tcount has the ability to count Tree-sitter queries (skim this first). These allow you to match patterns in the syntax tree for more fine grained counting.
Note: Simple queries can probably be replaced with --kind-pattern. (e.g. --kind-pattern=".*comment" usually suffices to count comments.)
To count a query named foo, pass the option --query=foo. If your query foo has capture groups bar and baz then these capture groups can instead be counted with --query=foo@bar,baz.
All queries are user-defined inside query directories. A query directory is a directory that contains subdirectories named for a specific language which themselves contain query files named {query}.scm files for each query. For example, a query directory could have a structure similar to:
query_directory/
├── rust/
│ ├── functions_query.scm
│ └── keywords_query.scm
├── ruby/
│ ├── functions_query.scm
│ └── keywords_query.scm
└── go
└── functions_query.scm
In the above query directory, we have a two queries functions_query (supports Rust, Ruby, and Go) and keywords_query (supports Rust and Ruby). If a language doesn't have a specific query file, then it will be counted as 0.
The language directories must be named according to third column in the output from --list-languages (e.g. C# queries go under c_sharp).
When --query=foo is used, tcount will begin looking for the foo query inside a query directory. When it find a foo query for any language, it will stop looking for other query directories and only languages with foo.scm in the current query directory will have the query counted.
When looking for a query directory with the query, the following locations will be searched:
$PWD/.tcount_queries/will be considered a query directory$XDG_CONFIG_HOME/tcount/*/will each (post-expansion) be considered query directories
There is no guarantee about the expansion order for #2 so conflicting queries results in undefined behaviour as to which is used.
The most important resource are the Tree-sitter Query Docs.
nvim-treesitter has a lot of queries that can be copy pasted.
Most parsers generated using Tree-sitter have a queries/ directory which have queries that can be copy pasted. For example, tree-sitter-go.