You can manually select the project language in Bitbucket or use .gitattributes in GitHub.
Is there a way to get GitLab to assign a specific language to a project?
GitLab will adhere to the overrides specified in the .gitattributes file. GitLab currently uses the Linguist Gem . Without these overrides, Linguist will infer the main language used for the project by analyzing the code inside the files in the project.
You can find out how magic happens by referencing the Repository # main_language method in gitlab-ce .