Replace more manually-built `syn::Path` with `parse_quote!()`
[ldk-c-bindings] / c-bindings-gen / src / main.rs
index 0d002bbbeb40421598b34add308071dc7afe6532..d107f3e9a6c66af726c4c84602c45c209686712c 100644 (file)
@@ -25,6 +25,8 @@ use std::io::{Read, Write};
 use std::process;
 
 use proc_macro2::Span;
+use quote::format_ident;
+use syn::parse_quote;
 
 mod types;
 mod blocks;
@@ -63,10 +65,8 @@ 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()) });
-                               assert!(!types.write_from_c_conversion_new_var(w, &syn::Ident::new("obj", Span::call_site()), &ref_type, Some(generics)));
+                               let ref_type: syn::Type = syn::parse_quote!(&#for_ty);
+                               assert!(!types.write_from_c_conversion_new_var(w, &format_ident!("obj"), &ref_type, Some(generics)));
 
                                write!(w, "\tcrate::c_types::serialize_obj(").unwrap();
                                types.write_from_c_conversion_prefix(w, &ref_type, Some(generics));
@@ -84,26 +84,7 @@ 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();
@@ -120,7 +101,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                                                if let syn::GenericArgument::Type(args_ty) = args.args.iter().next().unwrap() {
                                                        types.write_c_type(w, args_ty, Some(generics), false);
 
-                                                       assert!(!types.write_from_c_conversion_new_var(&mut arg_conv, &syn::Ident::new("arg", Span::call_site()), &args_ty, Some(generics)));
+                                                       assert!(!types.write_from_c_conversion_new_var(&mut arg_conv, &format_ident!("arg"), &args_ty, Some(generics)));
 
                                                        write!(&mut arg_conv, "\tlet arg_conv = ").unwrap();
                                                        types.write_from_c_conversion_prefix(&mut arg_conv, &args_ty, Some(generics));
@@ -143,7 +124,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                                        writeln!(w, "\tlet res = crate::c_types::deserialize_obj(ser);").unwrap();
                                }
                                write!(w, "\t").unwrap();
-                               if types.write_to_c_conversion_new_var(w, &syn::Ident::new("res", Span::call_site()), &res_ty, Some(generics), false) {
+                               if types.write_to_c_conversion_new_var(w, &format_ident!("res"), &res_ty, Some(generics), false) {
                                        write!(w, "\n\t").unwrap();
                                }
                                types.write_to_c_conversion_inline_prefix(w, &res_ty, Some(generics), false);
@@ -622,7 +603,7 @@ fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct,
                                                write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, ident, struct_name).unwrap();
                                                types.write_c_type(w, &ref_type, Some(&gen_types), true);
                                                write!(w, " {{\n\tlet mut inner_val = &mut unsafe {{ &mut *this_ptr.inner }}.{};\n\t", ident).unwrap();
-                                               let local_var = types.write_to_c_conversion_new_var(w, &syn::Ident::new("inner_val", Span::call_site()), &ref_type, Some(&gen_types), true);
+                                               let local_var = types.write_to_c_conversion_new_var(w, &format_ident!("inner_val"), &ref_type, Some(&gen_types), true);
                                                if local_var { write!(w, "\n\t").unwrap(); }
                                                types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true);
                                                if local_var {
@@ -639,7 +620,7 @@ fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct,
                                                write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, ident, struct_name).unwrap();
                                                types.write_c_type(w, &field.ty, Some(&gen_types), false);
                                                write!(w, ") {{\n\t").unwrap();
-                                               let local_var = types.write_from_c_conversion_new_var(w, &syn::Ident::new("val", Span::call_site()), &field.ty, Some(&gen_types));
+                                               let local_var = types.write_from_c_conversion_new_var(w, &format_ident!("val"), &field.ty, Some(&gen_types));
                                                if local_var { write!(w, "\n\t").unwrap(); }
                                                write!(w, "unsafe {{ &mut *this_ptr.inner }}.{} = ", ident).unwrap();
                                                types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
@@ -662,8 +643,8 @@ fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct,
                        }
                        write!(w, ") -> {} {{\n\t", struct_name).unwrap();
                        for field in fields.named.iter() {
-                               let field_name = format!("{}_arg", field.ident.as_ref().unwrap());
-                               if types.write_from_c_conversion_new_var(w, &syn::Ident::new(&field_name, Span::call_site()), &field.ty, Some(&gen_types)) {
+                               let field_ident = format_ident!("{}_arg", field.ident.as_ref().unwrap());
+                               if types.write_from_c_conversion_new_var(w, &field_ident, &field.ty, Some(&gen_types)) {
                                        write!(w, "\n\t").unwrap();
                                }
                        }
@@ -1185,7 +1166,7 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type
                                                        if $ref {
                                                                write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", $field_ident, $field_ident).unwrap();
                                                                if new_var {
-                                                                       let nonref_ident = syn::Ident::new(&format!("{}_nonref", $field_ident), Span::call_site());
+                                                                       let nonref_ident = format_ident!("{}_nonref", $field_ident);
                                                                        if $to_c {
                                                                                types.write_to_c_conversion_new_var(w, &nonref_ident, &$field.ty, None, false);
                                                                        } else {
@@ -1207,7 +1188,7 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type
                                } else if let syn::Fields::Unnamed(fields) = &var.fields {
                                        write!(w, " {{\n\t\t\t\t").unwrap();
                                        for (idx, field) in fields.unnamed.iter().enumerate() {
-                                               handle_field_a!(field, &syn::Ident::new(&(('a' as u8 + idx as u8) as char).to_string(), Span::call_site()));
+                                               handle_field_a!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
                                        }
                                } else { write!(w, " ").unwrap(); }
 
