Make contracted braille input work in more contexts.

chrome/browser/resources/chromeos/chromevox/braille/expanding_braille_translator.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview Translates text to braille, optionally with some parts
  * uncontracted.
  */
 
 goog.provide('cvox.ExpandingBrailleTranslator');
 
+goog.require('cvox.ExtraCellsSpan');
 goog.require('cvox.LibLouis');
 goog.require('cvox.Spannable');
 goog.require('cvox.ValueSelectionSpan');
 goog.require('cvox.ValueSpan');
 
 
 /**
  * A wrapper around one or two braille translators that uses contracted
  * braille or not based on the selection start- and end-points (if any) in the
  * translated text.  If only one translator is provided, then that translator
@@ skipping 59 matching lines @@
  * @param {!cvox.Spannable} text Text to translate.
  * @param {cvox.ExpandingBrailleTranslator.ExpansionType} expansionType
  *     Indicates how the text marked by a value span, if any, is expanded.
  * @param {function(!ArrayBuffer, !Array<number>, !Array<number>)}
  *     callback Called when the translation is done.  It takes resulting
  *         braille cells and positional mappings as parameters.
  */
 cvox.ExpandingBrailleTranslator.prototype.translate =
     function(text, expansionType, callback) {
   var expandRanges = this.findExpandRanges_(text, expansionType);
-  if (expandRanges.length == 0) {
+  var extraCellsSpans = text.getSpansInstanceOf(cvox.ExtraCellsSpan)
+      .filter(function(span) { return span.cells.byteLength > 0;});
+  var extraCellsPositions = extraCellsSpans.map(function(span) {
+    return text.getSpanStart(span);
+  });
+  if (expandRanges.length == 0 && extraCellsSpans.length == 0) {
     this.defaultTranslator_.translate(
         text.toString(),
         cvox.ExpandingBrailleTranslator.nullParamsToEmptyAdapter_(
             text.getLength(), callback));
     return;
   }
 
   var chunks = [];
+  function maybeAddChunkToTranslate(translator, start, end) {
+    if (start < end)
+      chunks.push({translator: translator, start: start, end: end});
+  }
+  function addExtraCellsChunk(pos, cells) {
+    var chunk = {translator: null,
+                 start: pos,
+                 end: pos,
+                 cells: cells,
+                 textToBraille: [],
+                 brailleToText: new Array(cells.byteLength)};
+    for (var i = 0; i < cells.byteLength; ++i)
+      chunk.brailleToText[i] = 0;
+    chunks.push(chunk);
+  }
   function addChunk(translator, start, end) {
-    chunks.push({translator: translator, start: start, end: end});
+    while (extraCellsSpans.length > 0 && extraCellsPositions[0] <= end) {
+      maybeAddChunkToTranslate(translator, start, extraCellsPositions[0]);
+      start = extraCellsPositions.shift();
+      addExtraCellsChunk(start, extraCellsSpans.shift().cells);
+    }
+    maybeAddChunkToTranslate(translator, start, end);
   }
   var lastEnd = 0;
   for (var i = 0; i < expandRanges.length; ++i) {
     var range = expandRanges[i];
     if (lastEnd < range.start) {
       addChunk(this.defaultTranslator_, lastEnd, range.start);
     }
     addChunk(this.uncontractedTranslator_, range.start, range.end);
     lastEnd = range.end;
   }
-  if (lastEnd < text.getLength()) {
-    addChunk(this.defaultTranslator_, lastEnd, text.getLength());
-  }
+  addChunk(this.defaultTranslator_, lastEnd, text.getLength());
 
-  var numPendingCallbacks = chunks.length;
+  var chunksToTranslate = chunks.filter(function(chunk) {
+    return chunk.translator;
+  });
+  var numPendingCallbacks = chunksToTranslate.length;
 
   function chunkTranslated(chunk, cells, textToBraille, brailleToText) {
     chunk.cells = cells;
     chunk.textToBraille = textToBraille;
     chunk.brailleToText = brailleToText;
-    if (--numPendingCallbacks <= 0) {
+    if (--numPendingCallbacks <= 0)
       finish();
-    }
   }
 
   function finish() {
     var totalCells = chunks.reduce(
         function(accum, chunk) { return accum + chunk.cells.byteLength}, 0);
     var cells = new Uint8Array(totalCells);
     var cellPos = 0;
     var textToBraille = [];
     var brailleToText = [];
     function appendAdjusted(array, toAppend, adjustment) {
       array.push.apply(array, toAppend.map(
           function(elem) { return adjustment + elem; }
           ));
     }
     for (var i = 0, chunk; chunk = chunks[i]; ++i) {
       cells.set(new Uint8Array(chunk.cells), cellPos);
       appendAdjusted(textToBraille, chunk.textToBraille, cellPos);
       appendAdjusted(brailleToText, chunk.brailleToText, chunk.start);
       cellPos += chunk.cells.byteLength;
     }
     callback(cells.buffer, textToBraille, brailleToText);
   }
 
-  for (var i = 0, chunk; chunk = chunks[i]; ++i) {
-    chunk.translator.translate(
-        text.toString().substring(chunk.start, chunk.end),
-        cvox.ExpandingBrailleTranslator.nullParamsToEmptyAdapter_(
-            chunk.end - chunk.start, goog.partial(chunkTranslated, chunk)));
+  if (chunksToTranslate.length > 0) {
+    chunksToTranslate.forEach(function(chunk) {
+      chunk.translator.translate(
+          text.toString().substring(chunk.start, chunk.end),
+          cvox.ExpandingBrailleTranslator.nullParamsToEmptyAdapter_(
+              chunk.end - chunk.start, goog.partial(chunkTranslated, chunk)));
+    });
+  } else {
+    finish();
   }
 };
 
 
 /**
  * Expands a position to a range that covers the consecutive range of
  * either whitespace or non whitespace characters around it.
  * @param {string} str Text to look in.
  * @param {number} pos Position to start looking at.
  * @param {number} start Minimum value for the start position of the returned
@@ skipping 140 matching lines @@
   };
 };
 
 
 /**
  * A character range with inclusive start and exclusive end positions.
  * @typedef {{start: number, end: number}}
  * @private
  */
 cvox.ExpandingBrailleTranslator.Range_;