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jscoverage tool, both node.js or javascript support

Build Status NPM version


npm install jscoverage


from v0.5.0, jscoverage start using uglify2, and enhance the coverage range. now, jscoverage will find out which branch you missed!

Get start

using mocha loading the jscoverage module, then it's work:

mocha -r jscoverage test/

jscoverage will append coverage info when you select list or spec or tap reporter in mocha

mocha -r jscoverage -R spec test/

besides, you can use --covout to specify the reporter, like html, detail. the detail reporter will print the uncovered code in the console directly.

using jscoverage with mocha

full modelł:

mocha -r jscoverage --covignore .covignore --covout=html --covinject=true --coverage=90,85,75 test

the cmd above means:

  • mocha run test case with jscoverage module
  • jscoverage will ignore files while list in .covignore file
  • jscoverage will output a report in html format
  • jscoverage will inject a group of function to your module.exports (_get, _set, _reset, _replace);
  • jscoverage will switch the colorful output: 90%+ is greate, 85%+ is ok, lower then 75% coverage is terrible

jscoverage can recognise all options below:

 --covignore [filepath] # like gitignore, tell jscoverage to ignore these files
 --overrideIgnore [boolean] # set if override the build-in ignore rules
 --covout [output report] # can be:  spec, list, tap, detail, html
 --coverage [high,middle,low] # coverage level, default is: 90,70,30 , means 90% is high, 30% is low
 --covinject [boolean] # switch if inject code for easytest(exports._get, exports._replace, exports._reset)

default jscoverage will search .covignore in the project root

using jscoverage as cli command

# print help info 
jscoverage source.js
# convert source.js to source-cov.js 
jscoverage source.js dest.js
# convert source.js to dest.js 
jscoverage sourcedir destdir --exclude a.js,b.js,c.js,*.min.js
# convert all files in sourcedir to destdir, exclude list will be ignored 

jscoverage will copy exclude file from source dir to dest dir

using inject api for node.js test

var testMod = require('module/for/test.js');
testMod._replace('name', value);

inline ignore annotation

using bellow comment, jscoverage will ignore the following block/statement

  /* @covignore */

using jscoverage programmatically

comming soon

mocha global leaks detect

The follow object will be detected, all of them are created by jscoverage.

  • _$jscoverage
  • _$jscmd