@@ -1245,7 +1226,7 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type
                                        write!(w, " (").unwrap();
                                        for (idx, field) in fields.unnamed.iter().enumerate() {
                                                write!(w, "\n\t\t\t\t\t").unwrap();
-                                               handle_field_b!(field, &syn::Ident::new(&(('a' as u8 + idx as u8) as char).to_string(), Span::call_site()));
+                                               handle_field_b!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
                                        }
                                        writeln!(w, "\n\t\t\t\t)").unwrap();
                                        write!(w, "\t\t\t}}").unwrap();
@@ -1300,8 +1281,9 @@ 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 +1436,11 @@ 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() {
@@ -1503,20 +1486,17 @@ fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, crate_types:
                                                if process_alias {
                                                        match &*t.ty {
                                                                syn::Type::Path(p) => {
+                                                                       let t_ident = &t.ident;
+
                                                                        // If its a path with no generics, assume we don't map the aliased type and map it opaque
-                                                                       let mut segments = syn::punctuated::Punctuated::new();
-                                                                       segments.push(syn::PathSegment {
-                                                                               ident: t.ident.clone(),
-                                                                               arguments: syn::PathArguments::None,
-                                                                       });
-                                                                       let path_obj = syn::Path { leading_colon: None, segments };
+                                                                       let path_obj = parse_quote!(#t_ident);
                                                                        let args_obj = p.path.segments.last().unwrap().arguments.clone();
                                                                        match crate_types.reverse_alias_map.entry(import_resolver.maybe_resolve_path(&p.path, None).unwrap()) {
                                                                                hash_map::Entry::Occupied(mut e) => { e.get_mut().push((path_obj, args_obj)); },
                                                                                hash_map::Entry::Vacant(e) => { e.insert(vec![(path_obj, args_obj)]); },
                                                                        }
 
-                                                                       crate_types.opaques.insert(type_path.clone(), &t.ident);
+                                                                       crate_types.opaques.insert(type_path, t_ident);
                                                                },
                                                                _ => {
                                                                        crate_types.type_aliases.insert(type_path, import_resolver.resolve_imported_refs((*t.ty).clone()));
@@ -1573,17 +1553,17 @@ 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 +1589,10 @@ 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.