rust/src/librustc_privacy/lib.rs

1578 lines
65 KiB
Rust

// Copyright 2012-2014 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.
#![crate_name = "rustc_privacy"]
#![unstable]
#![staged_api]
#![crate_type = "dylib"]
#![crate_type = "rlib"]
#![doc(html_logo_url = "http://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
html_favicon_url = "http://www.rust-lang.org/favicon.ico",
html_root_url = "http://doc.rust-lang.org/nightly/")]
#![feature(rustc_diagnostic_macros)]
#![allow(unknown_features)] #![feature(int_uint)]
#![allow(unstable)]
#[macro_use] extern crate log;
#[macro_use] extern crate syntax;
extern crate rustc;
use self::PrivacyResult::*;
use self::FieldName::*;
use std::mem::replace;
use rustc::metadata::csearch;
use rustc::middle::def;
use rustc::middle::privacy::ImportUse::*;
use rustc::middle::privacy::LastPrivate::*;
use rustc::middle::privacy::PrivateDep::*;
use rustc::middle::privacy::{ExportedItems, PublicItems, LastPrivateMap};
use rustc::middle::privacy::{ExternalExports};
use rustc::middle::ty::{MethodTypeParam, MethodStatic};
use rustc::middle::ty::{MethodCall, MethodMap, MethodOrigin, MethodParam};
use rustc::middle::ty::{MethodStaticClosure, MethodObject};
use rustc::middle::ty::{MethodTraitObject};
use rustc::middle::ty::{self, Ty};
use rustc::util::nodemap::{NodeMap, NodeSet};
use syntax::{ast, ast_map};
use syntax::ast_util::{is_local, local_def, PostExpansionMethod};
use syntax::codemap::Span;
use syntax::parse::token;
use syntax::visit::{self, Visitor};
type Context<'a, 'tcx> = (&'a MethodMap<'tcx>, &'a def::ExportMap);
/// Result of a checking operation - None => no errors were found. Some => an
/// error and contains the span and message for reporting that error and
/// optionally the same for a note about the error.
type CheckResult = Option<(Span, String, Option<(Span, String)>)>;
////////////////////////////////////////////////////////////////////////////////
/// The parent visitor, used to determine what's the parent of what (node-wise)
////////////////////////////////////////////////////////////////////////////////
struct ParentVisitor {
parents: NodeMap<ast::NodeId>,
curparent: ast::NodeId,
}
impl<'v> Visitor<'v> for ParentVisitor {
fn visit_item(&mut self, item: &ast::Item) {
self.parents.insert(item.id, self.curparent);
let prev = self.curparent;
match item.node {
ast::ItemMod(..) => { self.curparent = item.id; }
// Enum variants are parented to the enum definition itself because
// they inherit privacy
ast::ItemEnum(ref def, _) => {
for variant in def.variants.iter() {
// The parent is considered the enclosing enum because the
// enum will dictate the privacy visibility of this variant
// instead.
self.parents.insert(variant.node.id, item.id);
}
}
// Trait methods are always considered "public", but if the trait is
// private then we need some private item in the chain from the
// method to the root. In this case, if the trait is private, then
// parent all the methods to the trait to indicate that they're
// private.
ast::ItemTrait(_, _, _, ref methods) if item.vis != ast::Public => {
for m in methods.iter() {
match *m {
ast::ProvidedMethod(ref m) => {
self.parents.insert(m.id, item.id);
}
ast::RequiredMethod(ref m) => {
self.parents.insert(m.id, item.id);
}
ast::TypeTraitItem(_) => {}
};
}
}
_ => {}
}
visit::walk_item(self, item);
self.curparent = prev;
}
fn visit_foreign_item(&mut self, a: &ast::ForeignItem) {
self.parents.insert(a.id, self.curparent);
visit::walk_foreign_item(self, a);
}
fn visit_fn(&mut self, a: visit::FnKind<'v>, b: &'v ast::FnDecl,
c: &'v ast::Block, d: Span, id: ast::NodeId) {
// We already took care of some trait methods above, otherwise things
// like impl methods and pub trait methods are parented to the
// containing module, not the containing trait.
