base on Code coverage for Ruby with a powerful configuration library and automatic merging of coverage across test suites SimpleCov [](https://badge.fury.io/rb/simplecov) [][Continuous Integration] [](https://codeclimate.com/github/simplecov-ruby/simplecov/maintainability) [](http://inch-ci.org/github/simplecov-ruby/simplecov) ========= **Code coverage for Ruby** * [Source Code] * [API documentation] * [Changelog] * [Rubygem] * [Continuous Integration] [Coverage]: https://docs.ruby-lang.org/en/3.2/Coverage.html "API doc for Ruby's Coverage library" [Source Code]: https://github.com/simplecov-ruby/simplecov "Source Code @ GitHub" [API documentation]: http://rubydoc.info/gems/simplecov/frames "RDoc API Documentation at Rubydoc.info" [Configuration]: http://rubydoc.info/gems/simplecov/SimpleCov/Configuration "Configuration options API documentation" [Changelog]: https://github.com/simplecov-ruby/simplecov/blob/main/CHANGELOG.md "Project Changelog" [Rubygem]: http://rubygems.org/gems/simplecov "SimpleCov @ rubygems.org" [Continuous Integration]: https://github.com/simplecov-ruby/simplecov/actions?query=workflow%3Astable "SimpleCov is built around the clock by github.com" [Dependencies]: https://gemnasium.com/simplecov-ruby/simplecov "SimpleCov dependencies on Gemnasium" [simplecov-html]: https://github.com/simplecov-ruby/simplecov-html "SimpleCov HTML Formatter Source Code @ GitHub" SimpleCov is a code coverage analysis tool for Ruby. It uses [Ruby's built-in Coverage][Coverage] library to gather code coverage data, but makes processing its results much easier by providing a clean API to filter, group, merge, format, and display those results, giving you a complete code coverage suite that can be set up with just a couple lines of code. SimpleCov/Coverage track covered ruby code, gathering coverage for common templating solutions like erb, slim and haml is not supported. In most cases, you'll want overall coverage results for your projects, including all types of tests, Cucumber features, etc. SimpleCov automatically takes care of this by caching and merging results when generating reports, so your report actually includes coverage across your test suites and thereby gives you a better picture of blank spots. The official formatter of SimpleCov is packaged as a separate gem called [simplecov-html], but will be installed and configured automatically when you launch SimpleCov. If you're curious, you can find it [on GitHub, too][simplecov-html]. ## Contact *Code and Bug Reports* * [Issue Tracker](https://github.com/simplecov-ruby/simplecov/issues) * See [CONTRIBUTING](https://github.com/simplecov-ruby/simplecov/blob/main/CONTRIBUTING.md) for how to contribute along with some common problems to check out before creating an issue. *Questions, Problems, Suggestions, etc.* * [Mailing List](https://groups.google.com/forum/#!forum/simplecov) "Open mailing list for discussion and announcements on Google Groups" Getting started --------------- 1. Add SimpleCov to your `Gemfile` and `bundle install`: ```ruby gem 'simplecov', require: false, group: :test ``` 2. Load and launch SimpleCov **at the very top** of your `test/test_helper.rb` (*or `spec_helper.rb`, `rails_helper`, cucumber `env.rb`, or whatever your preferred test framework uses*): ```ruby require 'simplecov' SimpleCov.start # Previous content of test helper now starts here ``` **Note:** If SimpleCov starts after your application code is already loaded (via `require`), it won't be able to track your files and their coverage! The `SimpleCov.start` **must** be issued **before any of your application code is required!** This is especially true if you use anything that keeps your tests application loaded like spring, check out the **[spring section](#want-to-use-spring-with-simplecov)**. SimpleCov must be running in the process that you want the code coverage analysis to happen on. When testing a server process (e.g. a JSON API endpoint) via a separate test process (e.g. when using Selenium) where you want to see all code executed by the `rails server`, and not just code executed in your actual test files, you need to require SimpleCov in the server process. For rails for instance, you'll want to add something like this to the top of `bin/rails`, but below the "shebang" line (`#! /usr/bin/env ruby`) and after config/boot is required: ```ruby if ENV['RAILS_ENV'] == 'test' require 'simplecov' SimpleCov.start 'rails' puts "required simplecov" end ``` 3. Run your full test suite to see the percent coverage that your application has. 4. After running your tests, open `coverage/index.html` in the browser of your choice. For example, in a Mac Terminal, run the following command from your application's root directory: ``` open coverage/index.html ``` in a debian/ubuntu Terminal, ``` xdg-open coverage/index.html ``` **Note:** [This guide](https://dwheeler.com/essays/open-files-urls.html) can help if you're unsure which command your particular operating system requires. 