bincode/derive

Bincode-derive

The derive crate for bincode. Implements bincode::Encode and bincode::Decode.

This crate is roughly split into 2 parts:

Parsing

Most of parsing is done in the src/parse/ folder. This will generate the following types:

• Attributes, not being used currently
• Visibility, not being used currently
• DataType either Struct or Enum, with the name of the data type being parsed
• Generics the generics part of the type, e.g. struct Foo<'a>
• GenericConstraints the "where" part of the type

Generate

Generating the code implementation is done in either src/derive_enum.rs and src/derive_struct.rs.

This is supported by the structs in src/generate. The most notable points of this module are:

• StreamBuilder is a thin but friendly wrapper around TokenStream
• Generator is the base type of the code generator. This has helper methods to generate implementations:
  • ImplFor is a helper struct for a single impl A for B construction. In this functions can be defined:
    • GenerateFnBody is a helper struct for a single function in the above impl. This is created with a callback to FnBuilder which helps set some properties. GenerateFnBody has a stream() function which returns StreamBuilder for the function.

For additional derive testing, see the test cases in ../tests

For testing purposes, all generated code is outputted to the current target/generated/bincode folder, under file name <struct/enum name>_Encode.rs and <struct/enum name>_Decode.rs. This can help with debugging.