1 files changed, 33 insertions, 5 deletions

diff --git a/scripts/theme-studio/test-colormath.mjs b/scripts/theme-studio/test-colormath.mjs
index 992d35bcc..a1ec9264e 100644
--- a/scripts/theme-studio/test-colormath.mjs
+++ b/scripts/theme-studio/test-colormath.mjs
@@ -13,14 +13,13 @@ import {
   srgb2oklab, oklab2oklch, oklch2oklab, oklch2hex, apca, deltaE,
   hex2rgb, rl, contrast, rating, hsv2rgb, rgb2hsv, rgb2hex,
   oklab2lrgb, inGamut, lrgb2hex, planeCell, paletteWarnings,
-  reliefColors,
+  reliefColors, isPureEndpointHex,
 } from './colormath.js';
 
 const close = (a, b, eps = 0.005) => Math.abs(a - b) <= eps;
 const here = fileURLToPath(new URL('.', import.meta.url));
-// Same export-strip generate.py applies before inlining (drop `export` lines, rstrip).
-const stripExports = (s) =>
-  s.split('\n').filter((l) => !l.startsWith('export')).join('\n').replace(/\s+$/, '');
+// Same strip generate.py applies before inlining (drop export/import lines, rstrip).
+import { stripInlinedBody } from './inline-strip.mjs';
 
 test('srgb2oklab achromatic anchors', () => {
   const w = srgb2oklab('#ffffff');
@@ -266,7 +265,36 @@ test('reliefColors: malformed hex returns null pair (Error)', () => {
 // body (sans exports) verbatim, so the inlined copy and the tested module cannot
 // drift. Requires `python3 generate.py` to have run first.
 test('inline-integrity: theme-studio.html contains the colormath.js body verbatim', () => {
-  const body = stripExports(readFileSync(here + 'colormath.js', 'utf8'));
+  const body = stripInlinedBody(readFileSync(here + 'colormath.js', 'utf8'));
   const html = readFileSync(here + 'theme-studio.html', 'utf8');
   assert.ok(html.includes(body), 'generated page is missing the colormath.js body verbatim');
 });
+
+// --- apca contrast branches + isPureEndpointHex ------------------------------
+
+test('apca: Boundary — equal luminance returns 0 (below the delta-Y floor)', () => {
+  assert.equal(apca('#808080', '#808080'), 0);
+});
+test('apca: Normal — dark text on light background is positive (Ybg > Ytxt)', () => {
+  assert.ok(apca('#000000', '#ffffff') > 0);
+});
+test('apca: Normal — light text on dark background is negative (else branch)', () => {
+  assert.ok(apca('#ffffff', '#000000') < 0);
+});
+test('apca: Boundary — near-equal colors below the floor clamp to 0', () => {
+  assert.equal(apca('#808080', '#828282'), 0);
+});
+
+test('isPureEndpointHex: Normal — pure black and white are endpoints', () => {
+  assert.equal(isPureEndpointHex('#ffffff'), true);
+  assert.equal(isPureEndpointHex('#000000'), true);
+  assert.equal(isPureEndpointHex('#FFFFFF'), true);
+});
+test('isPureEndpointHex: Boundary — any other color is not an endpoint', () => {
+  assert.equal(isPureEndpointHex('#010101'), false);
+  assert.equal(isPureEndpointHex('#123456'), false);
+});
+test('isPureEndpointHex: Error — null/empty is not an endpoint', () => {
+  assert.equal(isPureEndpointHex(null), false);
+  assert.equal(isPureEndpointHex(''), false);
+});