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 rustc::hir;
  18 use rustc::hir::intravisit::{self, Visitor};
  19 use syntax::ast;
  20
  21 use common::SharedCrateContext;
  22 use monomorphize::Instance;
  23
  24 const SYMBOL_NAME: &'static str = "rustc_symbol_name";
  25 const ITEM_PATH: &'static str = "rustc_item_path";
  26
  27 pub fn report_symbol_names(scx: &SharedCrateContext) {
  28     // if the `rustc_attrs` feature is not enabled, then the
  29     // attributes we are interested in cannot be present anyway, so
  30     // skip the walk.
  31     let tcx = scx.tcx();
  32     if !tcx.sess.features.borrow().rustc_attrs {
  33         return;
  34     }
  35
  36     let _ignore = tcx.dep_graph.in_ignore();
  37     let mut visitor = SymbolNamesTest { scx: scx };
  38     tcx.map.krate().visit_all_items(&mut visitor);
  39 }
  40
  41 struct SymbolNamesTest<'a, 'tcx:'a> {
  42     scx: &'a SharedCrateContext<'a, 'tcx>,
  43 }
  44
  45 impl<'a, 'tcx> SymbolNamesTest<'a, 'tcx> {
  46     fn process_attrs(&mut self,
  47                      node_id: ast::NodeId) {
  48         let tcx = self.scx.tcx();
  49         let def_id = tcx.map.local_def_id(node_id);
  50         for attr in tcx.get_attrs(def_id).iter() {
  51             if attr.check_name(SYMBOL_NAME) {
  52                 // for now, can only use on monomorphic names
  53                 let instance = Instance::mono(self.scx, def_id);
  54                 let name = instance.symbol_name(self.scx);
  55                 tcx.sess.span_err(attr.span, &format!("symbol-name({})", name));
  56             } else if attr.check_name(ITEM_PATH) {
  57                 let path = tcx.item_path_str(def_id);
  58                 tcx.sess.span_err(attr.span, &format!("item-path({})", path));
  59             }
  60
  61             // (*) The formatting of `tag({})` is chosen so that tests can elect
  62             // to test the entirety of the string, if they choose, or else just
  63             // some subset.
  64         }
  65     }
  66 }
  67
  68 impl<'a, 'tcx> Visitor<'tcx> for SymbolNamesTest<'a, 'tcx> {
  69     fn visit_item(&mut self, item: &'tcx hir::Item) {
  70         self.process_attrs(item.id);
  71         intravisit::walk_item(self, item);
  72     }
  73
  74     fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
  75         self.process_attrs(ti.id);
  76         intravisit::walk_trait_item(self, ti)
  77     }
  78
  79     fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) {
  80         self.process_attrs(ii.id);
  81         intravisit::walk_impl_item(self, ii)
  82     }
  83 }
  84