5. Add the following to your `.gitignore` file to ensure that coverage results are not tracked by Git (optional): ``` echo coverage >> .gitignore ``` If you're making a Rails application, SimpleCov comes with built-in configurations (see below for information on profiles) that will get you started with groups for your Controllers, Models and Helpers. To use it, the first two lines of your test_helper should be like this: ```ruby require 'simplecov' SimpleCov.start 'rails' ``` ## Example output **Coverage results report, fully browsable locally with sorting and much more:**  **Source file coverage details view:**  ## Use it with any framework! Similarly to the usage with Test::Unit described above, the only thing you have to do is to add the SimpleCov config to the very top of your Cucumber/RSpec/whatever setup file. Add the setup code to the **top** of `features/support/env.rb` (for Cucumber) or `spec/spec_helper.rb` (for RSpec). Other test frameworks should work accordingly, whatever their setup file may be: ```ruby require 'simplecov' SimpleCov.start 'rails' ``` You could even track what kind of code your UI testers are touching if you want to go overboard with things. SimpleCov does not care what kind of framework it is running in; it just looks at what code is being executed and generates a report about it. ### Notes on specific frameworks and test utilities For some frameworks and testing tools there are quirks and problems you might want to know about if you want to use SimpleCov with them. Here's an overview of the known ones: <table> <tr><th>Framework</th><th>Notes</th><th>Issue</th></tr> <tr> <th> parallel_tests </th> <td> As of 0.8.0, SimpleCov should correctly recognize parallel_tests and supplement your test suite names with their corresponding test env numbers. SimpleCov locks the resultset cache while merging, ensuring no race conditions occur when results are merged. </td> <td> <a href="https://github.com/simplecov-ruby/simplecov/issues/64">#64</a> &amp; <a href="https://github.com/simplecov-ruby/simplecov/pull/185">#185</a> </td> </tr> <tr> <th> knapsack_pro </th> <td> To make SimpleCov work with Knapsack Pro Queue Mode to split tests in parallel on CI jobs you need to provide CI node index number to the <code>SimpleCov.command_name</code> in <code>KnapsackPro::Hooks::Queue.before_queue</code> hook. </td> <td> <a href="https://knapsackpro.com/faq/question/how-to-use-simplecov-in-queue-mode">Tip</a> </td> </tr> <tr> <th> RubyMine </th> <td> The <a href="https://www.jetbrains.com/ruby/">RubyMine IDE</a> has built-in support for SimpleCov's coverage reports, though you might need to explicitly set the output root using `SimpleCov.root('foo/bar/baz')` </td> <td> <a href="https://github.com/simplecov-ruby/simplecov/issues/95">#95</a> </td> </tr> <tr> <th> Spork </th> <td> Because of how Spork works internally (using preforking), there used to be trouble when using SimpleCov with it, but that has apparently been resolved with a specific configuration strategy. See <a href="https://github.com/simplecov-ruby/simplecov/issues/42#issuecomment-4440284">this</a> comment. </td> <td> <a href="https://github.com/simplecov-ruby/simplecov/issues/42#issuecomment-4440284">#42</a> </td> </tr> <tr> <th> Spring </th> <td> <a href="#want-to-use-spring-with-simplecov">See section below.</a> </td> <td> <a href="https://github.com/simplecov-ruby/simplecov/issues/381">#381</a> </td> </tr> <tr> <th> Test/Unit </th> <td> Test Unit 2 used to mess with ARGV, leading to a failure to detect the test process name in SimpleCov. <code>test-unit</code> releases 2.4.3+ (Dec 11th, 2011) should have this problem resolved. </td> <td> <a href="https://github.com/simplecov-ruby/simplecov/issues/45">#45</a> &amp; <a href="https://github.com/test-unit/test-unit/pull/12">test-unit/test-unit#12</a> </td> </tr> </table> ## Configuring SimpleCov [Configuration] settings can be applied in three formats, which are completely equivalent: * The most common way is to configure it directly in your start block: ```ruby SimpleCov.start