Add some basic tests

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
     steps:
     - name: Install dependencies (linux)
       if: ${{ matrix.os == 'ubuntu-latest' }}
-      run: sudo apt-get update && sudo apt-get install libgl1-mesa-dev
+      run: sudo apt-get update && sudo apt-get install libgl-dev libxcursor-dev libxi-dev libxinerama-dev libxrandr-dev libxxf86vm-dev xvfb
 
     - name: Check out module
       uses: actions/checkout@v2
@@ -29,5 +29,13 @@ jobs:
         go-version: ${{matrix.go-version}}
         go-version-file: go.mod
 
+      # Test that the package at least builds on all platforms
+    - name: Test build
+      run: go build -v ./...
+
     - name: Run tests
-      run: go test -v -race ./...
+      if: ${{ matrix.os == 'ubuntu-latest' }}
+      run: |
+        # Update dependencies here to avoid pulling glfw into go.mod
+        go mod tidy
+        xvfb-run go test -v

gl4_test.go

@@ -0,0 +1,161 @@
+package gl_test
+
+import (
+	"errors"
+	"runtime"
+	"testing"
+
+	"github.com/go-gl/gl/v4.1-core/gl"
+	"github.com/go-gl/glfw/v3.3/glfw"
+)
+
+func testIntegers(t *testing.T) {
+	// See https://registry.khronos.org/OpenGL-Refpages/gl4/html/glGet.xhtml
+	var data int32
+	gl.GetIntegerv(gl.MAJOR_VERSION, &data)
+	if data != 4 {
+		// OpenGL 5.0 released with raytracing...?
+		t.Error("invalid GL_MAJOR_VERSION:", data)
+	}
+	gl.GetIntegerv(gl.MAX_TEXTURE_SIZE, &data)
+	if data < 1024 {
+		// Guaranteed by spec
+		t.Error("invalid GL_MAX_TEXTURE_SIZE:", data)
+	}
+
+	if err := gl.GetError(); err != gl.NO_ERROR {
+		t.Error("glGetIntegerv():", err)
+	}
+}
+func testStrings(t *testing.T) {
+	// See https://registry.khronos.org/OpenGL-Refpages/gl4/html/glGetString.xhtml
+	gl.GetString(gl.VENDOR)
+	gl.GetString(gl.RENDERER)
+	gl.GetString(gl.VERSION)
+	gl.GetString(gl.SHADING_LANGUAGE_VERSION)
+	if err := gl.GetError(); err != gl.NO_ERROR {
+		t.Error("glGetString():", err)
+	}
+
+	gl.GetString(gl.MAX_TEXTURE_SIZE)
+	if err := gl.GetError(); err != gl.INVALID_ENUM {
+		t.Error("glGetString() failed to return GL_INVALID_ENUM:", err)
+	}
+}
+func testTextures(t *testing.T) {
+	var texture uint32
+	gl.GenTextures(1, &texture)
+	if texture == 0 {
+		t.Error("glGenTextures() returned zero")
+	}
+
+	// Textures must be bound before glIsTexture will recognize them.
+	// See https://registry.khronos.org/OpenGL-Refpages/gl4/html/glIsTexture.xhtml
+	gl.BindTexture(gl.TEXTURE_2D, texture)
+	if !gl.IsTexture(texture) {
+		t.Error("glIsTexture() failed to recognize a texture returned by glGenTextures()")
+	}
+
+	gl.DeleteTextures(1, &texture)
+	if gl.IsTexture(texture) {
+		t.Error("glDeleteTextures() did not delete texture")
+	}
+
+	if err := gl.GetError(); err != gl.NO_ERROR {
+		t.Error("texture error:", err)
+	}
+
+	gl.GenTextures(-1, &texture)
+	if err := gl.GetError(); err != gl.INVALID_VALUE {
+		t.Error("glGenTextures() failed to return GL_INVALID_VALUE:", err)
+	}
+}
+func testShader(t *testing.T, src string) error {
+	csrc, free := gl.Strs(src + "\x00")
+	defer free()
+
+	shader := gl.CreateShader(gl.VERTEX_SHADER)
+	if shader == 0 {
+		t.Error("glCreateShader() returned zero")
+	}
+	defer gl.DeleteShader(shader)
+
+	gl.ShaderSource(shader, 1, csrc, nil)
+	gl.CompileShader(shader)
+	if !gl.IsShader(shader) {
+		t.Error("glIsShader() failed to recognize a shader returned by glCreateShader()")
+	}
+
+	if err := gl.GetError(); err != gl.NO_ERROR {
+		t.Error("shader error:", err)
+	}
+
+	var data int32
+	gl.GetShaderiv(shader, gl.COMPILE_STATUS, &data)
+	if data == gl.TRUE {
+		return nil
+	}
+
+	gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &data)
+	infoLog := make([]byte, data+1)
+	gl.GetShaderInfoLog(shader, data, nil, &infoLog[0])
+	return errors.New(src + "\n" + string(infoLog))
+}
+
+func TestBasic(t *testing.T) {
+	// Each test runs in its own goroutine, so we need to lock OS threads here
+	// rather than in the init() function.
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	if err := glfw.Init(); err != nil {
+		t.Fatal("failed to initialize glfw:", err)
+	}
+	defer glfw.Terminate()
+
+	glfw.WindowHint(glfw.Visible, glfw.False)
+	glfw.WindowHint(glfw.ContextVersionMajor, 4)
+	glfw.WindowHint(glfw.ContextVersionMinor, 1)
+
+	// Needed for OS X
+	// https://www.glfw.org/faq.html#41---how-do-i-create-an-opengl-30-context
+	glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
+	glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
+
+	window, err := glfw.CreateWindow(800, 600, "Test", nil, nil)
+	if err != nil {
+		t.Fatal("failed to create glfw window:", err)
+	}
+	defer window.Destroy()
+	window.MakeContextCurrent()
+
+	if err := gl.Init(); err != nil {
+		t.Fatal("failed to initialize opengl:", err)
+	}
+
+	testIntegers(t)
+	testStrings(t)
+	testTextures(t)
+
+	err = testShader(t, `
+		#version 410
+		void main() {
+			gl_Position = vec4(0, 0, 0, 1);
+		}
+	`)
+	if err != nil {
+		t.Error("unexpected compile error:", err)
+	}
+
+	err = testShader(t, `
+		#version 410
+		void main() {
+			gl_Unlucky = vec13(13);
+		}
+	`)
+	if err == nil {
+		t.Error("unexpected successful compilation of invalid shader")
+	} else {
+		t.Log(err)
+	}
+}