Test migration to jest by hand

Apparently using regular expressions is way easier.

test/functionName/functionName.test.js

@@ -0,0 +1,19 @@
+const expect = require('expect');
+let output = '';
+const console = {};
+console.debug = (x) => output = x;
+const functionName = fn => (console.debug(fn.name), fn);
+
+  test('functionName is a Function', () => {
+  expect(functionName).toBeInstanceOf(Function);
+});
+  functionName(Math.max);
+  t.equal(output, 'max', 'Works for native functions');
+  function fun(x) {return x;}
+  functionName(fun);
+  t.equal(output, 'fun', 'Works for functions');
+  const fn = x => x;
+  functionName(fn);
+  t.equal(output, 'fn', 'Works for arrow functions');
+  
+