From 117fd61d27d9b8c63b807ac13fde79ddb9d2fa20 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sat, 30 May 2020 19:24:00 +0900
Subject: [PATCH] restorable: Do not dispose objects when restoring on browsers

This fix suppresses warnings on the Chrome console.
---
 internal/restorable/images.go |  8 ++++++--
 internal/restorable/js.go     | 22 ++++++++++++++++++++++
 internal/restorable/notjs.go  | 19 +++++++++++++++++++
 3 files changed, 47 insertions(+), 2 deletions(-)
 create mode 100644 internal/restorable/js.go
 create mode 100644 internal/restorable/notjs.go

diff --git a/internal/restorable/images.go b/internal/restorable/images.go
index b7d45b69c..4ffaeac41 100644
--- a/internal/restorable/images.go
+++ b/internal/restorable/images.go
@@ -183,7 +183,9 @@ func (i *images) restore() error {
 
 	// Dispose all the shaders ahead of restoring. A current shader ID and a new shader ID can be duplicated.
 	for s := range i.shaders {
-		s.shader.Dispose()
+		if needsDisposingWhenRestoring {
+			s.shader.Dispose()
+		}
 		s.shader = nil
 	}
 	for s := range i.shaders {
@@ -193,7 +195,9 @@ func (i *images) restore() error {
 	// Dispose all the images ahead of restoring. A current texture ID and a new texture ID can be duplicated.
 	// TODO: Write a test to confirm that ID duplication never happens.
 	for i := range i.images {
-		i.image.Dispose()
+		if needsDisposingWhenRestoring {
+			i.image.Dispose()
+		}
 		i.image = nil
 	}
 
diff --git a/internal/restorable/js.go b/internal/restorable/js.go
new file mode 100644
index 000000000..8a14cda21
--- /dev/null
+++ b/internal/restorable/js.go
@@ -0,0 +1,22 @@
+// Copyright 2020 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build js
+
+package restorable
+
+// On browsers, disposing resources is not required since the objects are already managed by JavaScript GC and they
+// are already invalidated. Rather, disposing them when restoring causes warnings on the console.
+
+const needsDisposingWhenRestoring = false
diff --git a/internal/restorable/notjs.go b/internal/restorable/notjs.go
new file mode 100644
index 000000000..b5989c031
--- /dev/null
+++ b/internal/restorable/notjs.go
@@ -0,0 +1,19 @@
+// Copyright 2020 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !js
+
+package restorable
+
+const needsDisposingWhenRestoring = true