jsdiff
A javascript text differencing implementation.
Based on the algorithm proposed in "An O(ND) Difference Algorithm and its Variations" (Myers, 1986).
Installation
npm install diff
or
git clone git://github.com/kpdecker/jsdiff.git
API
-
JsDiff.diffChars(oldStr, newStr)
- diffs two blocks of text, comparing character by character.Returns a list of change objects (See below).
-
JsDiff.diffWords(oldStr, newStr)
- diffs two blocks of text, comparing word by word.Returns a list of change objects (See below).
-
JsDiff.diffLines(oldStr, newStr)
- diffs two blocks of text, comparing line by line.Returns a list of change objects (See below).
-
JsDiff.diffCss(oldStr, newStr)
- diffs two blocks of text, comparing CSS tokens.Returns a list of change objects (See below).
-
JsDiff.createPatch(fileName, oldStr, newStr, oldHeader, newHeader)
- creates a unified diff patch.Parameters:
fileName
: String to be output in the filename sections of the patcholdStr
: Original string valuenewStr
: New string valueoldHeader
: Additional information to include in the old file headernewHeader
: Additional information to include in thew new file header
-
JsDiff.applyPatch(oldStr, diffStr)
- applies a unified diff patch.Return a string containing new version of provided data.
-
convertChangesToXML(changes)
- converts a list of changes to a serialized XML format
Change Objects
Many of the methods above return change objects. These objects are consist of the following fields:
value
: Text contentadded
: True if the value was inserted into the new stringremoved
: True of the value was removed from the old string
Note that some cases may omit a particular flag field. Comparison on the flag fields should always be done in a truthy or falsy manner.
Examples
Basic example in Node
require('colors')
var jsdiff = require('diff');
var one = 'beep boop';
var other = 'beep boob blah';
var diff = jsdiff.diffChars(one, other);
diff.forEach(function(part){
// green for additions, red for deletions
// grey for common parts
var color = part.added ? 'green' :
part.removed ? 'red' : 'grey';
process.stderr.write(part.value[color]);
});
console.log()
Running the above program should yield
Basic example in a web page
<pre id="display"></pre>
<script src="diff.js"></script>
<script>
var one = 'beep boop';
var other = 'beep boob blah';
var diff = JsDiff.diffChars(one, other);
diff.forEach(function(part){
// green for additions, red for deletions
// grey for common parts
var color = part.added ? 'green' :
part.removed ? 'red' : 'grey';
var span = document.createElement('span');
span.style.color = color;
span.appendChild(document
.createTextNode(part.value));
display.appendChild(span);
});
</script>
Open the above .html file in a browser and you should see
License
Software License Agreement (BSD License)
Copyright (c) 2009-2011, Kevin Decker kpdecker@gmail.com
All rights reserved.
Redistribution and use of this software in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
-
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
-
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
-
Neither the name of Kevin Decker nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.