+fn create_alias_for_impl<F: FnMut(syn::ItemImpl, &mut TypeResolver)>(resolved_path: String, i: &syn::ItemImpl, types: &mut TypeResolver, mut callback: F) {
+ if let Some(aliases) = types.crate_types.reverse_alias_map.get(&resolved_path).cloned() {
+ let mut gen_types = Some(GenericTypes::new(Some(resolved_path.clone())));
+ if !gen_types.as_mut().unwrap().learn_generics(&i.generics, types) {
+ gen_types = None;
+ }
+ let alias_module = rsplit_once(&resolved_path, "::").unwrap().0;
+
+ 'alias_impls: for (alias_resolved, arguments) in aliases {
+ let mut new_ty_generics = Vec::new();
+ let mut new_ty_bounds = Vec::new();
+ let mut need_generics = false;
+
+ let alias_resolver_override;
+ let alias_resolver = if alias_module != types.module_path {
+ alias_resolver_override = ImportResolver::new(types.types.crate_name, &types.crate_types.lib_ast.dependencies,
+ alias_module, &types.crate_types.lib_ast.modules.get(alias_module).unwrap().items);
+ &alias_resolver_override
+ } else { &types.types };
+ let mut where_clause = syn::WhereClause { where_token: syn::Token![where](Span::call_site()),
+ predicates: syn::punctuated::Punctuated::new()
+ };
+ for (idx, gen) in i.generics.params.iter().enumerate() {
+ match gen {
+ syn::GenericParam::Type(type_param) => {
+ 'bounds_check: for bound in type_param.bounds.iter() {
+ if let syn::TypeParamBound::Trait(trait_bound) = bound {
+ if let syn::PathArguments::AngleBracketed(ref t) = &arguments {
+ assert!(idx < t.args.len());
+ if let syn::GenericArgument::Type(syn::Type::Path(p)) = &t.args[idx] {
+ let generic_bound = types.maybe_resolve_path(&trait_bound.path, None)
+ .unwrap_or_else(|| format!("{}::{}", types.module_path, single_ident_generic_path_to_ident(&trait_bound.path).unwrap()));
+
+ if let Some(generic_arg) = alias_resolver.maybe_resolve_path(&p.path, None) {
+ new_ty_generics.push((type_param.ident.clone(), syn::Type::Path(p.clone())));
+ if let Some(traits_impld) = types.crate_types.trait_impls.get(&generic_arg) {
+ for trait_impld in traits_impld {
+ if *trait_impld == generic_bound { continue 'bounds_check; }
+ }
+ eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
+ continue 'alias_impls;
+ } else {
+ eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
+ continue 'alias_impls;
+ }
+ } else if gen_types.is_some() {
+ let resp = types.maybe_resolve_path(&p.path, gen_types.as_ref());
+ if generic_bound == "core::ops::Deref" && resp.is_some() {
+ new_ty_bounds.push((type_param.ident.clone(),
+ string_path_to_syn_path("core::ops::Deref")));
+ let mut bounds = syn::punctuated::Punctuated::new();
+ bounds.push(syn::TypeParamBound::Trait(syn::TraitBound {
+ paren_token: None,
+ modifier: syn::TraitBoundModifier::None,
+ lifetimes: None,
+ path: string_path_to_syn_path(&types.resolve_path(&p.path, gen_types.as_ref())),
+ }));
+ let mut path = string_path_to_syn_path(&format!("{}::Target", type_param.ident));
+ path.leading_colon = None;
+ where_clause.predicates.push(syn::WherePredicate::Type(syn::PredicateType {
+ lifetimes: None,
+ bounded_ty: syn::Type::Path(syn::TypePath { qself: None, path }),
+ colon_token: syn::Token![:](Span::call_site()),
+ bounds,
+ }));
+ } else {
+ new_ty_generics.push((type_param.ident.clone(),
+ gen_types.as_ref().resolve_type(&syn::Type::Path(p.clone())).clone()));
+ }
+ need_generics = true;
+ } else {
+ unimplemented!();
+ }
+ } else { unimplemented!(); }
+ } else { unimplemented!(); }
+ } else { unimplemented!(); }
+ }
+ },
+ syn::GenericParam::Lifetime(_) => {},
+ syn::GenericParam::Const(_) => unimplemented!(),
+ }
+ }
+ let mut params = syn::punctuated::Punctuated::new();
+ let alias = string_path_to_syn_path(&alias_resolved);
+ let real_aliased =
+ if need_generics {
+ let alias_generics = types.crate_types.opaques.get(&alias_resolved).unwrap().1;
+
+ // If we need generics on the alias, create impl generic bounds...
