Copy/paste detector for programming source code, supports 150 formats.

Copy/paste is a common technical debt on a lot of projects. The jscpd gives the ability to find duplicated blocks implemented on more than 150 programming languages and digital formats of documents. The jscpd tool implements Rabin-Karp algorithm for searching duplications.

• Detect duplications in programming source code, use semantic of programing languages, can skip comments, empty lines etc.

• Detect duplications in embedded blocks of code, like <script> or <style> sections in html

• Blame authors of duplications

• Generate XML report in pmd-cpd format, JSON report, HTML report

• Integrate with CI systems, use thresholds for level of duplications

• The powerful API for extend functionality and usage

• Powerful development API written on TypeScript (no more CoffeeScript)
• Supports more formats (moved source code tokenizer from CodeMirror to Prism.js)
• New reporters: html, badge (badge reporter is separate package jscpd-badge-reporter)
• Add blamed lines to JSON report
• Default config file is .jscpd.json, no more .cpd.yaml
• Detect different formats in one file, like js scripts in html tags
• Allow to use multiple cli options for parameters like jscpd --ignore tests,build
• Allow multiple paths for detection like jscpd ./src ./tests ./docs
• Statistic of detection
• Use patterns form .gitignore for ignoring detection
• Ignored blocks in code

The old version of jscpd here

$ npx jscpd /path/to/source

or

$ npm install -g jscpd

$ jscpd /path/to/code

Minimal block size of code in lines. The block of code less than min-lines will be skipped.

• Cli options: --min-lines, -l
• Type: number
• Default: 5

Maximum file size in lines. The file bigger than max-lines will be skipped.

• Cli options: --max-lines, -x
• Type: number
• Default: 500

Maximum file size in bytes. The file bigger than max-size will be skipped.

• Cli options: --max-size, -z
• Type: string
• Default: 30kb

The threshold for duplication level, check if current level of duplications bigger than threshold jscpd exit with error.

• Cli options: --threshold, -t
• Type: number
• Default: null

The path to configuration file. The config should be in json format. Supported options in config file can be the same with cli options.

• Cli options: --config, -c
• Type: path
• Default: null

The option with glob patterns to ignore from analyze. For multiple globs you can use coma as separator. Example:

$ jscpd --ignore "**/*.min.js,**/*.map" /path/to/files

• Cli options: --ignore, -i
• Type: string
• Default: null

The list of reporters. Reporters use for output information of clones and duplication process.

Available reporters:

• console - report about clones to console;
• consoleFull - report about clones to console with blocks of code;
• json - output jscpd-report.json file with clones report in json format;
• xml - output jscpd-report.xml file with clones report in xml format;
• html - output jscpd-report.html file with clones report;
• verbose - output a lot of debug information to console;
• time - output all time of execution;

Note: A reporter can be developed manually, see API section.

• Cli options: --reporters, -r
• Type: string
• Default: console,time

The path to directory for reports. JSON and XML reports will be saved there.

• Cli options: --output, -o
• Type: path
• Default: ./report/

The mode of detection quality.

• strict - use all types of symbols as token, skip only blocks marked as ignored.
• mild - skip blocks marked as ignored and new lines and empty symbols.
• weak - skip blocks marked as ignored and new lines and empty symbols and comments.

Note: A mode can be developed manually, see API section.

• Cli options: --mode, -m
• Type: string
• Default: mild

The list of formats to detect for duplications. Available over 150 formats.

Example:

$ jscpd --format "php,javascript,markup,css" /path/to/files

• Cli options: --format, -f
• Type: string
• Default: {all formats}

Get information about authors and dates of duplicated blocks from git.

• Cli options: --blame, -b
• Type: boolean
• Default: false

Don't write a lot of information to a console.

Example:

$ jscpd /path/to/source --silent
Duplications detection: Found 60 exact clones with 3414(46.81%) duplicated lines in 100 (31 formats) files.
Execution Time: 1381.759ms

• Cli options: --silent, -s
• Type: boolean
• Default: false

Use the absolute path in reports.

• Cli options: --absolute, -a
• Type: boolean
• Default: false

Define the list of formats with file extensions. Available over 150 formats.

In following example jscpd will analyze files *.es and *.es6 as javascript and *.dt files as dart:

$ jscpd --formats-exts javascript:es,es6;dart:dt /path/to/code 

Note: formats defined in the option redefine default configuration, you should define all need formats manually or create two configuration for run jscpd

• Cli options: --formats-exts
• Type: string
• Default: null

Put .jscpd.json file in the root of the projects:

{
  "threshold": 0.1,
  "reporters": ["html", "console", "badge"],
  "ignore": ["**/__snapshots__/**"],
  "absolute": true
}

Also you can use section in package.json:

{
  ...
  "jscpd": {
    "threshold": 0.1,
    "reporters": ["html", "console", "badge"],
    "ignore": ["**/__snapshots__/**"],
    "absolute": true,
    "gitignore": true
  }
  ...
}

