test: add unit test for dvisvgm.ts

tests/converters/helpers/converters.ts

@@ -0,0 +1,64 @@
+import type { ExecFileException } from "node:child_process";
+import { expect } from "bun:test";
+import { ConvertFnWithExecFile, ExecFileFn } from "../../../src/converters/types.ts";
+
+export async function runConvertSuccessTest(convertFn: ConvertFnWithExecFile) {
+  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,
+  ) => {
+    callback(null, "Fake stdout", "");
+  };
+
+  const result = await convertFn("input.obj", "obj", "stl", "output.stl", undefined, mockExecFile);
+
+  console.log = originalConsoleLog;
+
+  expect(result).toBe("Done");
+  expect(loggedMessage).toBe("stdout: Fake stdout");
+}
+
+export async function runConvertFailTest(convertFn: ConvertFnWithExecFile) {
+  const mockExecFile: ExecFileFn = (
+    _cmd: string,
+    _args: string[],
+    callback: (err: ExecFileException | null, stdout: string, stderr: string) => void,
+  ) => {
+    callback(new Error("Test error"), "", "");
+  };
+
+  expect(
+    convertFn("input.obj", "obj", "stl", "output.stl", undefined, mockExecFile),
+  ).rejects.toMatch(/error: Error: Test error/);
+}
+
+export async function runConvertLogsStderror(convertFn: ConvertFnWithExecFile) {
+  const originalConsoleError = console.error;
+
+  let loggedMessage = "";
+  console.error = (msg) => {
+    loggedMessage = msg;
+  };
+
+  const mockExecFile = (
+    _cmd: string,
+    _args: string[],
+    cb: (err: Error | null, stdout: string, stderr: string) => void,
+  ) => {
+    cb(null, "", "Fake stderr");
+  };
+
+  await convertFn("file.obj", "obj", "stl", "out.stl", undefined, mockExecFile);
+
+  console.error = originalConsoleError;
+
+  expect(loggedMessage).toBe("stderr: Fake stderr");
+}