feat: detect installed agents

src/agent.ts

@@ -0,0 +1,29 @@
+import { tryGetCommandVersion } from './version.js';
+
+export const agents = ['bun', 'pnpm', 'yarn', 'npm'] as const;
+
+export type AgentName = typeof agents[number];
+
+export interface Agent {
+  name: AgentName;
+  version: string | undefined;
+}
+
+export type AgentMap = Map<AgentName, Agent>;
+
+/**
+ * Detects all (known) agents installed on the system.
+ */
+export async function detectInstalledAgents(): Promise<AgentMap> {
+  const agentsFound: AgentMap = new Map();
+
+  for (const name of agents) {
+    const version = await tryGetCommandVersion(name);
+
+    if (version) {
+      agentsFound.set(name, { name, version });
+    }
+  }
+
+  return agentsFound;
+}

src/index.ts

@@ -1,2 +1,3 @@
 export * from './process.js';
 export * from './version.js';
+export * from './agent.js';

test/agent.test.ts

@@ -0,0 +1,9 @@
+import { expect, it } from 'vitest';
+
+import * as api from '../src/index.js';
+
+it('should find almost one agent (pnpm)', async () => {
+  const agents = await api.detectInstalledAgents();
+
+  expect(agents.has('pnpm')).toBe(true);
+});