Merge pull request #4 from inkyblackness/feature/linter-action

Feature/linter action

Author: dertseha

.github/workflows/golangci-lint.yaml

@@ -0,0 +1,17 @@
+name: golangci-lint
+on: [push, pull_request]
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install libraries
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y mesa-utils mesa-common-dev libsdl2-dev libglfw3-dev
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v1
+        with:
+          version: v1.27

.golangci.yml

@@ -14,8 +14,8 @@ linters:
     - goimports # disabled because of so many false-positives with "imgui-go"
     - gosec
     - maligned
+    - gomnd # disabled as most OpenGL stuff are direct constants.
     - funlen # disabled because of example code. While people will probably tend to duplicate this, they'll handle it on their own.
-    - godox # for the deliberate TODO tags
     - wsl # this one became too pedantic and with a different style than I would.
 
 issues:
@@ -29,12 +29,3 @@ issues:
 linters-settings:
   lll:
     line-length: 160
-
-service:
-  golangci-lint-version: 1.21.x
-  prepare:
-    - apt-get update && apt-get install -y mesa-utils mesa-common-dev libsdl2-dev libglfw3-dev
-    # the following a fix as per https://github.com/golangci/golangci/issues/29#issuecomment-460649402 -- missing vendor libraries
-    - GO111MODULE=on go mod vendor
-    # the following a fix as per https://github.com/esimov/diagram/issues/7#issuecomment-443186458 -- glfw library broken through vendoring
-    - GO111MODULE=off go get -u github.com/go-gl/glfw/v3.2/glfw/glfw; cp -R $GOPATH/src/github.com/go-gl/glfw/v3.2/glfw/glfw vendor/github.com/go-gl/glfw/v3.2/glfw/glfw

README.md

@@ -1,7 +1,7 @@
 # Examples of Dear ImGui for Go
 
 [![Go Report Card](https://goreportcard.com/badge/github.com/inkyblackness/imgui-go-examples)](https://goreportcard.com/report/github.com/inkyblackness/imgui-go-examples)
-[![GolangCI](https://golangci.com/badges/github.com/inkyblackness/imgui-go-examples.svg)](https://golangci.com)
+[![Lint Status](https://github.com/inkyblackness/imgui-go-examples/workflows/golangci-lint/badge.svg)](https://github.com/inkyblackness/imgui-go-examples/actions)
 
 This project contains a set of [Go](https://www.golang.org) examples for [imgui-go](https://github.com/inkyblackness/imgui-go), which is a wrapper for [**Dear ImGui**](https://github.com/ocornut/imgui).
 

internal/demo/Run.go

@@ -47,14 +47,19 @@ type Renderer interface {
 	Render(displaySize [2]float32, framebufferSize [2]float32, drawData imgui.DrawData)
 }
 
+const (
+	millisPerSecond = 1000
+	sleepDuration   = time.Millisecond * 25
+)
+
 // Run implements the main program loop of the demo. It returns when the platform signals to stop.
 // This demo application shows some basic features of ImGui, as well as exposing the standard demo window.
 func Run(p Platform, r Renderer) {
 	imgui.CurrentIO().SetClipboard(clipboard{platform: p})
 
 	showDemoWindow := false
 	clearColor := [3]float32{0.0, 0.0, 0.0}
-	f := float32(0.0)
+	f := float32(0)
 	counter := 0
 	showAnotherWindow := false
 
@@ -83,7 +88,7 @@ func Run(p Platform, r Renderer) {
 			imgui.Text(fmt.Sprintf("counter = %d", counter))
 
 			imgui.Text(fmt.Sprintf("Application average %.3f ms/frame (%.1f FPS)",
-				1000.0/imgui.CurrentIO().Framerate(), imgui.CurrentIO().Framerate()))
+				millisPerSecond/imgui.CurrentIO().Framerate(), imgui.CurrentIO().Framerate()))
 		}
 
 		// 2. Show another simple window. In most cases you will use an explicit Begin/End pair to name your windows.
@@ -102,7 +107,9 @@ func Run(p Platform, r Renderer) {
 		if showDemoWindow {
 			// Normally user code doesn't need/want to call this because positions are saved in .ini file anyway.
 			// Here we just want to make the demo initial state a bit more friendly!
-			imgui.SetNextWindowPosV(imgui.Vec2{X: 650, Y: 20}, imgui.ConditionFirstUseEver, imgui.Vec2{})
+			const demoX = 650
+			const demoY = 20
+			imgui.SetNextWindowPosV(imgui.Vec2{X: demoX, Y: demoY}, imgui.ConditionFirstUseEver, imgui.Vec2{})
 
 			imgui.ShowDemoWindow(&showDemoWindow)
 		}
@@ -118,6 +125,6 @@ func Run(p Platform, r Renderer) {
 		p.PostRender()
 
