From 747bceda7b17d65d4c153c887a2878f444d5f526 Mon Sep 17 00:00:00 2001
From: Dmitry Vasilev <dmitry.vasil@gmail.com>
Date: Fri, 2 Dec 2022 08:17:49 +0800
Subject: [PATCH] WIP

---
 src/effects.js          |  4 +++-
 src/eval.js             | 47 ++++++++++++++++++++++++++++-------------
 src/find_definitions.js |  5 +++++
 test/test.js            |  2 +-
 4 files changed, 41 insertions(+), 17 deletions(-)

diff --git a/src/effects.js b/src/effects.js
index df25651..2cd99d1 100644
--- a/src/effects.js
+++ b/src/effects.js
@@ -129,6 +129,7 @@ export const render_initial_state = (ui, state) => {
   ui.editor.switch_session(state.current_module)
 }
 
+// TODO remove async
 export const render_common_side_effects = async (prev, next, command, ui) => {
   if(
     prev.project_dir != next.project_dir 
@@ -188,7 +189,8 @@ export const render_common_side_effects = async (prev, next, command, ui) => {
 
   } else {
 
-    await unwrap_settled_promises(next.calltree)
+    // TODO remove
+    // await unwrap_settled_promises(next.calltree)
 
     if(
       prev.calltree == null
diff --git a/src/eval.js b/src/eval.js
index bed1b17..3b43f21 100644
--- a/src/eval.js
+++ b/src/eval.js
@@ -12,6 +12,8 @@ import {
   map_tree,
 } from './ast_utils.js'
 
+import {has_toplevel_await} from './find_definitions.js'
+
 // TODO: fix error messages. For example, "__fn is not a function"
 
 /*
@@ -255,6 +257,16 @@ const codegen = (node, cxt, parent) => {
   }
 }
 
+/* TODO remove
+const sync_promise = value => {
+  if(value instanceof run_window.Promise.Original) {
+    return value
+  } else {
+    return {is_sync_promise: true, then: fn => sync_promise(fn(value))}
+  }
+}
+*/
+
 export const eval_modules = (
   parse_result,
   external_imports, 
@@ -266,6 +278,8 @@ export const eval_modules = (
 
   // TODO bug if module imported twice, once as external and as regular
 
+  const is_async = has_toplevel_await(parse_result.modules)
+
   const codestring = 
     `
     let children, prev_children
@@ -530,7 +544,7 @@ export const eval_modules = (
       }
     }
 
-    const run = () => {
+    const run = ${is_async ? 'async' : ''} () => {
 
       is_recording_deferred_calls = false
 
@@ -554,18 +568,17 @@ export const eval_modules = (
            module: current_module, 
            id: call_counter++
          }
-         __modules[current_module] = 
-           (() => {
-              try {
-                const __exports = {};
-                ${codegen(parse_result.modules[m], {module: m})};
-                current_call.ok = true
-                return __exports
-              } catch(error) {
-                current_call.ok = false
-                current_call.error = error
-              }
-           })()
+         __modules[current_module] = ${is_async ? 'await (async' : '('} () => {
+            try {
+              const __exports = {};
+              ${codegen(parse_result.modules[m], {module: m})};
+              current_call.ok = true
+              return __exports
+            } catch(error) {
+              current_call.ok = false
+              current_call.error = error
+            }
+         })()
          current_call.children = children
          if(!current_call.ok) {
            is_recording_deferred_calls = true
@@ -639,12 +652,16 @@ export const eval_modules = (
     ? actions.run()
     : calltree_actions.find_call(location)
 
-  return {
+  const make_result = result => ({
     modules: result.modules,
     calltree: assign_code(parse_result.modules, result.calltree),
     call: result.call,
     calltree_actions,
-  }
+  })
+
+  return is_async 
+    ? result.then(make_result)
+    : make_result(result)
 }
 
 // TODO: assign_code: benchmark and use imperative version for perf?
diff --git a/src/find_definitions.js b/src/find_definitions.js
index 5ce41d1..528f488 100644
--- a/src/find_definitions.js
+++ b/src/find_definitions.js
@@ -202,6 +202,11 @@ export const topsort_modules = (modules) => {
   )
 }
 
+export const has_toplevel_await = modules =>
+  Object.values(modules).some(m =>
+    m.children.find(c => c.type == 'unary' && c.operator == 'await' ) != null
+  )
+
 // TODO not implemented
 // TODO detect cycles when loading modules
 export const check_imports = modules => {
diff --git a/test/test.js b/test/test.js
index afaf7d0..3d16136 100644
--- a/test/test.js
+++ b/test/test.js
@@ -2593,7 +2593,7 @@ const y = x()`
     const code = `
       const x = async () => 123
       const y = async () => await x()
-      y()
+      await y()
     `
     const s = test_initial_state(code)
     const move = COMMANDS.move_cursor(s, code.indexOf('await x()')).state