OpenGL ES 2.0 triangle on macOS using ANGLE

MyOpenGLView.m

#import "MyOpenGLView.h"
#import <GLES2/gl2.h>
#import <GLES2/gl2ext.h>
#import <EGL/egl.h>

const GLchar vertexShaderSource[] =
    "attribute vec3 aPosition;\n"
    "void main() {\n"
    "    gl_Position = vec4(aPosition, 1.0);\n"
    "}\n";

const GLchar fragmentShaderSource[] =
    "precision mediump float;\n"
    "void main() {\n"
    "   gl_FragColor = vec4(1.0, 1.0, 0.0, 1.0);\n"
    "}\n";

GLuint getShader(GLenum type, const GLchar* shaderSource)
{
    GLuint shader;
    GLint compiled;
    
    shader = glCreateShader(type);
    
    if (shader == 0) {
        NSLog(@"cannot create shader");
        return 0;
    }
    
    glShaderSource(shader, 1, &shaderSource, NULL);
    glCompileShader(shader);
    glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled);
    if (!compiled) {
        NSLog(@"cannot compile shader");
        return 0;
    }
    return shader;
}


GLuint createProgram()
{
    GLuint program = glCreateProgram();
    GLuint vertexShader = getShader(GL_VERTEX_SHADER, vertexShaderSource);
    GLuint fragmentShader = getShader(GL_FRAGMENT_SHADER, fragmentShaderSource);
    glAttachShader(program, vertexShader);
    glAttachShader(program, fragmentShader);
    glLinkProgram(program);
    return program;
}

@implementation MyOpenGLView

- (void) drawRect: (NSRect) bounds
{
    NSLog(@"draw rect");
    
    // **********************
    // *** Initialize ***
    // **********************
    EGLint majorVersion;
    EGLint minorVersion;
    EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
    if (display == EGL_NO_DISPLAY) {
        NSLog(@"no display");
        return;
    }
    if (!eglInitialize(display, &majorVersion, &minorVersion)) {
        NSLog(@"can't initialize");
        return;
    }
    
    EGLNativeWindowType* nativeWindow = (__bridge EGLNativeWindowType)(self.layer);
    
    
    
    
    // **********************
    // *** Choose config ***
    // **********************
    EGLint configAttribList[] = {
        EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
        EGL_RED_SIZE, 5,
        EGL_GREEN_SIZE, 6,
        EGL_BLUE_SIZE, 5,
        EGL_DEPTH_SIZE, 1,
        EGL_NONE
    };
    EGLConfig configs[10];
    EGLint numConfigs;
    if (!eglChooseConfig(display, configAttribList, configs, 10, &numConfigs)) {
        NSLog(@"no config");
        return;
    } else {
        NSLog(@"yes config! %d", numConfigs);
    }
    EGLConfig config = configs[0];
    
    
    
    
    // **********************
    // *** Create surface ***
    // **********************
    EGLSurface window = eglCreateWindowSurface(display, config, nativeWindow, NULL);
    
    if (window == EGL_NO_SURFACE) {
        NSLog(@"no window");
        return;
    } else {
        NSLog(@"yes surface!");
    }
    
    
    
    // **********************
    // *** Create context ***
    // **********************
    const EGLint contextAttribList[] = {
        EGL_CONTEXT_CLIENT_VERSION, 2,
        EGL_NONE
    };
    EGLContext context = eglCreateContext(display, config, EGL_NO_CONTEXT, contextAttribList);
    if (context == EGL_NO_CONTEXT) {
        NSLog(@"no context");
        return;
    } else {
        NSLog(@"yes context!");
    }
    
    // **********************
    // *** Make current ***
    // **********************
    if (!eglMakeCurrent(display, window, window, context)) {
        NSLog(@"can't make current");
        return;
    }
    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    
    
    
    // **********************
    // *** Draw triangle ***
    // **********************
    GLuint program = createProgram();
    
    GLfloat vVertices[] = {0.0f,  0.5f, 0.0f,
    -0.5f, -0.5f, 0.0f,
    0.5f, -0.5f,  0.0f};
    glViewport(0, 0, self.bounds.size.width, self.bounds.size.height);
    glClear(GL_COLOR_BUFFER_BIT);
    glUseProgram(program);
    glVertexAttribPointer(0, 3, GL_FLOAT, false, 0, vVertices);
    glUniform3f(glGetUniformLocation(program, "uColor"), 1.0, 0.0, 0.0);
    glEnableVertexAttribArray(0);
    glDrawArrays(GL_TRIANGLES, 0, 3);
    
    eglSwapBuffers(display, window);
    NSLog(@"draw rect end");
}
@end