ebiten: recommend errors.Is instead of comparing the returned value directly

Closes #2152

examples/fullscreen/main.go

@@ -127,7 +127,7 @@ func main() {
 
 	ebiten.SetFullscreen(true)
 	ebiten.SetWindowTitle("Fullscreen (Ebiten Demo)")
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		log.Fatal(err)
 	}
 }

examples/keyboard/keyboard/gen.go

@@ -340,7 +340,7 @@ func (g *game) Layout(outw, outh int) (int, int) {
 
 func main() {
 	g := &game{}
-	if err := ebiten.RunGame(g); err != regularTermination {
+	if err := ebiten.RunGame(g); err != nil && !errors.Is(err, regularTermination) {
 		log.Fatal(err)
 	}
 	if err := outputKeyRectsGo(g.rects); err != nil {

examples/spriteshd/main.go

@@ -202,7 +202,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 func main() {
 	ebiten.SetFullscreen(true)
 	ebiten.SetWindowTitle("Sprites HD (Ebiten Demo)")
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		log.Fatal(err)
 	}
 }

examples/windowclosing/main.go

@@ -62,7 +62,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 func main() {
 	ebiten.SetWindowClosingHandled(true)
 	ebiten.SetWindowTitle("Window Closing (Ebiten Demo)")
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		log.Fatal(err)
 	}
 }

internal/buffered/image_test.go

@@ -73,7 +73,7 @@ func TestMain(m *testing.M) {
 		m:     m,
 		endCh: endCh,
 	}
-	if err := ebiten.RunGame(g); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(g); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 

internal/processtest/testdata/issue1753.go

@@ -108,7 +108,7 @@ func (g *Game) Layout(width, height int) (int, int) {
 }
 
 func main() {
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2079.go

@@ -62,7 +62,7 @@ func (g *Game) Layout(width, height int) (int, int) {
 }
 
 func main() {
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2089.go

@@ -72,7 +72,7 @@ func (g *Game) Layout(width, height int) (int, int) {
 }
 
 func main() {
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2129.go

@@ -64,7 +64,7 @@ func (g *Game) Layout(width, height int) (int, int) {
 }
 
 func main() {
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2154_1.go

@@ -115,7 +115,7 @@ func (g *Game) Layout(width, height int) (int, int) {
 }
 
 func main() {
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2154_2.go

@@ -86,7 +86,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 func main() {
 	ebiten.SetWindowTitle("Test")
 
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2162.go

@@ -59,7 +59,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 
 func main() {
 	// Run a game loop at least for one frame to ensure the shader disposed.
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/processtest/testdata/issue2182.go

@@ -87,7 +87,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 func main() {
 	ebiten.SetWindowTitle("Test")
 
-	if err := ebiten.RunGame(&Game{}); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(&Game{}); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 }

internal/testing/testing.go

@@ -46,7 +46,7 @@ func MainWithRunLoop(m *testing.M) {
 	g := &game{
 		m: m,
 	}
-	if err := ebiten.RunGame(g); err != nil && err != regularTermination {
+	if err := ebiten.RunGame(g); err != nil && !errors.Is(err, regularTermination) {
 		panic(err)
 	}
 	os.Exit(g.code)

run.go

@@ -183,8 +183,10 @@ func (i *imageDumperGame) Layout(outsideWidth, outsideHeight int) (screenWidth,
 // TPS (ticks per second) is 60 by default.
 // This is not related to framerate (display's refresh rate).
 //
-// RunGame returns error when 1) error happens in the underlying graphics driver, 2) audio error happens or
-// 3) f returns error. In the case of 3), RunGame returns the same error.
+// RunGame returns error when 1) an error happens in the underlying graphics driver, 2) an audio error happens
+// or 3) f returns an error. In the case of 3), RunGame returns the same error so far, but it is recommended to
+// use errors.Is when you check the returned error is the error you want, rather than comparing the values
+// with == or != directly.
 //
 // The size unit is device-independent pixel.
 //