I would like to propose a new feature that can be bundled with Symfony: A command that can remove files that you don't need in production. There have been several suggestions in the past to not include things like tests when developing:

• [2.1] Exclude tests from zips via gitattributes #5674
• making use of .gitattributes #11810
• Removal of development & testing files using .gitattributes #16174
• [Suggestion] Adding .gitattributes to ignore unnecessary folders and files for production env #20057
• There are probably more..

I envision this as a command that people can add to their composer.json to remove:

• Test files/directories
• Docs (including images)
• md files (readme, upgrade, etc), might have to be optional

This should definitely not be removing source files like Tree Shaking! You can narrow your dependencies for that to specific components/bundles.

Several use-cases could be satisfied by this:

• Reducing the effective size of the application when using a buildserver or bundling Symfony in a desktop app /cc @jrobeson
• A clean environment when developing, no mocks or test files in auto-completion
• No readme files, examples or upgrade logs/contribution logs showing up in search results (hence this step might have to be optional).