diff --git a/src/cmd.js b/src/cmd.js
index 3c3a767..90ac18b 100644
--- a/src/cmd.js
+++ b/src/cmd.js
@@ -220,15 +220,6 @@ const eval_modules_finished = (state, result, node, toplevel) => {
   if(toplevel) {
     if(node == state.parse_result.modules[root_calltree_module(next)]) {
       active_calltree_node = root_calltree_node(next)
-      return add_frame(
-        default_expand_path(
-          expand_path(
-            next,
-            active_calltree_node
-          )
-        ),
-        active_calltree_node,
-      )
     } else {
       active_calltree_node = null
     }
@@ -244,11 +235,13 @@ const eval_modules_finished = (state, result, node, toplevel) => {
     }
   }
 
+  let result_state
+
   if(active_calltree_node == null) {
     const {node, state: next2} = initial_calltree_node(next)
-    return set_active_calltree_node(next2, null, node)
+    result_state = set_active_calltree_node(next2, null, node)
   } else {
-    return add_frame(
+    result_state = add_frame(
       default_expand_path(
         expand_path(
           next,
@@ -258,6 +251,10 @@ const eval_modules_finished = (state, result, node, toplevel) => {
       active_calltree_node,
     )
   }
+
+  return result_state.eval_modules_state == null
+    ? result_state
+    : {...result_state, eval_modules_state: null}
 }
 
 const input = (state, code, index) => {
diff --git a/src/effects.js b/src/effects.js
index 18f481e..5f27114 100644
--- a/src/effects.js
+++ b/src/effects.js
@@ -8,6 +8,7 @@ import {
 import {current_cursor_position} from './calltree.js'
 import {FLAGS} from './feature_flags.js'
 import {exec, FILES_ROOT} from './index.js'
+// TODO remove
 import {unwrap_settled_promises} from './unwrap_promises.js'
 
 // Imports in the context of `run_window`, so global variables in loaded
diff --git a/src/eval.js b/src/eval.js
index 3b43f21..2cfe0b6 100644
--- a/src/eval.js
+++ b/src/eval.js
@@ -14,6 +14,9 @@ import {
 
 import {has_toplevel_await} from './find_definitions.js'
 
+// external
+import {patch_promise} from './patch_promise.js'
+
 // TODO: fix error messages. For example, "__fn is not a function"
 
 /*
@@ -278,6 +281,13 @@ export const eval_modules = (
 
   // TODO bug if module imported twice, once as external and as regular
 
+  patch_promise(
+    globalThis.run_window 
+    ?? 
+    // Code executed in test env
+    globalThis
+  )
+
   const is_async = has_toplevel_await(parse_result.modules)
 
   const codestring = 
@@ -937,21 +947,35 @@ const do_eval_frame_expr = (node, scope, callsleft) => {
       return {ok: false, children, calls}
     } else {
       const expr = children[0]
-      let value
+      let ok, value, error
       if(node.operator == '!') {
+        ok = true
         value = !expr.result.value
       } else if(node.operator == 'typeof') {
+        ok = true
         value = typeof(expr.result.value)
       } else if(node.operator == '-') {
         value = - expr.result.value
       } else if(node.operator == 'await') {
-        log('expr', expr.result.value.status)
-        value = expr.result.value
-        //throw new Error('not implemented')
+        const run_window = globalThis.run_window ?? globalThis
+        if(expr.result.value instanceof run_window.Promise.Original) {
+          const status = expr.result.value.status
+          if(status == null) {
+            // Promise must be already resolved
+            throw new Error('illegal state')
+          } else {
+            ok = status.ok
+            error = status.error
+            value = status.value
+          }
+        } else {
+          ok = true
+          value = expr.result.value
+        }
       } else {
         throw new Error('unknown op')
       }
-      return {ok: true, children, calls, value}
+      return {ok, children, calls, value, error}
     }
   } else if(node.type == 'binary' && !['&&', '||', '??'].includes(node.operator)){
 
diff --git a/src/globals.js b/src/globals.js
index a2fea60..c9b2c2e 100644
--- a/src/globals.js
+++ b/src/globals.js
@@ -1,6 +1,6 @@
 export const globals = new Set([
   'globalThis',
-  // TODO Promise,
+  'Promise',
   // TODO Symbol
   'URL',
   'Set', 
diff --git a/src/patch_promise.js b/src/patch_promise.js
index 1c1a4b6..b2bd462 100644
--- a/src/patch_promise.js
+++ b/src/patch_promise.js
@@ -1,8 +1,8 @@
 export const patch_promise = window => {
 
