test: add unit tests for getAvx2 Windows ARM64 fallback logic (#154)

* Initial plan

* Add unit tests for getAvx2 function

Co-authored-by: xhyrom <56601352+xhyrom@users.noreply.github.com>

* Consolidate duplicate test assertions in getAvx2 tests

Co-authored-by: xhyrom <56601352+xhyrom@users.noreply.github.com>

* Fix whitespace formatting in test file

Co-authored-by: xhyrom <56601352+xhyrom@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: xhyrom <56601352+xhyrom@users.noreply.github.com>

tests/utils.spec.ts

@@ -0,0 +1,49 @@
+import { describe, expect, it } from "bun:test";
+import { getAvx2 } from "../src/utils";
+
+describe("getAvx2", () => {
+  it("should return false when called with os: 'windows' and arch: 'arm64'", () => {
+    const result = getAvx2("windows", "arm64");
+    expect(result).toBe(false);
+  });
+
+  it("should return false when called with os: 'windows' and arch: 'aarch64'", () => {
+    const result = getAvx2("windows", "aarch64");
+    expect(result).toBe(false);
+  });
+
+  it("should return false when called with os: 'windows', arch: 'arm64', and avx2: true", () => {
+    const result = getAvx2("windows", "arm64", true);
+    expect(result).toBe(false);
+  });
+
+  it("should return false when called with os: 'windows', arch: 'aarch64', and avx2: false", () => {
+    const result = getAvx2("windows", "aarch64", false);
+    expect(result).toBe(false);
+  });
+
+  it("should return the provided avx2 value (true) when specified and not on Windows ARM64", () => {
+    expect(getAvx2("linux", "x64", true)).toBe(true);
+    expect(getAvx2("darwin", "x64", true)).toBe(true);
+    expect(getAvx2("windows", "x64", true)).toBe(true);
+  });
+
+  it("should return the provided avx2 value (false) when specified and not on Windows ARM64", () => {
+    expect(getAvx2("linux", "x64", false)).toBe(false);
+    expect(getAvx2("darwin", "x64", false)).toBe(false);
+    expect(getAvx2("windows", "x64", false)).toBe(false);
+  });
+
+  it("should return true by default when avx2 is not specified and not on Windows ARM64", () => {
+    // x64 architecture on various platforms
+    expect(getAvx2("linux", "x64")).toBe(true);
+    expect(getAvx2("darwin", "x64")).toBe(true);
+    expect(getAvx2("windows", "x64")).toBe(true);
+
+    // ARM architecture on non-Windows platforms
+    expect(getAvx2("linux", "arm64")).toBe(true);
+    expect(getAvx2("linux", "aarch64")).toBe(true);
+    expect(getAvx2("darwin", "arm64")).toBe(true);
+    expect(getAvx2("darwin", "aarch64")).toBe(true);
+  });
+});