do some_config_option 'foo' end ``` * You can also set all configuration options directly: ```ruby SimpleCov.some_config_option 'foo' ``` * If you do not want to start coverage immediately after launch or want to add additional configuration later on in a concise way, use: ```ruby SimpleCov.configure do some_config_option 'foo' end ``` Please check out the [Configuration] API documentation to find out what you can customize. ## Using .simplecov for centralized config If you use SimpleCov to merge multiple test suite results (e.g. Test/Unit and Cucumber) into a single report, you'd normally have to set up all your config options twice, once in `test_helper.rb` and once in `env.rb`. To avoid this, you can place a file called `.simplecov` in your project root. You can then just leave the `require 'simplecov'` in each test setup helper (**at the top**) and move the `SimpleCov.start` code with all your custom config options into `.simplecov`: ```ruby # test/test_helper.rb require 'simplecov' # features/support/env.rb require 'simplecov' # .simplecov SimpleCov.start 'rails' do # any custom configs like groups and filters can be here at a central place end ``` Using `.simplecov` rather than separately requiring SimpleCov multiple times is recommended if you are merging multiple test frameworks like Cucumber and RSpec that rely on each other, as invoking SimpleCov multiple times can cause coverage information to be lost. ## Branch coverage (ruby "~> 2.5") Add branch coverage measurement statistics to your results. Supported in CRuby versions 2.5+. ```ruby SimpleCov.start do enable_coverage :branch end ``` Branch coverage is a feature introduced in Ruby 2.5 concerning itself with whether a particular branch of a condition had been executed. Line coverage on the other hand is only interested in whether a line of code has been executed. This comes in handy for instance for one line conditionals: ```ruby number.odd? ? "odd" : "even" ``` In line coverage this line would always be marked as executed but you'd never know if both conditions were met. Guard clauses have a similar story: ```ruby return if number.odd? # more code ``` If all the code in that method was covered you'd never know if the guard clause was ever triggered! With line coverage as just evaluating the condition marks it as covered. In the HTML report the lines of code will be annotated like `branch_type: hit_count`: * `then: 2` - the then branch (of an `if`) was executed twice * `else: 0` - the else branch (of an `if` or `case`) was never executed Not that even if you don't declare an `else` branch it will still show up in the coverage reports meaning that the condition of the `if` was not hit or that no `when` of `case` was hit during the test runs. **Is branch coverage strictly better?** No. Branch coverage really only concerns itself with conditionals - meaning coverage of sequential code is of no interest to it. A file without conditional logic will have no branch coverage data and SimpleCov will report 0 of 0 branches covered as 100% (as everything that can be covered was covered). Hence, we recommend looking at both metrics together. Branch coverage might also be a good overall metric to look at - while you might be missing only 10% of your lines that might account for 50% of your branches for instance. ## Primary Coverage By default, the primary coverage type is `line`. To set the primary coverage to something else, use the following: ```ruby # or in configure SimpleCov.primary_coverage :branch SimpleCov.start do enable_coverage :branch primary_coverage :branch end ``` Primary coverage determines what will come first in all output, and the type of coverage to check if you don't specify the type of coverage when customizing exit behavior (`SimpleCov.minimum_coverage 90`). Note that coverage must first be enabled for non-default coverage types. ## Coverage for eval You can measure coverage for code that is evaluated by `Kernel#eval`. Supported in CRuby versions 3.2+. ```ruby SimpleCov.start do enable_coverage_for_eval end ``` This is typically useful for ERB. Set `ERB#filename=` to make it possible for SimpleCov to trace the original .erb source file. ## Filters Filters can be used to remove selected files from your coverage data. By default, a filter is applied that removes all files OUTSIDE of your project's root directory - otherwise you'd end up with billions of coverage reports for source files in the gems you are using. You can define your own to remove things like configuration