third_party/WebKit/Source/devtools/front_end/cm/markselection.js

   1 // CodeMirror, copyright (c) by Marijn Haverbeke and others
   2 // Distributed under an MIT license: http://codemirror.net/LICENSE
   3
   4 // Because sometimes you need to mark the selected *text*.
   5 //
   6 // Adds an option 'styleSelectedText' which, when enabled, gives
   7 // selected text the CSS class given as option value, or
   8 // "CodeMirror-selectedtext" when the value is not a string.
   9
  10 (function(mod) {
  11   if (typeof exports == "object" && typeof module == "object") // CommonJS
  12     mod(require("../../lib/codemirror"));
  13   else if (typeof define == "function" && define.amd) // AMD
  14     define(["../../lib/codemirror"], mod);
  15   else // Plain browser env
  16     mod(CodeMirror);
  17 })(function(CodeMirror) {
  18   "use strict";
  19
  20   CodeMirror.defineOption("styleSelectedText", false, function(cm, val, old) {
  21     var prev = old && old != CodeMirror.Init;
  22     if (val && !prev) {
  23       cm.state.markedSelection = [];
  24       cm.state.markedSelectionStyle = typeof val == "string" ? val : "CodeMirror-selectedtext";
  25       reset(cm);
  26       cm.on("cursorActivity", onCursorActivity);
  27       cm.on("change", onChange);
  28     } else if (!val && prev) {
  29       cm.off("cursorActivity", onCursorActivity);
  30       cm.off("change", onChange);
  31       clear(cm);
  32       cm.state.markedSelection = cm.state.markedSelectionStyle = null;
  33     }
  34   });
  35
  36   function onCursorActivity(cm) {
  37     cm.operation(function() { update(cm); });
  38   }
  39
  40   function onChange(cm) {
  41     if (cm.state.markedSelection.length)
  42       cm.operation(function() { clear(cm); });
  43   }
  44
  45   var CHUNK_SIZE = 8;
  46   var Pos = CodeMirror.Pos;
  47   var cmp = CodeMirror.cmpPos;
  48
  49   function coverRange(cm, from, to, addAt) {
  50     if (cmp(from, to) == 0) return;
  51     var array = cm.state.markedSelection;
  52     var cls = cm.state.markedSelectionStyle;
  53     for (var line = from.line;;) {
  54       var start = line == from.line ? from : Pos(line, 0);
  55       var endLine = line + CHUNK_SIZE, atEnd = endLine >= to.line;
  56       var end = atEnd ? to : Pos(endLine, 0);
  57       var mark = cm.markText(start, end, {className: cls});
  58       if (addAt == null) array.push(mark);
  59       else array.splice(addAt++, 0, mark);
  60       if (atEnd) break;
  61       line = endLine;
  62     }
  63   }
  64
  65   function clear(cm) {
  66     var array = cm.state.markedSelection;
  67     for (var i = 0; i < array.length; ++i) array[i].clear();
  68     array.length = 0;
  69   }
  70
  71   function reset(cm) {
  72     clear(cm);
  73     var ranges = cm.listSelections();
  74     for (var i = 0; i < ranges.length; i++)
  75       coverRange(cm, ranges[i].from(), ranges[i].to());
  76   }
  77
  78   function update(cm) {
  79     if (!cm.somethingSelected()) return clear(cm);
  80     if (cm.listSelections().length > 1) return reset(cm);
  81
  82     var from = cm.getCursor("start"), to = cm.getCursor("end");
  83
  84     var array = cm.state.markedSelection;
  85     if (!array.length) return coverRange(cm, from, to);
  86
  87     var coverStart = array[0].find(), coverEnd = array[array.length - 1].find();
  88     if (!coverStart || !coverEnd || to.line - from.line < CHUNK_SIZE ||
  89         cmp(from, coverEnd.to) >= 0 || cmp(to, coverStart.from) <= 0)
  90       return reset(cm);
  91
  92     while (cmp(from, coverStart.from) > 0) {
  93       array.shift().clear();
  94       coverStart = array[0].find();
  95     }
  96     if (cmp(from, coverStart.from) < 0) {
  97       if (coverStart.to.line - from.line < CHUNK_SIZE) {
  98         array.shift().clear();
  99         coverRange(cm, from, coverStart.to, 0);
 100       } else {
 101         coverRange(cm, from, coverStart.from, 0);
 102       }
 103     }
 104
 105     while (cmp(to, coverEnd.to) < 0) {
 106       array.pop().clear();
 107       coverEnd = array[array.length - 1].find();
 108     }
 109     if (cmp(to, coverEnd.to) > 0) {
 110       if (to.line - coverEnd.from.line < CHUNK_SIZE) {
 111         array.pop().clear();
 112         coverRange(cm, coverEnd.from, to);
 113       } else {
 114         coverRange(cm, coverEnd.to, to);
 115       }
 116     }
 117   }
 118 });