Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
typeck: move method errors/suggestions to their own file.
- Loading branch information
Showing
2 changed files
with
126 additions
and
101 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,122 @@ | ||
| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT | ||
| // file at the top-level directory of this distribution and at | ||
| // http://rust-lang.org/COPYRIGHT. | ||
| // | ||
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or | ||
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license | ||
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your | ||
| // option. This file may not be copied, modified, or distributed | ||
| // except according to those terms. | ||
|
|
||
| //! Give useful errors and suggestions to users when a method can't be | ||
| //! found or is otherwise invalid. | ||
|
|
||
| use astconv::AstConv; | ||
| use check::{self, FnCtxt}; | ||
| use middle::ty::{self, Ty}; | ||
| use util::ppaux::UserString; | ||
|
|
||
| use syntax::ast; | ||
| use syntax::codemap::Span; | ||
|
|
||
| use super::{MethodError, CandidateSource, impl_method, trait_method}; | ||
|
|
||
| pub fn report_error<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>, | ||
| span: Span, | ||
| rcvr_ty: Ty<'tcx>, | ||
| method_name: ast::Name, | ||
| error: MethodError) | ||
| { | ||
| match error { | ||
| MethodError::NoMatch(static_sources) => { | ||
| let cx = fcx.tcx(); | ||
| let method_ustring = method_name.user_string(cx); | ||
|
|
||
| // True if the type is a struct and contains a field with | ||
| // the same name as the not-found method | ||
| let is_field = match rcvr_ty.sty { | ||
| ty::ty_struct(did, _) => | ||
| ty::lookup_struct_fields(cx, did) | ||
| .iter() | ||
| .any(|f| f.name.user_string(cx) == method_ustring), | ||
| _ => false | ||
| }; | ||
|
|
||
| fcx.type_error_message( | ||
| span, | ||
| |actual| { | ||
| format!("type `{}` does not implement any \ | ||
| method in scope named `{}`", | ||
| actual, | ||
| method_ustring) | ||
| }, | ||
| rcvr_ty, | ||
| None); | ||
|
|
||
| // If the method has the name of a field, give a help note | ||
| if is_field { | ||
| cx.sess.span_note(span, | ||
| &format!("use `(s.{0})(...)` if you meant to call the \ | ||
| function stored in the `{0}` field", method_ustring)[]); | ||
| } | ||
|
|
||
| if static_sources.len() > 0 { | ||
| fcx.tcx().sess.fileline_note( | ||
| span, | ||
| "found defined static methods, maybe a `self` is missing?"); | ||
|
|
||
| report_candidates(fcx, span, method_name, static_sources); | ||
| } | ||
| } | ||
|
|
||
| MethodError::Ambiguity(sources) => { | ||
| span_err!(fcx.sess(), span, E0034, | ||
| "multiple applicable methods in scope"); | ||
|
|
||
| report_candidates(fcx, span, method_name, sources); | ||
| } | ||
| } | ||
|
|
||
| fn report_candidates(fcx: &FnCtxt, | ||
| span: Span, | ||
| method_name: ast::Name, | ||
| mut sources: Vec<CandidateSource>) { | ||
| sources.sort(); | ||
| sources.dedup(); | ||
|
|
||
| for (idx, source) in sources.iter().enumerate() { | ||
| match *source { | ||
| CandidateSource::ImplSource(impl_did) => { | ||
| // Provide the best span we can. Use the method, if local to crate, else | ||
| // the impl, if local to crate (method may be defaulted), else the call site. | ||
| let method = impl_method(fcx.tcx(), impl_did, method_name).unwrap(); | ||
| let impl_span = fcx.tcx().map.def_id_span(impl_did, span); | ||
| let method_span = fcx.tcx().map.def_id_span(method.def_id, impl_span); | ||
|
|
||
| let impl_ty = check::impl_self_ty(fcx, span, impl_did).ty; | ||
|
|
||
| let insertion = match ty::impl_trait_ref(fcx.tcx(), impl_did) { | ||
| None => format!(""), | ||
| Some(trait_ref) => format!(" of the trait `{}`", | ||
| ty::item_path_str(fcx.tcx(), | ||
| trait_ref.def_id)), | ||
| }; | ||
|
|
||
| span_note!(fcx.sess(), method_span, | ||
| "candidate #{} is defined in an impl{} for the type `{}`", | ||
| idx + 1u, | ||
| insertion, | ||
| impl_ty.user_string(fcx.tcx())); | ||
| } | ||
| CandidateSource::TraitSource(trait_did) => { | ||
| let (_, method) = trait_method(fcx.tcx(), trait_did, method_name).unwrap(); | ||
| let method_span = fcx.tcx().map.def_id_span(method.def_id, span); | ||
| span_note!(fcx.sess(), method_span, | ||
| "candidate #{} is defined in the trait `{}`", | ||
| idx + 1u, | ||
| ty::item_path_str(fcx.tcx(), trait_did)); | ||
| } | ||
| } | ||
| } | ||
| } | ||
| } |