-  // TODO check that it is not already patched
   if(window.Promise.Original != null) {
-    throw new Error('already patched')
+    // already patched
+    return
   }
 
   class PromiseWithStatus extends Promise {
diff --git a/test/test.js b/test/test.js
index 3a53335..ca523e3 100644
--- a/test/test.js
+++ b/test/test.js
@@ -15,10 +15,10 @@ import {
   test_only,
   assert_equal, 
   stringify, 
-  assert_code_evals_to,
-  assert_code_error,
+  assert_code_evals_to, assert_code_evals_to_async,
+  assert_code_error, assert_code_error_async,
   parse_modules,
-  test_initial_state,
+  test_initial_state, test_initial_state_async,
   test_deferred_calls_state,
   print_debug_ct_node,
 } from './utils.js'
@@ -2589,15 +2589,80 @@ const y = x()`
     assert_equal(get_deferred_calls(result), null)
   }),
 
-  test('async/await', () => {
-    const code = `
-      const x = async () => 123
-      const y = async () => await x()
-      await y()
-    `
-    const s = test_initial_state(code)
-    const move = COMMANDS.move_cursor(s, code.indexOf('await x()')).state
-    log('m', root_calltree_node(move).children[0].children[0].value)
-    //log(s.parse_result.modules[''])
+  test('async/await return from async function', async () => {
+    await assert_code_evals_to_async(
+      `
+        const x = async () => 123
+        const y = async () => await x()
+        await y()
+      `,
+      123
+    )
   }),
+
+  test('async/await await Promise', async () => {
+    await assert_code_evals_to_async(
+      `
+        await Promise.resolve(123)
+      `,
+      123
+    )
+  }),
+
+  test('async/await await Promise returned from async function', async () => {
+    await assert_code_evals_to_async(
+      `
+        const x = async () => {
+          return Promise.resolve(123)
+        }
+        await x()
+      `,
+      123
+    )
+  }),
+
+  test('async/await throw from async function', async () => {
+    await assert_code_error_async(
+      `
+        const x = async () => { throw 'boom' }
+        await x()
+      `,
+      'boom'
+    )
+  }),
+
+  test('async/await await rejected Promise', async () => {
+    await assert_code_error_async(
+      `
+        await Promise.reject('boom')
+      `,
+      'boom'
+    )
+  }),
+
+  test('async/await await rejected Promise', async () => {
+    await assert_code_error_async(
+      `
+        await Promise.reject('boom')
+      `,
+      'boom'
+    )
+  }),
+
+  test('async/await await rejected Promise returned from async', async () => {
+    await assert_code_error_async(
+      `
+        const x = async () => Promise.reject('boom')
+        await x()
+      `,
+      'boom'
+    )
+  }),
+
+    // TODO
+    //assert_equal('s', active_frame
+    //const result = await s.eval_modules_state
+    //const move = COMMANDS.move_cursor(s, code.indexOf('await x()')).state
+    //log('m', root_calltree_node(move).children[0].children[0].value)
+    //log(s.parse_result.modules[''])
 ]
diff --git a/test/utils.js b/test/utils.js
index 796e5d9..693cf5b 100644
--- a/test/utils.js
+++ b/test/utils.js
@@ -1,12 +1,8 @@
 import {parse, print_debug_node, load_modules} from '../src/parse_js.js'
 import {eval_tree, eval_frame} from '../src/eval.js'
+import {active_frame} from '../src/calltree.js'
 import {COMMANDS} from '../src/cmd.js'
 
-// external
-import {patch_promise} from '../src/patch_promise.js'
-
-patch_promise(globalThis)
-
 Object.assign(globalThis, {log: console.log})
 
 export const parse_modules = (entry, modules) => 
@@ -32,6 +28,22 @@ export const assert_code_error = (codestring, error) => {
   assert_equal(result.error, error)
 }
 
