Section 57.5, “Project and task paths” starts with the following: >A project path has the following pattern: It starts always with a colon, which denotes the root project. The root project is the only project in a path that is not specified by its name. The rest of a project path is a colon-separated sequence of project names, where the next project is a subproject of the previous project.
In my experience, this is stricter than reality. I find that Gradle treats “docs:userguide” the same as “:docs:userguide”. Is it supposed to work this way, or is it supposed to work as written in the User Guide?