files, tests or whatever you don't need in your coverage report. ### Defining custom filters You can currently define a filter using either a String or Regexp (that will then be Regexp-matched against each source file's path), a block or by passing in your own Filter class. #### String filter ```ruby SimpleCov.start do add_filter "/test/" end ``` This simple string filter will remove all files that match "/test/" in their path. #### Regex filter ```ruby SimpleCov.start do add_filter %r{^/test/} end ``` This simple regex filter will remove all files that start with /test/ in their path. #### Block filter ```ruby SimpleCov.start do add_filter do |source_file| source_file.lines.count < 5 end end ``` Block filters receive a SimpleCov::SourceFile instance and expect your block to return either true (if the file is to be removed from the result) or false (if the result should be kept). Please check out the RDoc for SimpleCov::SourceFile to learn about the methods available to you. In the above example, the filter will remove all files that have less than 5 lines of code. #### Custom filter class ```ruby class LineFilter < SimpleCov::Filter def matches?(source_file) source_file.lines.count < filter_argument end end SimpleCov.add_filter LineFilter.new(5) ``` Defining your own filters is pretty easy: Just inherit from SimpleCov::Filter and define a method 'matches?(source_file)'. When running the filter, a true return value from this method will result in the removal of the given source_file. The filter_argument method is being set in the SimpleCov::Filter initialize method and thus is set to 5 in this example. #### Array filter ```ruby SimpleCov.start do proc = Proc.new { |source_file| false } add_filter ["string", /regex/, proc, LineFilter.new(5)] end ``` You can pass in an array containing any of the other filter types. #### Ignoring/skipping code You can exclude code from the coverage report by wrapping it in `# :nocov:`. ```ruby # :nocov: def skip_this_method never_reached end # :nocov: ``` The name of the token can be changed to your liking. [Learn more about the nocov feature.]( https://github.com/simplecov-ruby/simplecov/blob/main/features/config_nocov_token.feature) **Note:** You shouldn't have to use the nocov token to skip private methods that are being included in your coverage. If you appropriately test the public interface of your classes and objects you should automatically get full coverage of your private methods. ## Default root filter and coverage for things outside of it By default, SimpleCov filters everything outside of the `SimpleCov.root` directory. However, sometimes you may want to include coverage reports for things you include as a gem, for example a Rails Engine. Here's an example by [@lsaffie](https://github.com/lsaffie) from [#221](https://github.com/simplecov-ruby/simplecov/issues/221) that shows how you can achieve just that: ```ruby SimpleCov.start :rails do filters.clear # This will remove the :root_filter and :bundler_filter that come via simplecov's defaults add_filter do |src| !(src.filename =~ /^#{SimpleCov.root}/) unless src.filename =~ /my_engine/ end end ``` ## Groups You can separate your source files into groups. For example, in a Rails app, you'll want to have separate listings for Models, Controllers, Helpers, and Libs. Group definition works similarly to Filters (and also accepts custom filter classes), but source files end up in a group when the filter passes (returns true), as opposed to filtering results, which exclude files from results when the filter results in a true value. Add your groups with: ```ruby SimpleCov.start do add_group "Models", "app/models" add_group "Controllers", "app/controllers" add_group "Long files" do |src_file| src_file.lines.count > 100 end add_group "Multiple Files", ["app/models", "app/controllers"] # You can also pass in an array add_group "Short files", LineFilter.new(5) # Using the LineFilter class defined in Filters section above end ``` ## Merging results You normally want to have your coverage analyzed across ALL of your test suites, right? Simplecov automatically caches coverage results in your (coverage_path)/.resultset.json, and will merge or override those with subsequent runs, depending on whether simplecov considers those subsequent runs as different test suites or as the same test suite as the cached results. To make this distinction, simplecov has the concept of "test suite names". ### Test suite names SimpleCov tries to guess the name of the currently running test suite