mock.calls.map(([line]) => String(line));
+}
+
+describe('completion directive', () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('disables file completion by default', () => {
+    const root = new RootCommand();
+    root.command('build', 'Build').option('out', 'Output file', () => {});
+
+    expect(parse(root, ['build', '--out', ''])).toEqual([
+      `:${ShellCompDirective.ShellCompDirectiveNoFileComp}`,
+    ]);
+  });
+
+  it('keeps a directive set by an option handler', () => {
+    const root = new RootCommand();
+    root.command('build', 'Build').option('out', 'Output file', () => {
+      root.directive = ShellCompDirective.ShellCompDirectiveDefault;
+    });
+
+    expect(parse(root, ['build', '--out', ''])).toEqual([
+      `:${ShellCompDirective.ShellCompDirectiveDefault}`,
+    ]);
+  });
+
+  it('keeps a directive set by an argument handler', () => {
+    const root = new RootCommand();
+    root.command('serve', 'Serve').argument('dir', () => {
+      root.directive = ShellCompDirective.ShellCompDirectiveFilterDirs;
+    });
+
+    expect(parse(root, ['serve', ''])).toEqual([
+      `:${ShellCompDirective.ShellCompDirectiveFilterDirs}`,
+    ]);
+  });
+
+  it('resets the directive for the next completion request', () => {
+    const root = new RootCommand();
+    const build = root.command('build', 'Build');
+    build.option('out', 'Output file', () => {
+      root.directive = ShellCompDirective.ShellCompDirectiveDefault;
+    });
+    build.option('mode', 'Build mode', (complete) => {
+      complete('production', '');
+    });
+
+    parse(root, ['build', '--out', '']);
+
+    expect(parse(root, ['build', '--mode', ''])).toEqual([
+      'production\t',
+      `:${ShellCompDirective.ShellCompDirectiveNoFileComp}`,
+    ]);
+  });
+});