test(cli): compare rendered command help

packages/coding-agent/test/cli-command-metadata.test.ts

@@ -1,30 +1,53 @@
-import { describe, expect, it } from "bun:test";
-import type { CommandMetadata } from "@oh-my-pi/pi-utils/cli";
+import { describe, expect, it, spyOn } from "bun:test";
+import {
+	type CliConfig,
+	type CommandCtor,
+	type CommandMetadata,
+	renderCommandHelp,
+	renderRootHelp,
+} from "@oh-my-pi/pi-utils/cli";
 import { commands } from "../src/cli-commands";
 
-const METADATA_KEYS = [
-	"description",
-	"hidden",
-	"flags",
-	"args",
-	"examples",
-] as const satisfies readonly (keyof CommandMetadata)[];
+function captureStdout(render: () => void): string {
+	const chunks: string[] = [];
+	const stdoutSpy = spyOn(process.stdout, "write").mockImplementation(chunk => {
+		chunks.push(String(chunk));
+		return true;
+	});
+	try {
+		render();
+	} finally {
+		stdoutSpy.mockRestore();
+	}
+	return chunks.join("");
+}
 
 describe("CLI command help metadata", () => {
-	it("is complete and matches every loaded command", async () => {
+	it("renders the same root help as the loaded command classes", async () => {
+		const metadata = new Map<string, CommandMetadata>();
+		const constructors = new Map<string, CommandCtor>();
 		for (const entry of commands) {
-			const help = entry.help;
-			expect(help, `${entry.name} must provide static help metadata`).toBeDefined();
-			if (!help) continue;
+			expect(entry.help, `${entry.name} must provide static help metadata`).toBeDefined();
+			if (!entry.help) continue;
+			metadata.set(entry.name, entry.help);
+			constructors.set(entry.name, await entry.load());
+		}
 
-			const Command = await entry.load();
-			for (const key of METADATA_KEYS) {
-				if (help[key] !== undefined) {
-					const expected: unknown = help[key];
-					const actual: unknown = Command[key];
-					expect(expected, `${entry.name}.${key} drifted from its command class`).toEqual(actual);
-				}
-			}
+		const base = { bin: "omp", version: "test" };
+		const metadataConfig: CliConfig<CommandMetadata> = { ...base, commands: metadata };
+		const constructorConfig: CliConfig = { ...base, commands: constructors };
+		const metadataRoot = captureStdout(() => renderRootHelp(metadataConfig));
+		const constructorRoot = captureStdout(() => renderRootHelp(constructorConfig));
+		expect(metadataRoot).toBe(constructorRoot);
+
+		const visibleNames = commands.filter(entry => !entry.help?.hidden).map(entry => entry.name);
+		const maxNameLength = Math.max(...visibleNames.map(name => name.length));
+		for (const name of visibleNames) {
+			const Command = constructors.get(name);
+			if (!Command) throw new Error(`Missing loaded command: ${name}`);
+			const commandOutput = captureStdout(() => renderCommandHelp("omp", name, Command));
+			const description = commandOutput.split("\n", 1)[0];
+			expect(metadataRoot).toContain(`  ${name.padEnd(maxNameLength + 2)}${description}`);
 		}
 	});
 });