2d.text.measure.text-clusters-split.tentative.html (1929B)
1 <!DOCTYPE html> 2 <!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. --> 3 <meta charset="UTF-8"> 4 <title>OffscreenCanvas test: 2d.text.measure.text-clusters-split.tentative</title> 5 <script src="/resources/testharness.js"></script> 6 <script src="/resources/testharnessreport.js"></script> 7 <script src="/html/canvas/resources/canvas-tests.js"></script> 8 9 <h1>2d.text.measure.text-clusters-split.tentative</h1> 10 <p class="desc">Test that getTextClusters() splits the input correctly into the minimal clusters, keeping emojis together.</p> 11 12 13 <script> 14 var t = async_test("Test that getTextClusters() splits the input correctly into the minimal clusters, keeping emojis together."); 15 var t_pass = t.done.bind(t); 16 var t_fail = t.step_func(function(reason) { 17 throw reason; 18 }); 19 t.step(function() { 20 21 var canvas = new OffscreenCanvas(400, 200); 22 var ctx = canvas.getContext('2d'); 23 24 function getClusterIndexes(text) { 25 const clusters = ctx.measureText(text).getTextClusters(); 26 const result = []; 27 for (let i = 0; i < clusters.length; i++) { 28 const end = clusters[i].end; 29 if (end === (i + 1 < clusters.length ? clusters[i + 1].start : text.length)) { 30 result.push(clusters[i].start); 31 } else { 32 result.push([clusters[i].start, clusters[i].end]); 33 } 34 } 35 return result; 36 } 37 38 function assertClusterIndexes(text, expected) { 39 const actual = getClusterIndexes(text); 40 assert_array_equals(actual, expected); 41 } 42 43 ctx.font = '50px serif'; 44 const text = 'ABC ☺️❤️'; 45 ctx.fillText(text, 20, 100); 46 assertClusterIndexes(text, [0, 1, 2, 3, 4, 6]); 47 48 // [UAX#29]: https://unicode.org/reports/tr29/ 49 // [UAX#29] GB9: × (Extend | ZWJ) 50 assertClusterIndexes('X\u200DY', [0, 2]); 51 // [UAX#29] GB11: \p{Extended_Pictographic} Extend* ZWJ × \p{Extended_Pictographic} 52 assertClusterIndexes('\u{1FFFD}\u200D\u{1FFFD}', [0]); 53 t.done(); 54 55 }); 56 </script>