feat(tmux): introduce typed tmux command runner abstraction

src/shared/tmux/runner.test.ts

@@ -0,0 +1,127 @@
+/// <reference types="bun-types" />
+
+import { afterAll, describe, expect, test } from "bun:test"
+import { randomUUID } from "node:crypto"
+import fs from "node:fs/promises"
+import os from "node:os"
+import path from "node:path"
+
+import { runTmuxCommand } from "./runner"
+
+const temporaryDirectories: string[] = []
+
+async function createTemporaryDirectory(): Promise<string> {
+	const directoryPath = await fs.mkdtemp(path.join(os.tmpdir(), "tmux-runner-"))
+	temporaryDirectories.push(directoryPath)
+	return directoryPath
+}
+
+async function readInvocationCount(counterFilePath: string): Promise<number> {
+	const count = await fs.readFile(counterFilePath, "utf8")
+	return Number.parseInt(count, 10)
+}
+
+afterAll(async () => {
+	for (const directoryPath of temporaryDirectories) {
+		await fs.rm(directoryPath, { recursive: true, force: true })
+	}
+})
+
+describe("runTmuxCommand", () => {
+	test("#given command exits 0 with stdout #when run #then success true, output and stdout equal trimmed value, stderr empty", async () => {
+		// given
+		const commandArguments = ["-c", "printf '%s\\n' '%42'"]
+
+		// when
+		const result = await runTmuxCommand("sh", commandArguments)
+
+		// then
+		expect(result).toEqual({
+			success: true,
+			output: "%42",
+			stdout: "%42",
+			stderr: "",
+			exitCode: 0,
+		})
+	})
+
+	test("#given command exits 1 with stderr #when run #then success false, stderr populated", async () => {
+		// given
+		const commandArguments = ["-c", "printf '%s\\n' 'some error' >&2; exit 1"]
+
+		// when
+		const result = await runTmuxCommand("sh", commandArguments)
+
+		// then
+		expect(result.success).toBe(false)
+		expect(result.stderr).toBe("some error")
+		expect(result.exitCode).toBe(1)
+	})
+
+	test("#given retry=2 and first exit nonzero #when run #then calls spawn twice before returning failure", async () => {
+		// given
+		const temporaryDirectory = await createTemporaryDirectory()
+		const counterFilePath = path.join(temporaryDirectory, `${randomUUID()}.count`)
+		const commandScript = `counter_file="$1"; count=0; if [ -f "$counter_file" ]; then count=$(cat "$counter_file"); fi; count=$((count + 1)); printf '%s' "$count" > "$counter_file"; printf '%s\\n' 'temporary error' >&2; exit 1`
+
+		// when
+		const result = await runTmuxCommand("sh", ["-c", commandScript, "sh", counterFilePath], { retry: 2 })
+
+		// then
+		expect(result.success).toBe(false)
+		expect(result.stderr).toBe("temporary error")
+		expect(await readInvocationCount(counterFilePath)).toBe(3)
+	})
+
+	test("#given retry=2 and stderr contains 'can't find pane' #when run #then does NOT retry", async () => {
+		// given
+		const temporaryDirectory = await createTemporaryDirectory()
+		const counterFilePath = path.join(temporaryDirectory, `${randomUUID()}.count`)
+		const commandScript = `counter_file="$1"; count=0; if [ -f "$counter_file" ]; then count=$(cat "$counter_file"); fi; count=$((count + 1)); printf '%s' "$count" > "$counter_file"; printf '%s\\n' "can't find pane: %1" >&2; exit 1`
+
+		// when
+		const result = await runTmuxCommand("sh", ["-c", commandScript, "sh", counterFilePath], { retry: 2 })
+
+		// then
+		expect(result.success).toBe(false)
+		expect(result.stderr).toContain("can't find pane")
+		expect(await readInvocationCount(counterFilePath)).toBe(1)
+	})
+
+	test("#given timeoutMs=50 and command sleeps 500ms #when run #then returns timeout failure", async () => {
+		// given
+		const commandArguments = ["-c", "sleep 0.5"]
+
+		// when
+		const result = await runTmuxCommand("sh", commandArguments, { timeoutMs: 50 })
+
+		// then
+		expect(result.success).toBe(false)
+		expect(result.exitCode).toBe(-1)
+		expect(result.stderr).toContain("timeout")
+	})
+
+	test("#given stdout contains trailing newline #when run #then output is trimmed", async () => {
+		// given
+		const commandArguments = ["-c", "printf '%s\\n\\n' '%7'"]
+
+		// when
+		const result = await runTmuxCommand("sh", commandArguments)
+
+		// then
+		expect(result.output).toBe("%7")
+		expect(result.stdout).toBe("%7")
+	})
+
+	test("#given backward-compat consumer destructures {success, output} #when result returned #then both fields present and correct", async () => {
+		// given
+		const commandArguments = ["-c", "printf '%s\\n' '%9'"]
+
+		// when
+		const { success, output } = await runTmuxCommand("sh", commandArguments)
+
+		// then
+		expect(success).toBe(true)
+		expect(output).toBe("%9")
+	})
+})