+export const assert_code_evals_to_async = async (codestring, expected) => {
+  const s = await test_initial_state_async(codestring)
+  const frame = active_frame(s)
+  const result = frame.children[frame.children.length - 1].result
+  assert_equal(result.ok, true)
+  assert_equal(result.value, expected)
+}
+
+export const assert_code_error_async = async (codestring, error) => {
+  const s = await test_initial_state_async(codestring)
+  const frame = active_frame(s)
+  const result = frame.children[frame.children.length - 1].result
+  assert_equal(result.ok, false)
+  assert_equal(result.error, error)
+}
+
 export const test_initial_state = (code, state) => {
   return COMMANDS.open_run_window(
     COMMANDS.get_initial_state(
@@ -45,6 +57,18 @@ export const test_initial_state = (code, state) => {
   )
 }
 
+export const test_initial_state_async = async code => {
+  const s = test_initial_state(code)
+  assert_equal(s.eval_modules_state != null, true)
+  const result = await s.eval_modules_state.promise
+  return COMMANDS.eval_modules_finished(
+    s, 
+    result, 
+    s.eval_modules_state.node, 
+    s.eval_modules_state.toplevel
+  )
+}
+
 export const test_deferred_calls_state = code => {
   const {get_deferred_call, on_deferred_call} = (new Function(`
     let call, calltree_changed_token
@@ -119,10 +143,13 @@ export const test_only = (message, t) => test(message, t, true)
 // Wrap to Function constructor to hide from calltree view
 // TODO in calltree view, hide fn which has special flag set (see
 // filter_calltree)
-export const run = Object.defineProperty(new Function('tests', `
-    const run_test = t => {
+
+const AsyncFunction = new Function(`return (async () => {}).constructor`)()
+
+export const run = Object.defineProperty(new AsyncFunction('tests', `
+    const run_test = async t => {
       try {
-        t.test()
+        await t.test()
       } catch(e) {
         if(globalThis.process != null) {
           // In node.js runner, fail fast
@@ -142,12 +169,13 @@ export const run = Object.defineProperty(new Function('tests', `
       const only = tests.find(t => t.only)
       const tests_to_run = only == null ? tests : [only]
 
-      // Exec each test. After all tests are done, we rethrow first failer if
+      // Exec each test. After all tests are done, we rethrow first error if
       // any. So we will mark root calltree node if one of tests failed
-      const failure = tests_to_run.reduce(
-        (failure, t) => {
-          const next_failure = run_test(t)
-          return failure ?? next_failure
+      const failure = await tests_to_run.reduce(
+        async (failureP, t) => {
+          const failure = await failureP
+          const next_failure = await run_test(t)
+          return (await failure) ?? next_failure
         },
         null
       )
@@ -165,7 +193,7 @@ export const run = Object.defineProperty(new Function('tests', `
       if(test == null) {
         throw new Error('test not found')
       } else {
-        run_test(test)
+        await run_test(test)
         if(globalThis.process != null) {
           console.log('Ok')
         }
diff --git a/x.js b/x.js
index 1088838..7a2fe71 100644
--- a/x.js
+++ b/x.js
@@ -1,17 +1,31 @@
-/*
-const delay = new Promise(resolve => {
+const delay = () => new Promise(resolve => {
   setTimeout(resolve, 1000)
 })
+
+await [1,2,3,4,5].reduce(
+  async (acc, x) => {
+    console.log('wait')
+    await acc
+    await delay()
+    console.log('wait finish')
+  },
+  Promise.resolve(),
+)
+
+
+/*
 await delay
 console.log('x')
 export const x = 1
 */
 
+/*
 const p = {then: y => y(3)}
 
 async function test() {
   return await p
 }
+*/
 
   // TODO remove
   //const x = new Promise((resolve, reject) => resolve(10))
@@ -26,4 +40,4 @@ async function test() {
   //x.then(() => {
   //  console.log('x', x.status)
   //})
-console.log(await test())
+//console.log(await test())