+ assert_eq!(new_ty_generics.len() + new_ty_bounds.len(), i.generics.params.len());
+ let mut args = syn::punctuated::Punctuated::new();
+ for (ident, param) in new_ty_generics.drain(..) {
+ // TODO: We blindly assume that generics in the type alias and
+ // the aliased type have the same names, which we really shouldn't.
+ if alias_generics.params.iter().any(|generic|
+ if let syn::GenericParam::Type(t) = generic { t.ident == ident } else { false })
+ {
+ args.push(parse_quote!(#ident));
+ }
+ params.push(syn::GenericParam::Type(syn::TypeParam {
+ attrs: Vec::new(),
+ ident,
+ colon_token: None,
+ bounds: syn::punctuated::Punctuated::new(),
+ eq_token: Some(syn::token::Eq(Span::call_site())),
+ default: Some(param),
+ }));
+ }
+ for (ident, param) in new_ty_bounds.drain(..) {
+ // TODO: We blindly assume that generics in the type alias and
+ // the aliased type have the same names, which we really shouldn't.
+ if alias_generics.params.iter().any(|generic|
+ if let syn::GenericParam::Type(t) = generic { t.ident == ident } else { false })
+ {
+ args.push(parse_quote!(#ident));
+ }
+ params.push(syn::GenericParam::Type(syn::TypeParam {
+ attrs: Vec::new(),
+ ident,
+ colon_token: Some(syn::token::Colon(Span::call_site())),
+ bounds: syn::punctuated::Punctuated::from_iter(
+ Some(syn::TypeParamBound::Trait(syn::TraitBound {
+ path: param, paren_token: None, lifetimes: None,
+ modifier: syn::TraitBoundModifier::None,
+ }))
+ ),
+ eq_token: None,
+ default: None,
+ }));
+ }
+ // ... and swap the last segment of the impl self_ty to use the generic bounds.
+ let mut res = alias.clone();
+ res.segments.last_mut().unwrap().arguments = syn::PathArguments::AngleBracketed(syn::AngleBracketedGenericArguments {
+ colon2_token: None,
+ lt_token: syn::token::Lt(Span::call_site()),
+ args,
+ gt_token: syn::token::Gt(Span::call_site()),
+ });
+ res
+ } else { alias.clone() };
+ callback(syn::ItemImpl {
+ attrs: i.attrs.clone(),
+ brace_token: syn::token::Brace(Span::call_site()),
+ defaultness: None,
+ generics: syn::Generics {
+ lt_token: None,
+ params,
+ gt_token: None,
+ where_clause: Some(where_clause),
+ },
+ impl_token: syn::Token![impl](Span::call_site()),
+ items: i.items.clone(),
+ self_ty: Box::new(syn::Type::Path(syn::TypePath { qself: None, path: real_aliased })),
+ trait_: i.trait_.clone(),
+ unsafety: None,
+ }, types);
+ }
+ } else {
+ eprintln!("Not implementing anything for {} due to it being marked not exported", resolved_path);
+ }
+}
+
+/// Replaces upper case charachters with underscore followed by lower case except the first
+/// charachter and repeated upper case characthers (which are only made lower case).
+fn camel_to_snake_case(camel: &str) -> String {
+ let mut res = "".to_string();
+ let mut last_upper = -1;
+ for (idx, c) in camel.chars().enumerate() {
+ if c.is_uppercase() {
+ if last_upper != idx as isize - 1 { res.push('_'); }
+ res.push(c.to_lowercase().next().unwrap());
+ last_upper = idx as isize;
+ } else {
+ res.push(c);
+ }
+ }
+ res
+}
+