based upon the shell command the tests are running on. This should work fine for Unit Tests, RSpec, and Cucumber. If it fails, it will use the shell command that invoked the test suite as a command name. If you have some non-standard setup and still want nicely labeled test suites, you have to give Simplecov a cue as to what the name of the currently running test suite is. You can do so by specifying `SimpleCov.command_name` in one test file that is part of your specific suite. To customize the suite names on a Rails app (yeah, sorry for being Rails-biased, but everyone knows what the structure of those projects is. You can apply this accordingly to the RSpecs in your Outlook-WebDAV-Calendar-Sync gem), you could do something like this: ```ruby # test/unit/some_test.rb SimpleCov.command_name 'test:units' # test/functionals/some_controller_test.rb SimpleCov.command_name "test:functionals" # test/integration/some_integration_test.rb SimpleCov.command_name "test:integration" # features/support/env.rb SimpleCov.command_name "features" ``` Note that this only has to be invoked ONCE PER TEST SUITE, so even if you have 200 unit test files, specifying it in `some_test.rb` is enough. Last but not least **if multiple suites resolve to the same `command_name`** be aware that the coverage results **will clobber each other instead of being merged**. SimpleCov is smart enough to detect unique names for the most common setups, but if you have more than one test suite that doesn't follow a common pattern then you will want to manually ensure that each suite gets a unique `command_name`. If you are running tests in parallel each process has the potential to clobber results from the other test processes. If you are relying on the default `command_name` then SimpleCov will attempt to detect and avoid parallel test suite `command_name` collisions based on the presence of `ENV['PARALLEL_TEST_GROUPS']` and `ENV['TEST_ENV_NUMBER']`. If your parallel test runner does not set one or both of these then *you must* set a `command_name` and ensure that it is unique per process (eg. `command_name "Unit Tests PID #{$$}"`). If you are using parallel_tests, you must incorporate `TEST_ENV_NUMBER` into the command name yourself, in order for SimpleCov to merge the results correctly. For example: ```ruby # spec/spec_helper.rb SimpleCov.command_name "features" + (ENV['TEST_ENV_NUMBER'] || '') ``` [simplecov-html] prints the used test suites in the footer of the generated coverage report. ### Merging test runs under the same execution environment Test results are automatically merged with previous runs in the same execution environment when generating the result, so when coverage is set up properly for Cucumber and your unit / functional / integration tests, all of those test suites will be taken into account when building the coverage report. #### Timeout for merge Of course, your cached coverage data is likely to become invalid at some point. Thus, when automatically merging subsequent test runs, result sets that are older than `SimpleCov.merge_timeout` will not be used any more. By default, the timeout is 600 seconds (10 minutes), and you can raise (or lower) it by specifying `SimpleCov.merge_timeout 3600` (1 hour), or, inside a configure/start block, with just `merge_timeout 3600`. You can deactivate this automatic merging altogether with `SimpleCov.use_merging false`. ### Merging test runs under different execution environments If your tests are done in parallel across multiple build machines, you can fetch them all and merge them into a single result set using the `SimpleCov.collate` method. This can be added to a Rakefile or script file, having downloaded a set of `.resultset.json` files from each parallel test run. ```ruby # lib/tasks/coverage_report.rake namespace :coverage do desc "Collates all result sets generated by the different test runners" task :report do require 'simplecov' SimpleCov.collate Dir["simplecov-resultset-*/.resultset.json"] end end ``` `SimpleCov.collate` also takes an optional simplecov profile and an optional block for configuration, just the same as `SimpleCov.start` or `SimpleCov.configure`. This means you can configure a separate formatter for the collated output. For instance, you can make the formatter in `SimpleCov.start` the `SimpleCov::Formatter::SimpleFormatter`, and only use more complex formatters in the final `SimpleCov.collate` run. ```ruby # spec/spec_helper.rb require 'simplecov' SimpleCov.start 'rails' do # Disambiguates individual test