Add utils unit tests

Author: mayank1513

lib/src/utils.test.ts

@@ -0,0 +1,76 @@
+import { describe, it, expect, beforeAll, afterAll } from "vitest";
+import fs from "node:fs/promises";
+import path from "node:path";
+import os from "node:os";
+import { collectFiles } from "./utils";
+
+const conflictContent = `
+{
+<<<<<<< ours
+  "value": 1
+=======
+  "value": 2
+>>>>>>> theirs
+}
+`;
+
+const cleanContent = `
+{
+  "value": 42
+}
+`;
+
+describe("collectFiles", () => {
+  let tmpDir: string;
+  let conflictedFile: string;
+  let cleanFile: string;
+  let ignoredFile: string;
+
+  beforeAll(async () => {
+    tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), "collect-files-"));
+
+    conflictedFile = path.join(tmpDir, "conflicted.json");
+    cleanFile = path.join(tmpDir, "clean.json");
+    ignoredFile = path.join(tmpDir, "ignored.txt");
+
+    await fs.writeFile(conflictedFile, conflictContent, "utf8");
+    await fs.writeFile(cleanFile, cleanContent, "utf8");
+    await fs.writeFile(ignoredFile, cleanContent, "utf8");
+  });
+
+  afterAll(async () => {
+    await fs.rm(tmpDir, { recursive: true, force: true });
+  });
+
+  it("collects only conflicted files by default", async () => {
+    const files = await collectFiles({
+      root: tmpDir,
+      fileFilter: file => file.endsWith(".json"),
+    });
+
+    expect(files).toContain(conflictedFile);
+    expect(files).not.toContain(cleanFile);
+    expect(files).not.toContain(ignoredFile);
+  });
+
+  it("collects conflicted + clean files when includeNonConflicted is true", async () => {
+    const files = await collectFiles({
+      root: tmpDir,
+      fileFilter: file => file.endsWith(".json"),
+      includeNonConflicted: true,
+    });
+
+    expect(files).toContain(conflictedFile);
+    expect(files).toContain(cleanFile);
+    expect(files).not.toContain(ignoredFile);
+  });
+
+  it("skips files that do not match fileFilter", async () => {
+    const files = await collectFiles({
+      root: tmpDir,
+      fileFilter: file => file.endsWith(".json"),
+    });
+
+    expect(files).not.toContain(ignoredFile);
+  });
+});