src/librustc_trans/symbol_names_test.rs

   1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Walks the crate looking for items/impl-items/trait-items that have
  12 //! either a `rustc_symbol_name` or `rustc_item_path` attribute and
  13 //! generates an error giving, respectively, the symbol name or
  14 //! item-path. This is used for unit testing the code that generates
  15 //! paths etc in all kinds of annoying scenarios.
  16
  17 use back::symbol_names;
  18 use rustc::hir;
  19 use rustc::hir::intravisit::{self, Visitor};
  20 use syntax::ast;
  21 use syntax::attr::AttrMetaMethods;
  22
  23 use common::CrateContext;
  24 use monomorphize::Instance;
  25
  26 const SYMBOL_NAME: &'static str = "rustc_symbol_name";
  27 const ITEM_PATH: &'static str = "rustc_item_path";
  28
  29 pub fn report_symbol_names(ccx: &CrateContext) {
  30     // if the `rustc_attrs` feature is not enabled, then the
  31     // attributes we are interested in cannot be present anyway, so
  32     // skip the walk.
  33     let tcx = ccx.tcx();
  34     if !tcx.sess.features.borrow().rustc_attrs {
  35         return;
  36     }
  37
  38     let _ignore = tcx.dep_graph.in_ignore();
  39     let mut visitor = SymbolNamesTest { ccx: ccx };
  40     tcx.map.krate().visit_all_items(&mut visitor);
  41 }
  42
  43 struct SymbolNamesTest<'a, 'tcx:'a> {
  44     ccx: &'a CrateContext<'a, 'tcx>,
  45 }
  46
  47 impl<'a, 'tcx> SymbolNamesTest<'a, 'tcx> {
  48     fn process_attrs(&mut self,
  49                      node_id: ast::NodeId) {
  50         let tcx = self.ccx.tcx();
  51         let def_id = tcx.map.local_def_id(node_id);
  52         for attr in tcx.get_attrs(def_id).iter() {
  53             if attr.check_name(SYMBOL_NAME) {
  54                 // for now, can only use on monomorphic names
  55                 let instance = Instance::mono(self.ccx.shared(), def_id);
  56                 let name = symbol_names::exported_name(self.ccx, &instance);
  57                 tcx.sess.span_err(attr.span, &format!("symbol-name({})", name));
  58             } else if attr.check_name(ITEM_PATH) {
  59                 let path = tcx.item_path_str(def_id);
  60                 tcx.sess.span_err(attr.span, &format!("item-path({})", path));
  61             }
  62
  63             // (*) The formatting of `tag({})` is chosen so that tests can elect
  64             // to test the entirety of the string, if they choose, or else just
  65             // some subset.
  66         }
  67     }
  68 }
  69
  70 impl<'a, 'tcx> Visitor<'tcx> for SymbolNamesTest<'a, 'tcx> {
  71     fn visit_item(&mut self, item: &'tcx hir::Item) {
  72         self.process_attrs(item.id);
  73         intravisit::walk_item(self, item);
  74     }
  75
  76     fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
  77         self.process_attrs(ti.id);
  78         intravisit::walk_trait_item(self, ti)
  79     }
  80
  81     fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
  82         self.process_attrs(ii.id);
  83         intravisit::walk_impl_item(self, ii)
  84     }
  85 }
  86