From 6ebb5718bd52a3ddc62d4715236851552ff0b697 Mon Sep 17 00:00:00 2001
From: daishi <daishi@axlight.com>
Date: Thu, 1 Jul 2021 14:12:34 +0900
Subject: [PATCH] fix(core): write getter default parameter instead of optional
 parameter

---
 .size-snapshot.json | 12 ++++++------
 src/core/vanilla.ts |  5 ++++-
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/.size-snapshot.json b/.size-snapshot.json
index 8ea14606c3..e1132231a5 100644
--- a/.size-snapshot.json
+++ b/.size-snapshot.json
@@ -1,8 +1,8 @@
 {
   "index.js": {
-    "bundled": 21254,
-    "minified": 10166,
-    "gzipped": 3349,
+    "bundled": 21262,
+    "minified": 10169,
+    "gzipped": 3353,
     "treeshaked": {
       "rollup": {
         "code": 14,
@@ -28,9 +28,9 @@
     }
   },
   "devtools.js": {
-    "bundled": 19114,
-    "minified": 9535,
-    "gzipped": 3277,
+    "bundled": 19122,
+    "minified": 9538,
+    "gzipped": 3281,
     "treeshaked": {
       "rollup": {
         "code": 28,
diff --git a/src/core/vanilla.ts b/src/core/vanilla.ts
index 5e4f0e9ace..d01988e257 100644
--- a/src/core/vanilla.ts
+++ b/src/core/vanilla.ts
@@ -407,7 +407,10 @@ const writeAtomState = <Value, Update>(
     })
     return
   }
-  const writeGetter: WriteGetter = (a: AnyAtom, unstable_promise?: boolean) => {
+  const writeGetter: WriteGetter = (
+    a: AnyAtom,
+    unstable_promise: boolean = false
+  ) => {
     const aState = readAtomState(state, a)
     if (aState.e) {
       throw aState.e // read error