Languages

Locus indexes by the final extension. The comparison is case-sensitive. .TS is not indexed. .ts does not include .tsx, .js does not include .jsx, and .h is not indexed at all.

Extension	Indexed	Symbols
.ts .tsx .js .jsx .mjs .cjs	Yes	Column-0 patterns only
.py	Yes	Column-0 patterns, including def and class
.md	Yes	The same column-0 patterns. Headings are not symbols
.rs	Yes	Column-0 patterns, plus indented fn, struct, enum, trait
.go	Yes	Column-0 patterns, plus indented func, including methods

Not indexed: .json, .yaml, .yml, .toml, .html, .css, .java, .c, .cpp, .h, .sh, .rb, .php, and everything else.

A filter uses the same final-extension rule. file_extensions: ["ts"] keeps src/app.ts and drops src/app.tsx. file_extensions: ["TS"] keeps nothing in a normal tree, because the indexed extension is lowercase ts.

file.tar.ts is indexed as ts. The filter token tar.ts is rejected during parsing. Filter with ts.

Skip rules are by directory name, not by language: node_modules, dist, target, .git.