third_party/WebKit/Source/devtools/front_end/cm/activeline.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 style the cursor's line.
   5 //
   6 // Adds an option 'styleActiveLine' which, when enabled, gives the
   7 // active line's wrapping <div> the CSS class "CodeMirror-activeline",
   8 // and gives its background <div> the class "CodeMirror-activeline-background".
   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   var WRAP_CLASS = "CodeMirror-activeline";
  20   var BACK_CLASS = "CodeMirror-activeline-background";
  21
  22   CodeMirror.defineOption("styleActiveLine", false, function(cm, val, old) {
  23     var prev = old && old != CodeMirror.Init;
  24     if (val && !prev) {
  25       cm.state.activeLines = [];
  26       updateActiveLines(cm, cm.listSelections());
  27       cm.on("beforeSelectionChange", selectionChange);
  28     } else if (!val && prev) {
  29       cm.off("beforeSelectionChange", selectionChange);
  30       clearActiveLines(cm);
  31       delete cm.state.activeLines;
  32     }
  33   });
  34
  35   function clearActiveLines(cm) {
  36     for (var i = 0; i < cm.state.activeLines.length; i++) {
  37       cm.removeLineClass(cm.state.activeLines[i], "wrap", WRAP_CLASS);
  38       cm.removeLineClass(cm.state.activeLines[i], "background", BACK_CLASS);
  39     }
  40   }
  41
  42   function sameArray(a, b) {
  43     if (a.length != b.length) return false;
  44     for (var i = 0; i < a.length; i++)
  45       if (a[i] != b[i]) return false;
  46     return true;
  47   }
  48
  49   function updateActiveLines(cm, ranges) {
  50     var active = [];
  51     for (var i = 0; i < ranges.length; i++) {
  52       var range = ranges[i];
  53       if (!range.empty()) continue;
  54       var line = cm.getLineHandleVisualStart(range.head.line);
  55       if (active[active.length - 1] != line) active.push(line);
  56     }
  57     if (sameArray(cm.state.activeLines, active)) return;
  58     cm.operation(function() {
  59       clearActiveLines(cm);
  60       for (var i = 0; i < active.length; i++) {
  61         cm.addLineClass(active[i], "wrap", WRAP_CLASS);
  62         cm.addLineClass(active[i], "background", BACK_CLASS);
  63       }
  64       cm.state.activeLines = active;
  65     });
  66   }
  67
  68   function selectionChange(cm, sel) {
  69     updateActiveLines(cm, sel.ranges);
  70   }
  71 });