Template files have wrong file extension

It's pretty annoying that groovy scaffolding template files in src/main/templates have the file extension .groovy because IDEs assume they are groovy files and annoy you forever that their syntax is invalid. In point of fact, they are not groovy files, they are a mish mash of groovy and some other stuff. Just like Microsoft Excel templates have different file extension (.xlsx) compared to regular Excel files (.xls), these non-groovy half-groovy templates deserve their own file extension, such as .groovyt or something. I could say the same thing about .gsp template files, should be .gspt.

Who knows... if you differentiate them thus, Jetbrains might even write a syntax checker for them.

Start by inspecting the Groovy scaffolding templates under src/main/templates and tracing where their current .groovy and .gsp extensions are referenced. Decide the intended distinct extensions for these mixed-content templates, update the relevant references, and verify that regular Groovy and GSP files are not affected.

Written by the indexing model from the issue text.