runs command_name "Job #{ENV["TEST_ENV_NUMBER"]}" if ENV["TEST_ENV_NUMBER"] if ENV['CI'] formatter SimpleCov::Formatter::SimpleFormatter else formatter SimpleCov::Formatter::MultiFormatter.new([ SimpleCov::Formatter::SimpleFormatter, SimpleCov::Formatter::HTMLFormatter ]) end track_files "**/*.rb" end ``` ```ruby # lib/tasks/coverage_report.rake namespace :coverage do task :report do require 'simplecov' SimpleCov.collate Dir["simplecov-resultset-*/.resultset.json"], 'rails' do formatter SimpleCov::Formatter::MultiFormatter.new([ SimpleCov::Formatter::SimpleFormatter, SimpleCov::Formatter::HTMLFormatter ]) end end end ``` ## Running simplecov against subprocesses `SimpleCov.enable_for_subprocesses` will allow SimpleCov to observe subprocesses starting using `Process.fork`. This modifies ruby's core Process.fork method so that SimpleCov can see into it, appending `" (subprocess #{pid})"` to the `SimpleCov.command_name`, with results that can be merged together using SimpleCov's merging feature. To configure this, use `.at_fork`. ```ruby SimpleCov.enable_for_subprocesses true SimpleCov.at_fork do |pid| # This needs a unique name so it won't be overwritten SimpleCov.command_name "#{SimpleCov.command_name} (subprocess: #{pid})" # be quiet, the parent process will be in charge of output and checking coverage totals SimpleCov.print_error_status = false SimpleCov.formatter SimpleCov::Formatter::SimpleFormatter SimpleCov.minimum_coverage 0 # start SimpleCov.start end ``` NOTE: SimpleCov must have already been started before `Process.fork` was called. ### Running simplecov against spawned subprocesses Perhaps you're testing a ruby script with `PTY.spawn` or `Open3.popen`, or `Process.spawn` or etc. SimpleCov can cover this too. Add a .simplecov_spawn.rb file to your project root ```ruby # .simplecov_spawn.rb require 'simplecov' # this will also pick up whatever config is in .simplecov # so ensure it just contains configuration, and doesn't call SimpleCov.start. SimpleCov.command_name 'spawn' # As this is not for a test runner directly, script doesn't have a pre-defined base command_name SimpleCov.at_fork.call(Process.pid) # Use the per-process setup described previously SimpleCov.start # only now can we start. ``` Then, instead of calling your script directly, like: ```ruby PTY.spawn('my_script.rb') do # ... ``` Use bin/ruby to require the new .simplecov_spawn file, then your script ```ruby PTY.spawn('ruby -r./.simplecov_spawn my_script.rb') do # ... ``` ## Running coverage only on demand The Ruby STDLIB Coverage library that SimpleCov builds upon is *very* fast (on a ~10 min Rails test suite, the speed drop was only a couple seconds for me), and therefore it's SimpleCov's policy to just generate coverage every time you run your tests because it doesn't do your test speed any harm and you're always equipped with the latest and greatest coverage results. Because of this, SimpleCov has no explicit built-in mechanism to run coverage only on demand. However, you can still accomplish this very easily by introducing an ENV variable conditional into your SimpleCov setup block, like this: ```ruby SimpleCov.start if ENV["COVERAGE"] ``` Then, SimpleCov will only run if you execute your tests like this: ```shell COVERAGE=true rake test ``` ## Errors and exit statuses To aid in debugging issues, if an error is raised, SimpleCov will print a message to `STDERR` with the exit status of the error, like: ``` SimpleCov failed with exit 1 ``` This `STDERR` message can be disabled with: ``` SimpleCov.print_error_status = false ``` ## Profiles By default, SimpleCov's only config assumption is that you only want coverage reports for files inside your project root. To save yourself from repetitive configuration, you can use predefined blocks of configuration, called 'profiles', or define your own. You can then pass the name of the profile to be used as the first argument to SimpleCov.start. For example, simplecov comes bundled with a 'rails' profile. It looks somewhat like this: ```ruby SimpleCov.profiles.define 'rails' do add_filter '/test/' add_filter '/config/' add_group 'Controllers', 'app/controllers' add_group 'Models', 'app/models' add_group 'Helpers', 'app/helpers' add_group 'Libraries', 'lib' end ``` As you can see, it's just a SimpleCov.configure block. In your test_helper.rb, launch SimpleCov with: ```ruby SimpleCov.start 'rails' ``` or ```ruby SimpleCov.start 'rails' do # additional config here end ``` ### Custom profiles You can load additional profiles with the