if !self.parents.contains_key(&id) {
self.parents.insert(id, self.curparent);
}
visit::walk_fn(self, a, b, c, d);
}
fn visit_struct_def(&mut self, s: &ast::StructDef, _: ast::Ident,
_: &'v ast::Generics, n: ast::NodeId) {
// Struct constructors are parented to their struct definitions because
// they essentially are the struct definitions.
match s.ctor_id {
Some(id) => { self.parents.insert(id, n); }
None => {}
}
// While we have the id of the struct definition, go ahead and parent
// all the fields.
for field in s.fields.iter() {
self.parents.insert(field.node.id, self.curparent);
}
visit::walk_struct_def(self, s)
}
}
////////////////////////////////////////////////////////////////////////////////
/// The embargo visitor, used to determine the exports of the ast
////////////////////////////////////////////////////////////////////////////////
struct EmbargoVisitor<'a, 'tcx: 'a> {
tcx: &'a ty::ctxt<'tcx>,
export_map: &'a def::ExportMap,
// This flag is an indicator of whether the previous item in the
// hierarchical chain was exported or not. This is the indicator of whether
// children should be exported as well. Note that this can flip from false
// to true if a reexported module is entered (or an action similar).
prev_exported: bool,
// This is a list of all exported items in the AST. An exported item is any
// function/method/item which is usable by external crates. This essentially
// means that the result is "public all the way down", but the "path down"
// may jump across private boundaries through reexport statements.
exported_items: ExportedItems,
// This sets contains all the destination nodes which are publicly
// re-exported. This is *not* a set of all reexported nodes, only a set of
// all nodes which are reexported *and* reachable from external crates. This
// means that the destination of the reexport is exported, and hence the
// destination must also be exported.
reexports: NodeSet,
// These two fields are closely related to one another in that they are only
// used for generation of the 'PublicItems' set, not for privacy checking at
// all
public_items: PublicItems,
prev_public: bool,
}
impl<'a, 'tcx> EmbargoVisitor<'a, 'tcx> {
// There are checks inside of privacy which depend on knowing whether a
// trait should be exported or not. The two current consumers of this are:
//
// 1. Should default methods of a trait be exported?
// 2. Should the methods of an implementation of a trait be exported?
//
// The answer to both of these questions partly rely on whether the trait
// itself is exported or not. If the trait is somehow exported, then the
// answers to both questions must be yes. Right now this question involves
// more analysis than is currently done in rustc, so we conservatively
// answer "yes" so that all traits need to be exported.
fn exported_trait(&self, _id: ast::NodeId) -> bool {
true
}
}
impl<'a, 'tcx, 'v> Visitor<'v> for EmbargoVisitor<'a, 'tcx> {
fn visit_item(&mut self, item: &ast::Item) {
let orig_all_pub = self.prev_public;
self.prev_public = orig_all_pub && item.vis == ast::Public;
if self.prev_public {
self.public_items.insert(item.id);
}
let orig_all_exported = self.prev_exported;
match item.node {
// impls/extern blocks do not break the "public chain" because they
// cannot have visibility qualifiers on them anyway
ast::ItemImpl(..) | ast::ItemForeignMod(..) => {}
// Traits are a little special in that even if they themselves are
// not public they may still be exported.
ast::ItemTrait(..) => {
self.prev_exported = self.exported_trait(item.id);
}
// Private by default, hence we only retain the "public chain" if
// `pub` is explicitly listed.
_ => {
self.prev_exported =
(orig_all_exported && item.vis == ast::Public) ||
self.reexports.contains(&item.id);
}
}
let public_first = self.prev_exported &&
self.exported_items.insert(item.id);
match item.node {
// Enum variants inherit from their parent, so if the enum is
// public all variants are public unless they're explicitly priv
ast::ItemEnum(ref def, _) if public_first => {
for variant in def.variants.iter() {
self.exported_items.insert(variant.node.id);
}
}
// Implementations are a little tricky to determine what's exported
// out of them. Here's a few cases which are currently defined:
//
// * Impls for private types do not need to export their methods
// (either public or private methods)
//
// * Impls for public types only have public methods exported
//
// * Public trait impls for public types must have all methods
// exported.