 		// sleep to avoid 100% CPU usage for this demo
-		<-time.After(time.Millisecond * 25)
+		<-time.After(sleepDuration)
 	}
 }

internal/platforms/constants.go

@@ -0,0 +1,11 @@
+package platforms
+
+const (
+	windowWidth  = 1280
+	windowHeight = 720
+
+	mouseButtonPrimary   = 0
+	mouseButtonSecondary = 1
+	mouseButtonTertiary  = 2
+	mouseButtonCount     = 3
+)

internal/platforms/errors.go

@@ -0,0 +1,14 @@
+package platforms
+
+// StringError describes a basic error with static information.
+type StringError string
+
+// Error returns the string itself.
+func (err StringError) Error() string {
+	return string(err)
+}
+
+const (
+	// ErrUnsupportedClientAPI is used in case the API is not available by the platform.
+	ErrUnsupportedClientAPI = StringError("unsupported ClientAPI")
+)

internal/platforms/glfw.go

@@ -14,7 +14,7 @@ import (
 // GLFWClientAPI identifies the render system that shall be initialized.
 type GLFWClientAPI string
 
-// GLFWClientAPI constants
+// This is a list of GLFWClientAPI constants.
 const (
 	GLFWClientAPIOpenGL2 GLFWClientAPI = "OpenGL2"
 	GLFWClientAPIOpenGL3 GLFWClientAPI = "OpenGL3"
@@ -36,7 +36,7 @@ func NewGLFW(io imgui.IO, clientAPI GLFWClientAPI) (*GLFW, error) {
 
 	err := glfw.Init()
 	if err != nil {
-		return nil, fmt.Errorf("failed to initialize glfw: %v", err)
+		return nil, fmt.Errorf("failed to initialize glfw: %w", err)
 	}
 
 	switch clientAPI {
@@ -50,13 +50,13 @@ func NewGLFW(io imgui.IO, clientAPI GLFWClientAPI) (*GLFW, error) {
 		glfw.WindowHint(glfw.OpenGLForwardCompatible, 1)
 	default:
 		glfw.Terminate()
-		return nil, fmt.Errorf("unsupported ClientAPI: <%s>", clientAPI)
+		return nil, ErrUnsupportedClientAPI
 	}
 
-	window, err := glfw.CreateWindow(1280, 720, "ImGui-Go GLFW+"+string(clientAPI)+" example", nil, nil)
+	window, err := glfw.CreateWindow(windowWidth, windowHeight, "ImGui-Go GLFW+"+string(clientAPI)+" example", nil, nil)
 	if err != nil {
 		glfw.Terminate()
-		return nil, fmt.Errorf("failed to create window: %v", err)
+		return nil, fmt.Errorf("failed to create window: %w", err)
 	}
 	window.MakeContextCurrent()
 	glfw.SwapInterval(1)
@@ -165,15 +165,15 @@ func (platform *GLFW) installCallbacks() {
 }
 
 var glfwButtonIndexByID = map[glfw.MouseButton]int{
-	glfw.MouseButton1: 0,
-	glfw.MouseButton2: 1,
-	glfw.MouseButton3: 2,
+	glfw.MouseButton1: mouseButtonPrimary,
+	glfw.MouseButton2: mouseButtonSecondary,
+	glfw.MouseButton3: mouseButtonTertiary,
 }
 
 var glfwButtonIDByIndex = map[int]glfw.MouseButton{
-	0: glfw.MouseButton1,
-	1: glfw.MouseButton2,
-	2: glfw.MouseButton3,
+	mouseButtonPrimary:   glfw.MouseButton1,
+	mouseButtonSecondary: glfw.MouseButton2,
+	mouseButtonTertiary:  glfw.MouseButton3,
 }
 
 func (platform *GLFW) mouseButtonChange(window *glfw.Window, rawButton glfw.MouseButton, action glfw.Action, mods glfw.ModifierKey) {

internal/platforms/sdl.go

@@ -13,7 +13,7 @@ import (
 // SDLClientAPI identifies the render system that shall be initialized.
 type SDLClientAPI string
 
-// SDLClientAPI constants
+// This is a list of SDLClientAPI constants.
 const (
 	SDLClientAPIOpenGL2 SDLClientAPI = "OpenGL2"
 	SDLClientAPIOpenGL3 SDLClientAPI = "OpenGL3"
@@ -27,7 +27,7 @@ type SDL struct {
 	shouldStop bool
 
 	time        uint64
-	buttonsDown [3]bool
+	buttonsDown [mouseButtonCount]bool
 }
 
 // NewSDL attempts to initialize an SDL context.
@@ -36,13 +36,14 @@ func NewSDL(io imgui.IO, clientAPI SDLClientAPI) (*SDL, error) {
 
 	err := sdl.Init(sdl.INIT_VIDEO)
 	if err != nil {
-		return nil, fmt.Errorf("failed to initialize SDL2: %v", err)
+		return nil, fmt.Errorf("failed to initialize SDL2: %w", err)
 	}
 
