Add support for different processor architectures

__tests__/get-arch.test.ts

@@ -0,0 +1,15 @@
+import getArch from '../src/get-arch';
+
+describe('getArch', () => {
+  test('processor architecture', () => {
+    expect(getArch('x64')).toBe('64bit');
+    expect(getArch('arm')).toBe('ARM');
+    expect(getArch('arm64')).toBe('ARM64');
+  });
+
+  test('exception', () => {
+    expect(() => {
+      getArch('mips');
+    }).toThrowError('mips is not supported');
+  });
+});