tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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test_text_lengthAdjust.html (3455B)


      1 <!DOCTYPE html>
      2 <html>
      3 <!--
      4 https://bugzilla.mozilla.org/show_bug.cgi?id=569722
      5 -->
      6 <head>
      7  <meta charset=UTF-8>
      8  <title>Test for Bug 569722</title>
      9  <script src="/tests/SimpleTest/SimpleTest.js"></script>
     10  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
     11 </head>
     12 <body>
     13 <a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=569722">Mozilla Bug 569722</a>
     14 <p id="display"></p>
     15 <div id="content">
     16  <svg width="400" height="200">
     17    <text x="0" y="100" style="font: 16px sans-serif">aaa</text>
     18  </svg>
     19 </div>
     20 
     21 <pre id="test">
     22 <script class="testbody" type="application/javascript">
     23 SimpleTest.waitForExplicitFinish();
     24 
     25 function close(x, y, message) {
     26  ok(Math.abs(x - y) < 1e-4, message);
     27 }
     28 
     29 function runTest() {
     30  var text = document.querySelector("text");
     31 
     32  // get the original length
     33  var length = text.getComputedTextLength();
     34 
     35  // get the original glyph positions
     36  var startPositions = [],
     37      endPositions = [],
     38      extents = [];
     39  for (let i = 0; i < 3; i++) {
     40    startPositions.push(text.getStartPositionOfChar(i));
     41    endPositions.push(text.getEndPositionOfChar(i));
     42    extents.push(text.getExtentOfChar(i));
     43  }
     44 
     45  // widths should all be the same
     46  is(extents[0].width, extents[1].width);
     47  is(extents[0].width, extents[2].width);
     48 
     49  var checkCharNumAtPosition = function(x, y, i) {
     50    var p = document.querySelector("svg").createSVGPoint();
     51    p.x = x;
     52    p.y = y;
     53    is(text.getCharNumAtPosition(p), i, "getCharNumAtPosition(" + i + ")");
     54  };
     55 
     56  var checkPositions = function(start, end, width) {
     57    for (let i = 0; i < 3; i++) {
     58      // check their positions
     59      close(text.getStartPositionOfChar(i).x, start[i], "start position of glyph " + i);
     60      close(text.getEndPositionOfChar(i).x, end[i], "end position of glyph " + i);
     61      close(text.getExtentOfChar(i).x, start[i], "left edge of extent of glyph " + i);
     62      close(text.getExtentOfChar(i).width, width, "width of glyph " + i);
     63      checkCharNumAtPosition((start[i] + end[i]) / 2, 100, i);
     64    }
     65  };
     66 
     67  var w = extents[0].width;
     68 
     69  var doLengthAdjustSpacingTest = function() {
     70    // getComputedTextLength should return the sum of the advances, and since
     71    // we are just changing the positions of the glyphs, it should be the same
     72    // as without a textLength="" attribute
     73    close(text.getComputedTextLength(), length, "getComputedTextLength when lengthAdjust=\"spacing\"");
     74 
     75    // expected start and end positions of the glyphs
     76    var start = [0, 50 - w / 2, 100 - w];
     77    var end = [w, 50 + w / 2, 100];
     78    checkPositions(start, end, w);
     79  };
     80 
     81  // switch to adjust glyph positions, using the default value of lengthAdjust=""
     82  text.setAttribute("textLength", "100");
     83  doLengthAdjustSpacingTest();
     84  // then with an explicit lengthAdjust="spacing"
     85  text.setAttribute("lengthAdjust", "spacing");
     86  doLengthAdjustSpacingTest();
     87 
     88  // now test with lengthAdjust="spacingAndGlyphs"
     89  text.setAttribute("lengthAdjust", "spacingAndGlyphs");
     90 
     91  // now that each glyph is stretched, the total advance should be the textLength
     92  close(text.getComputedTextLength(), 100, "getComputedTextLength when lengthAdjust=\"spacingAndGlyphs\"");
     93 
     94  // expected start and end positions of the glyphs
     95  var start = [0, 33.3333, 66.6666];
     96  var end = [33.3333, 66.6666, 100];
     97  checkPositions(start, end, 33.3333);
     98 
     99  SimpleTest.finish();
    100 }
    101 
    102 window.addEventListener("load", runTest);
    103 </script>
    104 </pre>
    105 </body>
    106 </html>