RuboCop SketchUp

Gem Version Build status

Code analysis for SketchUp extensions using the SketchUp Ruby API.

Tool intended to assist with development of SketchUp extension by providing static analysis for common issues.



  • Standalone Ruby 2.2+ installation on the system. This is not intended to be used inside of SketchUp. Mac users should have Ruby already on the system, Windows users need to install it from

  • The RuboCop gem must also be installed.

    gem install rubocop -v 0.58.1


Install the rubocop-sketchup gem:

gem install rubocop-sketchup

Or, if you use bundler put this in your Gemfile:

gem 'rubocop-sketchup'


You need to tell RuboCop to load the rubocop-sketchup extension. There are three ways to do this:

RuboCop configuration file

Put this into your .rubocop.yml in your project root:

require: rubocop-sketchup

Now you can run rubocop and it will automatically load the RuboCop SketchUp cops together with the standard cops.

Running only cops for Extension Warehouse Technical requirements

If you want to focus on only the technical requirements for having your extension hosted on Extension Warehouse then you can limit the cop to only the SketchupRequirements department. This is the most important department which you should not ignore.

require: rubocop-sketchup

  DisabledByDefault: true

  Enabled: true

Running all SketchUp Cops

In addition to the requirements for the Extension Warehouse we have additional cops that looks for common patterns which have room for improvements. To run all of them, without all the RuboCop default cops use this configuration:

require: rubocop-sketchup

  DisabledByDefault: true

  Enabled: true

  Enabled: true

  Enabled: true

  Enabled: true

Source Path

By default rubocop-sketchup expects to find the source for the SketchUp extension within a src directory relative to your .rubocop.yml config file.

This can be configured to match your own project structure by overwriting AllCops/SketchUp/SourcePath in your .rubocop.yml:

    SourcePath: src

If this isn't configured correctly then some cops, such as SketchupRequirements/FileStructure will fail as extension file structure is part of the Extension Warehouse technical requirements. Additionally, SketchUp expects this particular file structure to fully manage the extension.

Target SketchUp Version

The SketchupSuggestions/Compatibility cop checks for usage of the SketchUp API against a configured target version.

Currently the default is SketchUp 2016.

rubocop --only SketchupSuggestions/Compatibility
Inspecting 30 files


examples/snippets/deprecations/compatibility.rb:9:13: C: SketchupSuggestions/Compatibility: The class Sketchup::ImageRep was added in SketchUp 2018 which is incompatible with target SketchUp 2014.
    image =
examples/snippets/deprecations/compatibility.rb:23:13: C: SketchupSuggestions/Compatibility: The constant Geom::PolygonMesh::MESH_POINTS was added in SketchUp 2018 which is incompatible with target SketchUp 2014.
    flags = Geom::PolygonMesh::MESH_POINTS | Geom::PolygonMesh::MESH_NORMALS
examples/snippets/deprecations/compatibility.rb:38:5: C: SketchupSuggestions/Compatibility: The method #onPidChanged was added in SketchUp 2017 which is incompatible with target SketchUp 2014.
    def onPidChanged(model, old_pid, new_pid) ...

30 files inspected, 3 offenses detected

This can be configured to match your own project structure by overwriting AllCops/SketchUp/SourcePath in your .rubocop.yml:

    TargetSketchUpVersion: 2016 M1

Available versions are:

2016 M1
8.0 M2
8.0 M1
7.1 M1
7.0 M1

Department Excludes

Current version of RuboCop doesn't support exclude filters for departments. To make it easier to exclude certain files for the SketchUp departments this can be configured in the SketchUp config section:

      - src/example/biz.rb
      - src/example/foo.rb
      - src/example/bar.rb
      - test/

Extra Details

Several cops have additional details to explain what they are checking. You can enable this by using the -D command line parameter or modifying your .rubocop.yml file by adding ExtraDetails: true under AllCops.

  ExtraDetails: true

Command line

rubocop --require rubocop-sketchup --only SketchupRequirements


RuboCop comes with a set of different formatters that let you control how the results are presented.

If you want to output the result in machine readable JSON;

rubocop --out results.json --format json

The rubocop-sketchup gem provides a custom formatter designed for SketchUp related cops. It explains which cops to focus your attention on.

rubocop -f extension_review -o report.html

See RuboCop's documentation for more examples.

Rake task do |task|
  task.requires << 'rubocop-sketchup'

The Cops

All cops are located under lib/rubocop/sketchup, and contain examples/documentation.


SketchupRequirements is the most important department. This one checks for the technical requirements that extensions need to meet in order to be hosted on Extension Warehouse. Address flagged issues from this department as soon as possible.

Note that the complete technical requirements for Extension Warehouse is not fully covered by these cops. But they get you a long way if you pass their control.


SketchupDeprecations is also an important department. Not rejection cause at Extension Warehouse, but worth paying attention to as it describe features of the API we would like to discourage the use of. Eventually some of them might be removed.


SketchupPerformance looks for common issues that impact performance. It's highly recommended to review what these cops report and evaluate if there are improvements that can be made to your extension.


SketchupSuggestions might be the more noisy of the departments. These are more general gentle suggestions for common improvements to raise the quality of your extension and source code. No need to address everything this reports, evaluate to the context of your extension. In general this department will be a collection of established best practices.


Development Requirements

Building this gem requires bundler.

gem install bundler

Initialize Developer Environment

From the folder where you cloned the repository:

bundle install

This will install all the developer dependencies to build the gem.


bundle exec rake install

After running this command rubocop-sketchup should be available on your system.


Running all tests:

bundle exec rake

Running single spec:

bundle exec rake spec SPEC=spec/rubocop/sketchup/requirements/global_methods_spec.rb


To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to

You need the API key for an account that have ownership of the gem to push a new version. Make sure the API key is set up in ~/.gem/credentials before running bundle exec rake release.

HTTPS GitHub Credentials under Windows

As of 22 Feb 2018, GitHub has disabled support for weak encryption which means many users will suddenly find themselves unable to authenticate using a Git for Windows which (impacts versions older than v2.16.0). DO NOT PANIC, there's a fix. Update Git for Windows to the latest (or at least v2.16.0).


  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request


rubocop-sketchup is MIT licensed.