Add sensitivity to ARDUINO_CI_SELECT_CPP_TESTS to narrow the scope of rspec testing C++ files

Author: ianfixes

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 ### Added
+- Added rspec sensitivity to the environment variable `$ARDUINO_CI_SELECT_CPP_TESTS=<glob>` (for `arduino_ci` gem hackers)
 
 ### Changed
 - `CiConfig::allowable_unittest_files` now uses `Pathname` to full effect

CONTRIBUTING.md

@@ -32,8 +32,9 @@ To speed up testing by targeting only the files you're working on, you can set s
 * `ARDUINO_CI_SKIP_SPLASH_SCREEN_RSPEC_TESTS`: if set, this will avoid any rspec test that calls the arduino executable (and as such, causes the splash screen to pop up).
 * `ARDUINO_CI_SKIP_RUBY_RSPEC_TESTS`: if set, this will skip all tests against ruby code (useful if you are not changing Ruby code).
 * `ARDUINO_CI_SKIP_CPP_RSPEC_TESTS`: if set, this will skip all tests against the `TestSomething` sample project (useful if you are not changing C++ code).
+* `ARDUINO_CI_SELECT_CPP_TESTS=<glob>`: if set, this will skip all C++ unit tests whose filenames don't match the provided glob (executed in the tests directory)
 
-You can set them to any value, they just have to be set.  Example usage:
+Example usage:
 
 ```shell
 ARDUINO_CI_SKIP_RUBY_RSPEC_TESTS=1 bundle exec rspec

spec/testsomething_unittests_spec.rb

@@ -44,6 +44,14 @@ def get_relative_dir(sampleprojects_tests_dir)
     end
 
     test_files = config.allowable_unittest_files(cpp_library.test_files)
+
+    # filter the list based on a glob, if provided
+    unless ENV["ARDUINO_CI_SELECT_CPP_TESTS"].nil?
+      Dir.chdir(cpp_library.tests_dir) do
+        globbed = Pathname.glob(ENV["ARDUINO_CI_SELECT_CPP_TESTS"])
+        test_files.select! { |p| globbed.include?(p.basename) }
+      end
+    end
     test_files.each do |path|
       tfn = File.basename(path)