//
// * Private trait impls for public types can be ignored
//
// * Public trait impls for private types have their methods
// exported. I'm not entirely certain that this is the correct
// thing to do, but I have seen use cases of where this will cause
// undefined symbols at linkage time if this case is not handled.
//
// * Private trait impls for private types can be completely ignored
ast::ItemImpl(_, _, _, _, ref ty, ref impl_items) => {
let public_ty = match ty.node {
ast::TyPath(_, id) => {
match self.tcx.def_map.borrow()[id].clone() {
def::DefPrimTy(..) => true,
def => {
let did = def.def_id();
!is_local(did) ||
self.exported_items.contains(&did.node)
}
}
}
_ => true,
};
let tr = ty::impl_trait_ref(self.tcx, local_def(item.id));
let public_trait = tr.clone().map_or(false, |tr| {
!is_local(tr.def_id) ||
self.exported_items.contains(&tr.def_id.node)
});
if public_ty || public_trait {
for impl_item in impl_items.iter() {
match *impl_item {
ast::MethodImplItem(ref method) => {
let meth_public =
match method.pe_explicit_self().node {
ast::SelfStatic => public_ty,
_ => true,
} && method.pe_vis() == ast::Public;
if meth_public || tr.is_some() {
self.exported_items.insert(method.id);
}
}
ast::TypeImplItem(_) => {}
}
}
}
}
// Default methods on traits are all public so long as the trait
// is public
ast::ItemTrait(_, _, _, ref methods) if public_first => {
for method in methods.iter() {
match *method {
ast::ProvidedMethod(ref m) => {
debug!("provided {}", m.id);
self.exported_items.insert(m.id);
}
ast::RequiredMethod(ref m) => {
debug!("required {}", m.id);
self.exported_items.insert(m.id);
}
ast::TypeTraitItem(ref t) => {
debug!("typedef {}", t.ty_param.id);
self.exported_items.insert(t.ty_param.id);
}
}
}
}
// Struct constructors are public if the struct is all public.
ast::ItemStruct(ref def, _) if public_first => {
match def.ctor_id {
Some(id) => { self.exported_items.insert(id); }
None => {}
}
}
ast::ItemTy(ref ty, _) if public_first => {
if let ast::TyPath(_, id) = ty.node {
match self.tcx.def_map.borrow()[id].clone() {
def::DefPrimTy(..) | def::DefTyParam(..) => {},
def => {
let did = def.def_id();
if is_local(did) {
self.exported_items.insert(did.node);
}
}
}
}
}
_ => {}
}
visit::walk_item(self, item);
self.prev_exported = orig_all_exported;
self.prev_public = orig_all_pub;
}
fn visit_foreign_item(&mut self, a: &ast::ForeignItem) {
if (self.prev_exported && a.vis == ast::Public) || self.reexports.contains(&a.id) {
self.exported_items.insert(a.id);
}
}
fn visit_mod(&mut self, m: &ast::Mod, _sp: Span, id: ast::NodeId) {
// This code is here instead of in visit_item so that the
// crate module gets processed as well.
if self.prev_exported {
assert!(self.export_map.contains_key(&id), "wut {}", id);
for export in self.export_map[id].iter() {
if is_local(export.def_id) {
self.reexports.insert(export.def_id.node);
}
}
}
visit::walk_mod(self, m)
}
}
////////////////////////////////////////////////////////////////////////////////
/// The privacy visitor, where privacy checks take place (violations reported)
////////////////////////////////////////////////////////////////////////////////
struct PrivacyVisitor<'a, 'tcx: 'a> {
tcx: &'a ty::ctxt<'tcx>,
curitem: ast::NodeId,
in_foreign: bool,
parents: NodeMap<ast::NodeId>,
external_exports: ExternalExports,
last_private_map: LastPrivateMap,
}
enum PrivacyResult {
Allowable,
ExternallyDenied,
DisallowedBy(ast::NodeId),
}
enum FieldName {
UnnamedField(uint), // index
// FIXME #6993: change type (and name) from Ident to Name
NamedField(ast::Ident),
}
impl<'a, 'tcx> PrivacyVisitor<'a, 'tcx> {
// used when debugging
fn nodestr(&self, id: ast::NodeId) -> String {
self.tcx.map.node_to_string(id).to_string()
}
// Determines whether the given definition is public from the point of view
// of the current item.