Mark blocks in code as ignored:

/* jscpd:ignore-start */
import lodash from 'lodash';
import React from 'react';
import {User} from './models';
import {UserService} from './services';
/* jscpd:ignore-end */

<!--jscpd:ignore-start-->
<meta data-react-helmet="true" name="theme-color" content="#cb3837"/>
<link data-react-helmet="true" rel="stylesheet" href="https://static.npmjs.com/103af5b8a2b3c971cba419755f3a67bc.css"/>
<link data-react-helmet="true" rel="stylesheet" href="https://static.npmjs.com/cms/flatpages.css"/>
<link data-react-helmet="true" rel="apple-touch-icon" sizes="120x120" href="https://static.npmjs.com/58a19602036db1daee0d7863c94673a4.png"/>
<link data-react-helmet="true" rel="apple-touch-icon" sizes="144x144" href="https://static.npmjs.com/7a7ffabbd910fc60161bc04f2cee4160.png"/>
<link data-react-helmet="true" rel="apple-touch-icon" sizes="152x152" href="https://static.npmjs.com/34110fd7686e2c90a487ca98e7336e99.png"/>
<link data-react-helmet="true" rel="apple-touch-icon" sizes="180x180" href="https://static.npmjs.com/3dc95981de4241b35cd55fe126ab6b2c.png"/>
<link data-react-helmet="true" rel="icon" type="image/png" href="https://static.npmjs.com/b0f1a8318363185cc2ea6a40ac23eeb2.png" sizes="32x32"/>
<!--jscpd:ignore-end-->

Demo report

More info jscpd-badge-reporter

<?xml version="1.0" encoding="utf-8"?>
<pmd-cpd>
  <duplication lines="10">
      <file path="/path/to/file" line="1">
        <codefragment><![CDATA[ ...first code fragment... ]]></codefragment>
      </file>
      <file path="/path/to/file" line="5">
        <codefragment><![CDATA[ ...second code fragment...}]]></codefragment>
      </file>
      <codefragment><![CDATA[ ...duplicated fragment... ]]></codefragment>
  </duplication>
</pmd-cpd>

{
  "duplications": [{
      "format": "javascript",
      "lines": 27,
      "fragment": "...code fragment... ",
      "tokens": 0,
      "firstFile": {
        "name": "tests/fixtures/javascript/file2.js",
        "start": 1,
        "end": 27,
        "startLoc": {
          "line": 1,
          "column": 1
        },
        "endLoc": {
          "line": 27,
          "column": 2
        }
      },
      "secondFile": {
        "name": "tests/fixtures/javascript/file1.js",
        "start": 1,
        "end": 24,
        "startLoc": {
          "line": 1,
          "column": 1
        },
        "endLoc": {
          "line": 24,
          "column": 2
        }
      }
  }],
  "statistic": {
    "detectionDate": "2018-11-09T15:32:02.397Z",
    "formats": {
      "javascript": {
        "sources": {
          "/path/to/file": {
            "lines": 24,
            "sources": 1,
            "clones": 1,
            "duplicatedLines": 26,
            "percentage": 45.33,
            "newDuplicatedLines": 0,
            "newClones": 0
          }
        },
        "total": {
          "lines": 297,
          "sources": 1,
          "clones": 1,
          "duplicatedLines": 26,
          "percentage": 45.33,
          "newDuplicatedLines": 0,
          "newClones": 0
        }
      }
    },
    "total": {
      "lines": 297,
      "sources": 6,
      "clones": 5,
      "duplicatedLines": 26,
      "percentage": 45.33,
      "newDuplicatedLines": 0,
      "newClones": 0
    },
    "threshold": 10
  }
}

import {
  JSCPD, 
  IClone,
  IOptions, 
  MATCH_SOURCE_EVENT, 
  CLONE_FOUND_EVENT,
  SOURCE_SKIPPED_EVENT,
  END_EVENT
} from 'jscpd';

const options: IOptions = {};

const cpd = new JSCPD(options);

const code = '...string with my code...';

cpd.on(MATCH_SOURCE_EVENT, (source) => {
  // new source detection started
  console.log(source);
});

cpd.on(CLONE_FOUND_EVENT, (clone: IClone) => {
  // clone found event
  console.log(clone);
});

cpd.on(SOURCE_SKIPPED_EVENT, (stat) => {
  // skipped source due size (see max-size, min-lines and max-lines options)
  console.log(stat);
});

cpd.on(END_EVENT, (clones: IClone[]) => {
  // detection process finished
  console.log(clones);
});

cpd.detect(code, { id: 'test', format: 'markup' })
  .then((clones: IClone[]) => console.log(clones));


cpd.detectInFiles(['./src', './tests'])
  .then((clones: IClone[]) => console.log(clones));

Progamming API

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MIT © Andrey Kucherenko