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

   1 // CodeMirror, copyright (c) by Marijn Haverbeke and others
   2 // Distributed under an MIT license: http://codemirror.net/LICENSE
   3
   4 (function(mod) {
   5   if (typeof exports == "object" && typeof module == "object") // CommonJS
   6     mod(require("../../lib/codemirror"));
   7   else if (typeof define == "function" && define.amd) // AMD
   8     define(["../../lib/codemirror"], mod);
   9   else // Plain browser env
  10     mod(CodeMirror);
  11 })(function(CodeMirror) {
  12   var ie_lt8 = /MSIE \d/.test(navigator.userAgent) &&
  13     (document.documentMode == null || document.documentMode < 8);
  14
  15   var Pos = CodeMirror.Pos;
  16
  17   var matching = {"(": ")>", ")": "(<", "[": "]>", "]": "[<", "{": "}>", "}": "{<"};
  18
  19   function findMatchingBracket(cm, where, strict, config) {
  20     var line = cm.getLineHandle(where.line), pos = where.ch - 1;
  21     var match = (pos >= 0 && matching[line.text.charAt(pos)]) || matching[line.text.charAt(++pos)];
  22     if (!match) return null;
  23     var dir = match.charAt(1) == ">" ? 1 : -1;
  24     if (strict && (dir > 0) != (pos == where.ch)) return null;
  25     var style = cm.getTokenTypeAt(Pos(where.line, pos + 1));
  26
  27     var found = scanForBracket(cm, Pos(where.line, pos + (dir > 0 ? 1 : 0)), dir, style || null, config);
  28     if (found == null) return null;
  29     return {from: Pos(where.line, pos), to: found && found.pos,
  30             match: found && found.ch == match.charAt(0), forward: dir > 0};
  31   }
  32
  33   // bracketRegex is used to specify which type of bracket to scan
  34   // should be a regexp, e.g. /[[\]]/
  35   //
  36   // Note: If "where" is on an open bracket, then this bracket is ignored.
  37   //
  38   // Returns false when no bracket was found, null when it reached
  39   // maxScanLines and gave up
  40   function scanForBracket(cm, where, dir, style, config) {
  41     var maxScanLen = (config && config.maxScanLineLength) || 10000;
  42     var maxScanLines = (config && config.maxScanLines) || 1000;
  43
  44     var stack = [];
  45     var re = config && config.bracketRegex ? config.bracketRegex : /[(){}[\]]/;
  46     var lineEnd = dir > 0 ? Math.min(where.line + maxScanLines, cm.lastLine() + 1)
  47                           : Math.max(cm.firstLine() - 1, where.line - maxScanLines);
  48     for (var lineNo = where.line; lineNo != lineEnd; lineNo += dir) {
  49       var line = cm.getLine(lineNo);
  50       if (!line) continue;
  51       var pos = dir > 0 ? 0 : line.length - 1, end = dir > 0 ? line.length : -1;
  52       if (line.length > maxScanLen) continue;
  53       if (lineNo == where.line) pos = where.ch - (dir < 0 ? 1 : 0);
  54       for (; pos != end; pos += dir) {
  55         var ch = line.charAt(pos);
  56         if (re.test(ch) && (style === undefined || cm.getTokenTypeAt(Pos(lineNo, pos + 1)) == style)) {
  57           var match = matching[ch];
  58           if ((match.charAt(1) == ">") == (dir > 0)) stack.push(ch);
  59           else if (!stack.length) return {pos: Pos(lineNo, pos), ch: ch};
  60           else stack.pop();
  61         }
  62       }
  63     }
  64     return lineNo - dir == (dir > 0 ? cm.lastLine() : cm.firstLine()) ? false : null;
  65   }
  66
  67   function matchBrackets(cm, autoclear, config) {
  68     // Disable brace matching in long lines, since it'll cause hugely slow updates
  69     var maxHighlightLen = cm.state.matchBrackets.maxHighlightLineLength || 1000;
  70     var marks = [], ranges = cm.listSelections();
  71     for (var i = 0; i < ranges.length; i++) {
  72       var match = ranges[i].empty() && findMatchingBracket(cm, ranges[i].head, false, config);
  73       if (match && cm.getLine(match.from.line).length <= maxHighlightLen) {
  74         var style = match.match ? "CodeMirror-matchingbracket" : "CodeMirror-nonmatchingbracket";
  75         marks.push(cm.markText(match.from, Pos(match.from.line, match.from.ch + 1), {className: style}));
  76         if (match.to && cm.getLine(match.to.line).length <= maxHighlightLen)
  77           marks.push(cm.markText(match.to, Pos(match.to.line, match.to.ch + 1), {className: style}));
  78       }
  79     }
  80
  81     if (marks.length) {
  82       // Kludge to work around the IE bug from issue #1193, where text
  83       // input stops going to the textare whever this fires.
  84       if (ie_lt8 && cm.state.focused) cm.display.input.focus();
  85
  86       var clear = function() {
  87         cm.operation(function() {
  88           for (var i = 0; i < marks.length; i++) marks[i].clear();
  89         });
  90       };
  91       if (autoclear) setTimeout(clear, 800);
  92       else return clear;
  93     }
  94   }
  95
  96   var currentlyHighlighted = null;
  97   function doMatchBrackets(cm) {
  98     cm.operation(function() {
  99       if (currentlyHighlighted) {currentlyHighlighted(); currentlyHighlighted = null;}
 100       currentlyHighlighted = matchBrackets(cm, false, cm.state.matchBrackets);
 101     });
 102   }
 103
 104   CodeMirror.defineOption("matchBrackets", false, function(cm, val, old) {
 105     if (old && old != CodeMirror.Init)
 106       cm.off("cursorActivity", doMatchBrackets);
 107     if (val) {
 108       cm.state.matchBrackets = typeof val == "object" ? val : {};
 109       cm.on("cursorActivity", doMatchBrackets);
 110     }
 111   });
 112
 113   CodeMirror.defineExtension("matchBrackets", function() {matchBrackets(this, true);});
 114   CodeMirror.defineExtension("findMatchingBracket", function(pos, strict, config){
 115     return findMatchingBracket(this, pos, strict, config);
 116   });
 117   CodeMirror.defineExtension("scanForBracket", function(pos, dir, style, config){
 118     return scanForBracket(this, pos, dir, style, config);
 119   });
 120 });