test: add unit test for libjxl.ts

tests/converters/libjxl.test.ts

@@ -0,0 +1,79 @@
+import type { ExecFileException } from "node:child_process";
+import { beforeEach, expect, test } from "bun:test";
+import { convert } from "../../src/converters/libjxl.ts";
+import { ExecFileFn } from "../../src/converters/types.ts";
+import {
+  runConvertFailTest,
+  runConvertLogsStderror,
+  runConvertSuccessTest,
+} from "./helpers/converters.ts";
+
+let command: string = "";
+
+beforeEach(() => {
+  command = "";
+});
+
+test("convert resolves when execFile succeeds", async () => {
+  await runConvertSuccessTest(convert);
+});
+
+test("convert rejects when execFile fails", async () => {
+  await runConvertFailTest(convert);
+});
+
+test("convert logs stderr when present", async () => {
+  await runConvertLogsStderror(convert);
+});
+
+test("convert uses djxl with input filetype being jxl", async () => {
+  const originalConsoleLog = console.log;
+
+  let loggedMessage = "";
+  console.log = (msg) => {
+    loggedMessage = msg;
+  };
+
+  const mockExecFile: ExecFileFn = (
+    _cmd: string,
+    _args: string[],
+    callback: (err: ExecFileException | null, stdout: string, stderr: string) => void,
+  ) => {
+    command = _cmd;
+    callback(null, "Fake stdout", "");
+  };
+
+  const result = await convert("input.jxl", "jxl", "png", "output.png", undefined, mockExecFile);
+
+  console.log = originalConsoleLog;
+
+  expect(result).toBe("Done");
+  expect(command).toEqual("djxl");
+  expect(loggedMessage).toBe("stdout: Fake stdout");
+});
+
+test("convert uses cjxl with output filetype being jxl", async () => {
+  const originalConsoleLog = console.log;
+
+  let loggedMessage = "";
+  console.log = (msg) => {
+    loggedMessage = msg;
+  };
+
+  const mockExecFile: ExecFileFn = (
+    _cmd: string,
+    _args: string[],
+    callback: (err: ExecFileException | null, stdout: string, stderr: string) => void,
+  ) => {
+    command = _cmd;
+    callback(null, "Fake stdout", "");
+  };
+
+  const result = await convert("input.png", "png", "jxl", "output.jxl", undefined, mockExecFile);
+
+  console.log = originalConsoleLog;
+
+  expect(result).toBe("Done");
+  expect(command).toEqual("cjxl");
+  expect(loggedMessage).toBe("stdout: Fake stdout");
+});