RSG

Query rust source code using Xpath expressions

Installation

cargo install --git https://github.com/vickenty/rsg --branch main

Usage

rsg <xpath> [path]...

When no paths are given, reads from stdin. Path may be file or a directory.

Will print each matched item per line, serialized as a token stream.

Examples

Find all function signatures that accept a trait object:

$ rsg '//Signature[.//FnArg//TypeTraitObject]' src
src/main.rs: fn match_reader (r : & mut dyn Read , xpath : & str , name : & str) -> Result < () , Error >
src/lib.rs: fn add < F > (& mut self , name : & 'static str , item : Option < & 'ast dyn ToTokens > , f : F) where F : FnOnce (& mut Self) ,

Find all unwrap calls:

$ rsg '//ExprMethodCall[Ident="unwrap"]' src
src/lib.rs: el . attribute_value (ID_ATTR) . unwrap () . parse () . unwrap ()
src/lib.rs: v . root . unwrap ()
src/lib.rs: el . attribute_value (ID_ATTR) . unwrap ()
src/main.rs: types_builder . build () . unwrap ()
src/main.rs: paths . next () . unwrap ()
src/main.rs: matches . value_of ("expr") . unwrap ()
src/main.rs: match_reader (& mut std :: io :: stdin () . lock () , xpath , "<stdin>") . unwrap ()

How it works

rsg builds an XML document, where each of syn types is represented with an element of the same name. Identifiers have text content equal to the name of identifier.

Limitations

Does not show location of found items.
Only supports core Xpath 1.0.
Field names of syn structs are not represented in the XML document.

Contributing

Bug reports and merge requests are welcome.