graphicscommand: Add IsShaderAvailable for other packages

internal/graphicscommand/command.go

@@ -22,6 +22,7 @@ import (
 	"github.com/hajimehoshi/ebiten/internal/driver"
 	"github.com/hajimehoshi/ebiten/internal/graphics"
 	"github.com/hajimehoshi/ebiten/internal/shaderir"
+	"github.com/hajimehoshi/ebiten/internal/web"
 )
 
 var theGraphicsDriver driver.Graphics
@@ -39,6 +40,17 @@ func NeedsRestoring() bool {
 	return theGraphicsDriver.NeedsRestoring()
 }
 
+// IsShaderAvailable reports whether shaders are available. This function is only for testing.
+func IsShaderAvailable() bool {
+	if !theGraphicsDriver.IsGL() {
+		return false
+	}
+	if web.IsBrowser() {
+		return false
+	}
+	return true
+}
+
 // command represents a drawing command.
 //
 // A command for drawing that is created when Image functions are called like DrawTriangles,

internal/graphicscommand/export_test.go

@@ -1,19 +0,0 @@
-// 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.
-
-package graphicscommand
-
-func IsGL() bool {
-	return theGraphicsDriver.IsGL()
-}

internal/graphicscommand/image_test.go

@@ -23,7 +23,6 @@ import (
 	. "github.com/hajimehoshi/ebiten/internal/graphicscommand"
 	"github.com/hajimehoshi/ebiten/internal/shaderir"
 	t "github.com/hajimehoshi/ebiten/internal/testing"
-	"github.com/hajimehoshi/ebiten/internal/web"
 )
 
 func TestMain(m *testing.M) {
@@ -82,11 +81,8 @@ func TestReplacePixelsPartAfterDrawTriangles(t *testing.T) {
 }
 
 func TestShader(t *testing.T) {
-	if !IsGL() {
+	if !IsShaderAvailable() {
-		t.Skip("shader is not implemented on non-GL environment")
+		t.Skip("shader is not implemented on this environment")
-	}
-	if web.IsBrowser() {
-		t.Skip("shader is not implemented on browsers")
 	}
 
 	const w, h = 16, 16