Fix async assert functions

lib/index.mjs

@@ -8,8 +8,9 @@ function AssertDiff() {
 AssertDiff.options = {strict: false};
 
 Object.keys(assert).forEach(function(k) {
-  AssertDiff[k] = function() {
-    assert[k].apply(assert[k], arguments);
+  let fun = assert[k];
+  AssertDiff[k] = async function() {
+    return fun.apply(fun, arguments);
   };
 });
 

test/example-passing-tests.js

@@ -38,3 +38,36 @@ it('basic derived asserts works', function() {
   assert.equal(3, 3, 'this should not fail')
   assert.object({}, 'this should not fail');
 })
+
+it('async functions', async function() {
+  let a = false;
+  await assert.doesNotReject(function() {
+    return new Promise(function(resolve, reject) {
+      setTimeout(function() {
+        a = true;
+        resolve();
+      })
+    })
+  })
+  assert.ok(a);
+
+  let b = false;
+  await assert.rejects(async function() {
+    return new Promise(function(resolve, reject) {
+      setTimeout(function() {
+        b = true;
+        reject(Error('bad error'))
+      })
+    })
+  });
+  assert.ok(b);
+
+  let c = false;
+  await assert.rejects(new Promise(function(resolve, reject) {
+    setTimeout(function() {
+      c = true;
+      reject(Error('bad error'))
+    })
+  }))
+  assert.ok(c);
+})