Use `parse_quote!()` to build complex syn::* objects
[ldk-c-bindings] / c-bindings-gen / src / main.rs
index 0d002bbbeb40421598b34add308071dc7afe6532..e30bb160247b3de02957ec89b8192db38bfee53c 100644 (file)
@@ -25,6 +25,7 @@ use std::io::{Read, Write};
 use std::process;
 
 use proc_macro2::Span;
+use syn::parse_quote;
 
 mod types;
 mod blocks;
@@ -63,9 +64,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                                writeln!(w, "/// Serialize the {} object into a byte array which can be read by {}_read", for_obj, for_obj).unwrap();
                                writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, full_obj_path).unwrap();
 
-                               let ref_type = syn::Type::Reference(syn::TypeReference {
-                                       and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None,
-                                       elem: Box::new(for_ty.clone()) });
+                               let ref_type: syn::Type = syn::parse_quote!(&#for_ty);
                                assert!(!types.write_from_c_conversion_new_var(w, &syn::Ident::new("obj", Span::call_site()), &ref_type, Some(generics)));
 
                                write!(w, "\tcrate::c_types::serialize_obj(").unwrap();
@@ -84,26 +83,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                        },
                        "lightning::util::ser::Readable"|"lightning::util::ser::ReadableArgs" => {
                                // Create the Result<Object, DecodeError> syn::Type
-                               let mut err_segs = syn::punctuated::Punctuated::new();
-                               err_segs.push(syn::PathSegment { ident: syn::Ident::new("ln", Span::call_site()), arguments: syn::PathArguments::None });
-                               err_segs.push(syn::PathSegment { ident: syn::Ident::new("msgs", Span::call_site()), arguments: syn::PathArguments::None });
-                               err_segs.push(syn::PathSegment { ident: syn::Ident::new("DecodeError", Span::call_site()), arguments: syn::PathArguments::None });
-                               let mut args = syn::punctuated::Punctuated::new();
-                               args.push(syn::GenericArgument::Type(for_ty.clone()));
-                               args.push(syn::GenericArgument::Type(syn::Type::Path(syn::TypePath {
-                                       qself: None, path: syn::Path {
-                                               leading_colon: Some(syn::Token![::](Span::call_site())), segments: err_segs,
-                                       }
-                               })));
-                               let mut res_segs = syn::punctuated::Punctuated::new();
-                               res_segs.push(syn::PathSegment {
-                                       ident: syn::Ident::new("Result", Span::call_site()),
-                                       arguments: syn::PathArguments::AngleBracketed(syn::AngleBracketedGenericArguments {
-                                               colon2_token: None, lt_token: syn::Token![<](Span::call_site()), args, gt_token: syn::Token![>](Span::call_site()),
-                                       })
-                               });
-                               let res_ty = syn::Type::Path(syn::TypePath { qself: None, path: syn::Path {
-                                       leading_colon: None, segments: res_segs } });
+                               let res_ty: syn::Type = parse_quote!(Result<#for_ty, ::ln::msgs::DecodeError>);
 
                                writeln!(w, "#[no_mangle]").unwrap();
                                writeln!(w, "/// Read a {} from a byte array, created by {}_write", for_obj, for_obj).unwrap();
@@ -1300,8 +1280,9 @@ fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &
 /// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at
 /// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST
 /// at `module` from C.
-fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>, out_dir: &str, orig_crate: &str, header_file: &mut File, cpp_header_file: &mut File) {
+fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>, out_dir: &str, header_file: &mut File, cpp_header_file: &mut File) {
        for (module, astmod) in libast.modules.iter() {
+               let orig_crate = module.splitn(2, "::").next().unwrap();
                let ASTModule { ref attrs, ref items, ref submods } = astmod;
                assert_eq!(export_status(&attrs), ExportStatus::Export);
 
@@ -1454,10 +1435,11 @@ fn walk_private_mod<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, modul
 }
 
 /// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes.
-fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, crate_types: &mut CrateTypes<'a>) {
+fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) {
        for (module, astmod) in ast_storage.modules.iter() {
                let ASTModule { ref attrs, ref items, submods: _ } = astmod;
                assert_eq!(export_status(&attrs), ExportStatus::Export);
+               let orig_crate = module.splitn(2, "::").next().unwrap();
                let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, module, items);
 
                for item in items.iter() {
@@ -1573,17 +1555,17 @@ fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, crate_types:
 
 fn main() {
        let args: Vec<String> = env::args().collect();
-       if args.len() != 6 {
-               eprintln!("Usage: target/dir source_crate_name derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
+       if args.len() != 5 {
+               eprintln!("Usage: target/dir derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
                process::exit(1);
        }
 
        let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
-               .open(&args[3]).expect("Unable to open new header file");
+               .open(&args[2]).expect("Unable to open new header file");
        let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
-               .open(&args[4]).expect("Unable to open new header file");
+               .open(&args[3]).expect("Unable to open new header file");
        let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
-               .open(&args[5]).expect("Unable to open new header file");
+               .open(&args[4]).expect("Unable to open new header file");
 
        writeln!(header_file, "#if defined(__GNUC__)").unwrap();
        writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
@@ -1609,10 +1591,10 @@ fn main() {
        // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
        // when parsing other file ASTs...
        let mut libtypes = CrateTypes::new(&mut derived_templates, &libast);
-       walk_ast(&libast, &args[2], &mut libtypes);
+       walk_ast(&libast, &mut libtypes);
 
        // ... finally, do the actual file conversion/mapping, writing out types as we go.
-       convert_file(&libast, &libtypes, &args[1], &args[2], &mut header_file, &mut cpp_header_file);
+       convert_file(&libast, &libtypes, &args[1], &mut header_file, &mut cpp_header_file);
 
        // For container templates which we created while walking the crate, make sure we add C++
        // mapped types so that C++ users can utilize the auto-destructors available.