SimpleCov.load_profile('xyz') method. This allows you to build upon an existing profile and customize it so you can reuse it in unit tests and Cucumber features. For example: ```ruby # lib/simplecov_custom_profile.rb require 'simplecov' SimpleCov.profiles.define 'myprofile' do load_profile 'rails' add_filter 'vendor' # Don't include vendored stuff end # features/support/env.rb require 'simplecov_custom_profile' SimpleCov.start 'myprofile' # test/test_helper.rb require 'simplecov_custom_profile' SimpleCov.start 'myprofile' ``` ## Customizing exit behaviour You can define what SimpleCov should do when your test suite finishes by customizing the at_exit hook: ```ruby SimpleCov.at_exit do SimpleCov.result.format! end ``` Above is the default behaviour. Do whatever you like instead! ### Minimum coverage You can define the minimum coverage percentage expected. SimpleCov will return non-zero if unmet. ```ruby SimpleCov.minimum_coverage 90 # same as above (the default is to check line coverage) SimpleCov.minimum_coverage line: 90 # check for a minimum line coverage of 90% and minimum 80% branch coverage SimpleCov.minimum_coverage line: 90, branch: 80 ``` ### Minimum coverage by file You can define the minimum coverage by file percentage expected. SimpleCov will return non-zero if unmet. This is useful to help ensure coverage is relatively consistent, rather than being skewed by particularly good or bad areas of the code. ```ruby SimpleCov.minimum_coverage_by_file 80 # same as above (the default is to check line coverage by file) SimpleCov.minimum_coverage_by_file line: 80 # check for a minimum line coverage by file of 90% and minimum 80% branch coverage SimpleCov.minimum_coverage_by_file line: 90, branch: 80 ``` ### Maximum coverage drop You can define the maximum coverage drop percentage at once. SimpleCov will return non-zero if exceeded. ```ruby SimpleCov.maximum_coverage_drop 5 # same as above (the default is to check line drop) SimpleCov.maximum_coverage_drop line: 5 # check for a maximum line drop of 5% and maximum 10% branch drop SimpleCov.maximum_coverage_drop line: 5, branch: 10 ``` ### Refuse dropping coverage You can also entirely refuse dropping coverage between test runs: ```ruby SimpleCov.refuse_coverage_drop # same as above (the default is to only refuse line drop) SimpleCov.refuse_coverage_drop :line # refuse drop for line and branch SimpleCov.refuse_coverage_drop :line, :branch ``` ## Using your own formatter You can use your own formatter with: ```ruby SimpleCov.formatter = SimpleCov::Formatter::HTMLFormatter ``` Calling `SimpleCov.result.format!` will be invoked with `SimpleCov::Formatter::YourFormatter.new.format(result)`, and `result` is an instance of `SimpleCov::Result`. Do whatever your wish with that! ## Using multiple formatters As of SimpleCov 0.9, you can specify multiple result formats. Formatters besides the default HTML formatter require separate gems, however. ```ruby require "simplecov-html" SimpleCov.formatters = [ SimpleCov::Formatter::HTMLFormatter, SimpleCov::Formatter::CSVFormatter, ] ``` ## JSON formatter SimpleCov is packaged with a separate gem called [simplecov_json_formatter](https://github.com/codeclimate-community/simplecov_json_formatter) that provides you with a JSON formatter, this formatter could be useful for different use cases, such as for CI consumption or for reporting to external services. In order to use it you will need to manually load the installed gem like so: ```ruby require "simplecov_json_formatter" SimpleCov.formatter = SimpleCov::Formatter::JSONFormatter ``` > _Note:_ In case you plan to report your coverage results to CodeClimate services, know that SimpleCov will automatically use the > JSON formatter along with the HTML formatter when the `CC_TEST_REPORTER_ID` variable is present in the environment. ## Available formatters, editor integrations and hosted services * [Open Source formatter and integration plugins for SimpleCov](doc/alternate-formatters.md) * [Editor Integration](doc/editor-integration.md) * [Hosted (commercial) services](doc/commercial-services.md) ## Ruby version compatibility SimpleCov is built in [Continuous Integration] on Ruby 2.5+ as well as JRuby 9.2+. Note for JRuby => You need to pass JRUBY_OPTS="--debug" or create .jrubyrc and add debug.fullTrace=true ## Want to find dead code in production? Try [Coverband](https://github.com/danmayer/coverband). ## Want to use Spring with SimpleCov? If you're using [Spring](https://github.com/rails/spring) to speed up test suite runs