-	window, err := sdl.CreateWindow("ImGui-Go SDL2+"+string(clientAPI)+" example", sdl.WINDOWPOS_CENTERED, sdl.WINDOWPOS_CENTERED, 1280, 720, sdl.WINDOW_OPENGL)
+	window, err := sdl.CreateWindow("ImGui-Go SDL2+"+string(clientAPI)+" example",
+		sdl.WINDOWPOS_CENTERED, sdl.WINDOWPOS_CENTERED, windowWidth, windowHeight, sdl.WINDOW_OPENGL)
 	if err != nil {
 		sdl.Quit()
-		return nil, fmt.Errorf("failed to create window: %v", err)
+		return nil, fmt.Errorf("failed to create window: %w", err)
 	}
 
 	platform := &SDL{
@@ -62,7 +63,7 @@ func NewSDL(io imgui.IO, clientAPI SDLClientAPI) (*SDL, error) {
 		_ = sdl.GLSetAttribute(sdl.GL_CONTEXT_PROFILE_MASK, sdl.GL_CONTEXT_PROFILE_CORE)
 	default:
 		platform.Dispose()
-		return nil, fmt.Errorf("unsupported ClientAPI: <%s>", clientAPI)
+		return nil, ErrUnsupportedClientAPI
 	}
 	_ = sdl.GLSetAttribute(sdl.GL_DOUBLEBUFFER, 1)
 	_ = sdl.GLSetAttribute(sdl.GL_DEPTH_SIZE, 24)
@@ -71,12 +72,12 @@ func NewSDL(io imgui.IO, clientAPI SDLClientAPI) (*SDL, error) {
 	glContext, err := window.GLCreateContext()
 	if err != nil {
 		platform.Dispose()
-		return nil, fmt.Errorf("failed to create OpenGL context: %v", err)
+		return nil, fmt.Errorf("failed to create OpenGL context: %w", err)
 	}
 	err = window.GLMakeCurrent(glContext)
 	if err != nil {
 		platform.Dispose()
-		return nil, fmt.Errorf("failed to set current OpenGL context: %v", err)
+		return nil, fmt.Errorf("failed to set current OpenGL context: %w", err)
 	}
 
 	_ = sdl.GLSetSwapInterval(1)
@@ -129,7 +130,8 @@ func (platform *SDL) NewFrame() {
 	if platform.time > 0 {
 		platform.imguiIO.SetDeltaTime(float32(currentTime-platform.time) / float32(frequency))
 	} else {
-		platform.imguiIO.SetDeltaTime(1.0 / 60.0)
+		const fallbackDelta = 1.0 / 60.0
+		platform.imguiIO.SetDeltaTime(fallbackDelta)
 	}
 	platform.time = currentTime
 
@@ -200,11 +202,11 @@ func (platform *SDL) processEvent(event sdl.Event) {
 		buttonEvent := event.(*sdl.MouseButtonEvent)
 		switch buttonEvent.Button {
 		case sdl.BUTTON_LEFT:
-			platform.buttonsDown[0] = true
+			platform.buttonsDown[mouseButtonPrimary] = true
 		case sdl.BUTTON_RIGHT:
-			platform.buttonsDown[1] = true
+			platform.buttonsDown[mouseButtonSecondary] = true
 		case sdl.BUTTON_MIDDLE:
-			platform.buttonsDown[2] = true
+			platform.buttonsDown[mouseButtonTertiary] = true
 		}
 	case sdl.TEXTINPUT:
 		inputEvent := event.(*sdl.TextInputEvent)

internal/renderers/OpenGL2.go

@@ -20,7 +20,7 @@ type OpenGL2 struct {
 func NewOpenGL2(io imgui.IO) (*OpenGL2, error) {
 	err := gl.Init()
 	if err != nil {
-		return nil, fmt.Errorf("failed to initialize OpenGL: %v", err)
+		return nil, fmt.Errorf("failed to initialize OpenGL: %w", err)
 	}
 
 	renderer := &OpenGL2{
@@ -96,7 +96,8 @@ func (renderer *OpenGL2) Render(displaySize [2]float32, framebufferSize [2]float
 	indexSize := imgui.IndexBufferLayout()
 
 	drawType := gl.UNSIGNED_SHORT
-	if indexSize == 4 {
+	const bytesPerUint32 = 4
+	if indexSize == bytesPerUint32 {
 		drawType = gl.UNSIGNED_INT
 	}
 

internal/renderers/OpenGL3.go

@@ -31,7 +31,7 @@ type OpenGL3 struct {
 func NewOpenGL3(io imgui.IO) (*OpenGL3, error) {
 	err := gl.Init()
 	if err != nil {
-		return nil, fmt.Errorf("failed to initialize OpenGL: %v", err)
+		return nil, fmt.Errorf("failed to initialize OpenGL: %w", err)
 	}
 
 	renderer := &OpenGL3{
@@ -145,7 +145,8 @@ func (renderer *OpenGL3) Render(displaySize [2]float32, framebufferSize [2]float
 	gl.VertexAttribPointer(uint32(renderer.attribLocationColor), 4, gl.UNSIGNED_BYTE, true, int32(vertexSize), unsafe.Pointer(uintptr(vertexOffsetCol)))
 	indexSize := imgui.IndexBufferLayout()
 	drawType := gl.UNSIGNED_SHORT
-	if indexSize == 4 {
+	const bytesPerUint32 = 4
+	if indexSize == bytesPerUint32 {
 		drawType = gl.UNSIGNED_INT
 	}