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    NodeJS module to compare two DOM-trees

    Works with Node.JS v0.10+

    DOM Comparison

    Consider two documents. Expected:

        <!-- comment -->
        <element attribute="10" attributeX="100">
            <text>  text content </text>
                <node />
        <![CDATA[  cdata node]]>

    and actual one:

        <element attribute="100">
            <text>text content</text>
            <inner />
            <inner2 />
        <![CDATA[cdata node  ]]>

    One can compare them, get the result (is them equals, or not), and get extended report (why them are different).

    var compare = require('dom-compare').compare,
        reporter = require('dom-compare').GroupingReporter,
        expected = ..., // expected DOM tree
        actual = ..., // actual one
        result, diff, groupedDiff;
    // compare to DOM trees, get a result object
    result = compare(expected, actual);
    // get comparison result
    console.log(result.getResult()); // false cause' trees are different
    // get all differences
    diff = result.getDifferences(); // array of diff-objects
    // differences, grouped by node XPath
    groupedDiff = reporter.getDifferences(result); // object, key - node XPATH, value - array of differences (strings)
    // string representation

    Diff-object has a following form:

        node: "/document/element",
        message: "Attribute 'attribute': expected value '10' instead of '100'";

    By using GroupingReporter one can get a result of a following type

        '/document/element': [
            "Attribute 'attribute': expected value '10' instead of '100'",
            "Extra attribute 'attributeX'"

    Comparison options

    Comparison function can take a third argument with options like this:

    var options = {
        stripSpaces: true,
        compareComments: true
    result = compare(expected, actual, options);

    Comments comparison

    By default, all comments are ignored. Set compareComments options to true to compare them too.

    Whitespace comparison

    By default, all text nodes (text, CDATA, comments if enabled as mentioned above) compared with respect to leading and trailing whitespaces. Set stripSpaces option to true to automatically strip spaces in text and comment nodes. This option doesn't change the way CDATA sections is compared, they are always compared with respect to whitespaces.

    Cli utility

    When installed globally with npm install -g dom-compare cli utility is available. See usage information and command-line options with domcompare --help

    You can try it on bundled samples:

      $ cd samples
      $ domcompare -s ./expected.xml ./actual.xml
      Documents are not equal
          Attribute 'attribute': expected value '10' instead of '100'
          Attribute 'attributeX' is missed
          Extra element 'inner2'
          Element 'node' is missed
          Expected CDATA value '  cdata node' instead of 'cdata node  '

    DOM Canonic Form

    Implemented as XMLSerializer interface

    Simple rules

    1. Every node (text, node, attribute) on a new line
    2. Empty tags - in a short form
    3. Node indent - 4 spaces, attribute indent - 2 spaces
    4. Attributes are sorted alphabetically
    5. Attribute values are serialized in double quotes

    Consider the following XML-document...

      <element>DOM Compare</element>
      <element attribute1="value" attribute2="value">
        <element>Text node</element>

    ...and code snippet...

    var canonizingSerializer = new (require('dom-compare').XMLSerializer)();
    var doc = ...; // parse above document somehow 

    You'll receive the following output

            DOM Compare
        <emptyNode />
                Text node


    npm i dom-compare

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