src/librustc/plugin/registry.rs

   1 // Copyright 2012-2013 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 //! Used by plugin crates to tell `rustc` about the plugins they provide.
  12
  13 use lint::{LintPassObject, LintId, Lint};
  14 use session::Session;
  15
  16 use syntax::ext::base::{SyntaxExtension, NamedSyntaxExtension, NormalTT};
  17 use syntax::ext::base::{IdentTT, MultiModifier, MultiDecorator};
  18 use syntax::ext::base::{MacroExpanderFn, MacroRulesTT};
  19 use syntax::codemap::Span;
  20 use syntax::parse::token;
  21 use syntax::ptr::P;
  22 use syntax::ast;
  23 use syntax::feature_gate::AttributeType;
  24
  25 use std::collections::HashMap;
  26 use std::borrow::ToOwned;
  27
  28 /// Structure used to register plugins.
  29 ///
  30 /// A plugin registrar function takes an `&mut Registry` and should call
  31 /// methods to register its plugins.
  32 ///
  33 /// This struct has public fields and other methods for use by `rustc`
  34 /// itself. They are not documented here, and plugin authors should
  35 /// not use them.
  36 pub struct Registry<'a> {
  37     /// Compiler session. Useful if you want to emit diagnostic messages
  38     /// from the plugin registrar.
  39     pub sess: &'a Session,
  40
  41     #[doc(hidden)]
  42     pub args_hidden: Option<Vec<P<ast::MetaItem>>>,
  43
  44     #[doc(hidden)]
  45     pub krate_span: Span,
  46
  47     #[doc(hidden)]
  48     pub syntax_exts: Vec<NamedSyntaxExtension>,
  49
  50     #[doc(hidden)]
  51     pub lint_passes: Vec<LintPassObject>,
  52
  53     #[doc(hidden)]
  54     pub lint_groups: HashMap<&'static str, Vec<LintId>>,
  55
  56     #[doc(hidden)]
  57     pub llvm_passes: Vec<String>,
  58
  59     #[doc(hidden)]
  60     pub attributes: Vec<(String, AttributeType)>,
  61 }
  62
  63 impl<'a> Registry<'a> {
  64     #[doc(hidden)]
  65     pub fn new(sess: &'a Session, krate: &ast::Crate) -> Registry<'a> {
  66         Registry {
  67             sess: sess,
  68             args_hidden: None,
  69             krate_span: krate.span,
  70             syntax_exts: vec!(),
  71             lint_passes: vec!(),
  72             lint_groups: HashMap::new(),
  73             llvm_passes: vec!(),
  74             attributes: vec!(),
  75         }
  76     }
  77
  78     /// Get the plugin's arguments, if any.
  79     ///
  80     /// These are specified inside the `plugin` crate attribute as
  81     ///
  82     /// ```no_run
  83     /// #![plugin(my_plugin_name(... args ...))]
  84     /// ```
  85     pub fn args<'b>(&'b self) -> &'b Vec<P<ast::MetaItem>> {
  86         self.args_hidden.as_ref().expect("args not set")
  87     }
  88
  89     /// Register a syntax extension of any kind.
  90     ///
  91     /// This is the most general hook into `libsyntax`'s expansion behavior.
  92     #[allow(deprecated)]
  93     pub fn register_syntax_extension(&mut self, name: ast::Name, extension: SyntaxExtension) {
  94         self.syntax_exts.push((name, match extension {
  95             NormalTT(ext, _, allow_internal_unstable) => {
  96                 NormalTT(ext, Some(self.krate_span), allow_internal_unstable)
  97             }
  98             IdentTT(ext, _, allow_internal_unstable) => {
  99                 IdentTT(ext, Some(self.krate_span), allow_internal_unstable)
 100             }
 101             MultiDecorator(ext) => MultiDecorator(ext),
 102             MultiModifier(ext) => MultiModifier(ext),
 103             MacroRulesTT => {
 104                 self.sess.err("plugin tried to register a new MacroRulesTT");
 105                 return;
 106             }
 107         }));
 108     }
 109
 110     /// Register a macro of the usual kind.
 111     ///
 112     /// This is a convenience wrapper for `register_syntax_extension`.
 113     /// It builds for you a `NormalTT` that calls `expander`,
 114     /// and also takes care of interning the macro's name.
 115     pub fn register_macro(&mut self, name: &str, expander: MacroExpanderFn) {
 116         self.register_syntax_extension(token::intern(name),
 117                                        NormalTT(Box::new(expander), None, false));
 118     }
 119
 120     /// Register a compiler lint pass.
 121     pub fn register_lint_pass(&mut self, lint_pass: LintPassObject) {
 122         self.lint_passes.push(lint_pass);
 123     }
 124
 125     /// Register a lint group.
 126     pub fn register_lint_group(&mut self, name: &'static str, to: Vec<&'static Lint>) {
 127         self.lint_groups.insert(name, to.into_iter().map(|x| LintId::of(x)).collect());
 128     }
 129
 130     /// Register an LLVM pass.
 131     ///
 132     /// Registration with LLVM itself is handled through static C++ objects with
 133     /// constructors. This method simply adds a name to the list of passes to
 134     /// execute.
 135     pub fn register_llvm_pass(&mut self, name: &str) {
 136         self.llvm_passes.push(name.to_owned());
 137     }
 138
 139
 140     /// Register an attribute with an attribute type.
 141     ///
 142     /// Registered attributes will bypass the `custom_attribute` feature gate.
 143     /// `Whitelisted` attributes will additionally not trigger the `unused_attribute`
 144     /// lint. `CrateLevel` attributes will not be allowed on anything other than a crate.
 145     pub fn register_attribute(&mut self, name: String, ty: AttributeType) {
 146         self.attributes.push((name, ty));
 147     }
 148 }