and want to run SimpleCov along with them, you'll find that it often misreports coverage with the default config due to some sort of eager loading issue. Don't despair! One solution is to [explicitly call eager load](https://github.com/simplecov-ruby/simplecov/issues/381#issuecomment-347651728) in your `test_helper.rb` / `spec_helper.rb` after calling `SimpleCov.start`. ```ruby require 'simplecov' SimpleCov.start 'rails' Rails.application.eager_load! ``` Alternatively, you could disable Spring while running SimpleCov: ``` DISABLE_SPRING=1 rake test ``` Or you could remove `gem 'spring'` from your `Gemfile`. ## Troubleshooting The **most common problem is that simplecov isn't required and started before everything else**. In order to track coverage for your whole application **simplecov needs to be the first one** so that it (and the underlying coverage library) can subsequently track loaded files and their usage. If you are missing coverage for some code a simple trick is to put a puts statement in there and right after `SimpleCov.start` so you can see if the file really was loaded after simplecov was started. ```ruby # my_code.rb class MyCode puts "MyCode is being loaded!" def my_method # ... end end # spec_helper.rb/rails_helper.rb/test_helper.rb/.simplecov whatever SimpleCov.start puts "SimpleCov started successfully!" ``` Now when you run your test suite and you see: ``` SimpleCov started successfully! MyCode is being loaded! ``` then it's good otherwise you likely have a problem :) ## Code of Conduct Everyone participating in this project's development, issue trackers and other channels is expected to follow our [Code of Conduct](./CODE_OF_CONDUCT.md) ## Contributing See the [contributing guide](https://github.com/simplecov-ruby/simplecov/blob/main/CONTRIBUTING.md). ## Kudos Thanks to Aaron Patterson for the original idea for this! ## Copyright Copyright (c) 2010-2017 Christoph Olszowka. See MIT-LICENSE for details. ", Assign "at most 3 tags" to the expected json: {"id":"4212","tags":[]} "only from the tags list I provide: [{"id":77,"name":"3d"},{"id":89,"name":"agent"},{"id":17,"name":"ai"},{"id":54,"name":"algorithm"},{"id":24,"name":"api"},{"id":44,"name":"authentication"},{"id":3,"name":"aws"},{"id":27,"name":"backend"},{"id":60,"name":"benchmark"},{"id":72,"name":"best-practices"},{"id":39,"name":"bitcoin"},{"id":37,"name":"blockchain"},{"id":1,"name":"blog"},{"id":45,"name":"bundler"},{"id":58,"name":"cache"},{"id":21,"name":"chat"},{"id":49,"name":"cicd"},{"id":4,"name":"cli"},{"id":64,"name":"cloud-native"},{"id":48,"name":"cms"},{"id":61,"name":"compiler"},{"id":68,"name":"containerization"},{"id":92,"name":"crm"},{"id":34,"name":"data"},{"id":47,"name":"database"},{"id":8,"name":"declarative-gui "},{"id":9,"name":"deploy-tool"},{"id":53,"name":"desktop-app"},{"id":6,"name":"dev-exp-lib"},{"id":59,"name":"dev-tool"},{"id":13,"name":"ecommerce"},{"id":26,"name":"editor"},{"id":66,"name":"emulator"},{"id":62,"name":"filesystem"},{"id":80,"name":"finance"},{"id":15,"name":"firmware"},{"id":73,"name":"for-fun"},{"id":2,"name":"framework"},{"id":11,"name":"frontend"},{"id":22,"name":"game"},{"id":81,"name":"game-engine "},{"id":23,"name":"graphql"},{"id":84,"name":"gui"},{"id":91,"name":"http"},{"id":5,"name":"http-client"},{"id":51,"name":"iac"},{"id":30,"name":"ide"},{"id":78,"name":"iot"},{"id":40,"name":"json"},{"id":83,"name":"julian"},{"id":38,"name":"k8s"},{"id":31,"name":"language"},{"id":10,"name":"learning-resource"},{"id":33,"name":"lib"},{"id":41,"name":"linter"},{"id":28,"name":"lms"},{"id":16,"name":"logging"},{"id":76,"name":"low-code"},{"id":90,"name":"message-queue"},{"id":42,"name":"mobile-app"},{"id":18,"name":"monitoring"},{"id":36,"name":"networking"},{"id":7,"name":"node-version"},{"id":55,"name":"nosql"},{"id":57,"name":"observability"},{"id":46,"name":"orm"},{"id":52,"name":"os"},{"id":14,"name":"parser"},{"id":74,"name":"react"},{"id":82,"name":"real-time"},{"id":56,"name":"robot"},{"id":65,"name":"runtime"},{"id":32,"name":"sdk"},{"id":71,"name":"search"},{"id":63,"name":"secrets"},{"id":25,"name":"security"},{"id":85,"name":"server"},{"id":86,"name":"serverless"},{"id":70,"name":"storage"},{"id":75,"name":"system-design"},{"id":79,"name":"terminal"},{"id":29,"name":"testing"},{"id":12,"name":"ui"},{"id":50,"name":"ux"},{"id":88,"name":"video"},{"id":20,"name":"web-app"},{"id":35,"name":"web-server"},{"id":43,"name":"webassembly"},{"id":69,"name":"workflow"},{"id":87,"name":"yaml"}]" returns me the "expected json"