notcurses/tests/internal.cpp

#include <string>
#include <cstdlib>
#include <clocale>
#include "main.h"

TEST_CASE("Internals") {

  SUBCASE("RGBtoANSIWhite") {
    unsigned r, g, b;
    for(r = 250 ; r < 256 ; ++r){
      g = b = r;
      CHECK(15 == rgb_quantize_256(r, g, b));
    }
  }

  SUBCASE("RGBtoANSIBlack") {
    unsigned r, g, b;
    for(r = 0 ; r < 10 ; ++r){
      g = b = r;
      CHECK(0 == rgb_quantize_256(r, g, b));
    }
  }

  SUBCASE("RGBtoANSIGrey") {
    unsigned r, g, b;
    for(r = 10 ; r < 244 ; ++r){
      g = b = r;
      CHECK(231 + (r * 5) / 49 == rgb_quantize_256(r, g, b));
    }
  }

  // Pure reds are either 0 (black), or 16 plus 36 * [0..5].
  SUBCASE("RGBtoANSIRed") {
    unsigned r, g, b;
    g = b = 0x0;
    for(r = 0 ; r < 256 ; ++r){
      int c256 = rgb_quantize_256(r, g, b);
      if(r < 8){
        CHECK(0 == c256);
      }else{
        CHECK(15 < c256);
        CHECK(16 == c256 % 36);
      }
    }
  }

  // Pure greens are either 0 (black), or 16 plus 6 * [0..5].
  SUBCASE("RGBtoANSIGreen") {
    unsigned r, g, b;
    r = b = 0x0;
    for(g = 0 ; g < 256 ; ++g){
      int c256 = rgb_quantize_256(r, g, b);
      CHECK(48 > c256);
      if(g < 8){
        CHECK(0 == c256);
      }else{
        CHECK(15 < c256);
        CHECK(4 == c256 % 6);
      }
    }
  }

  // Pure blues are either 0 (black), or one of the first 6 colors [16..22].
  SUBCASE("RGBtoANSIBlue") {
    unsigned r, g, b;
    r = g = 0x0;
    for(b = 0 ; b < 256 ; ++b){
      int c256 = rgb_quantize_256(r, g, b);
      CHECK(22 > c256);
      if(b < 8){
        CHECK(0 == c256);
      }else{
        CHECK(15 < c256);
      }
    }
  }

}