fn def_privacy(&self, did: ast::DefId) -> PrivacyResult {
if !is_local(did) {
if self.external_exports.contains(&did) {
debug!("privacy - {:?} was externally exported", did);
return Allowable;
}
debug!("privacy - is {:?} a public method", did);
return match self.tcx.impl_or_trait_items.borrow().get(&did) {
Some(&ty::MethodTraitItem(ref meth)) => {
debug!("privacy - well at least it's a method: {:?}",
*meth);
match meth.container {
ty::TraitContainer(id) => {
debug!("privacy - recursing on trait {:?}", id);
self.def_privacy(id)
}
ty::ImplContainer(id) => {
match ty::impl_trait_ref(self.tcx, id) {
Some(t) => {
debug!("privacy - impl of trait {:?}", id);
self.def_privacy(t.def_id)
}
None => {
debug!("privacy - found a method {:?}",
meth.vis);
if meth.vis == ast::Public {
Allowable
} else {
ExternallyDenied
}
}
}
}
}
}
Some(&ty::TypeTraitItem(ref typedef)) => {
match typedef.container {
ty::TraitContainer(id) => {
debug!("privacy - recursing on trait {:?}", id);
self.def_privacy(id)
}
ty::ImplContainer(id) => {
match ty::impl_trait_ref(self.tcx, id) {
Some(t) => {
debug!("privacy - impl of trait {:?}", id);
self.def_privacy(t.def_id)
}
None => {
debug!("privacy - found a typedef {:?}",
typedef.vis);
if typedef.vis == ast::Public {
Allowable
} else {
ExternallyDenied
}
}
}
}
}
}
None => {
debug!("privacy - nope, not even a method");
ExternallyDenied
}
};
}
debug!("privacy - local {} not public all the way down",
self.tcx.map.node_to_string(did.node));
// return quickly for things in the same module
if self.parents.get(&did.node) == self.parents.get(&self.curitem) {
debug!("privacy - same parent, we're done here");
return Allowable;
}
// We now know that there is at least one private member between the
// destination and the root.
let mut closest_private_id = did.node;
loop {
debug!("privacy - examining {}", self.nodestr(closest_private_id));
let vis = match self.tcx.map.find(closest_private_id) {
// If this item is a method, then we know for sure that it's an
// actual method and not a static method. The reason for this is
// that these cases are only hit in the ExprMethodCall
// expression, and ExprCall will have its path checked later
// (the path of the trait/impl) if it's a static method.
//
// With this information, then we can completely ignore all
// trait methods. The privacy violation would be if the trait
// couldn't get imported, not if the method couldn't be used
// (all trait methods are public).
//
// However, if this is an impl method, then we dictate this
// decision solely based on the privacy of the method
// invocation.
// FIXME(#10573) is this the right behavior? Why not consider
// where the method was defined?
Some(ast_map::NodeImplItem(ii)) => {
match *ii {
ast::MethodImplItem(ref m) => {
let imp = self.tcx.map
.get_parent_did(closest_private_id);
match ty::impl_trait_ref(self.tcx, imp) {
Some(..) => return Allowable,
_ if m.pe_vis() == ast::Public => {
return Allowable
}
_ => m.pe_vis()
}
}
ast::TypeImplItem(_) => return Allowable,
}
}
Some(ast_map::NodeTraitItem(_)) => {
return Allowable;
}
// This is not a method call, extract the visibility as one
// would normally look at it
Some(ast_map::NodeItem(it)) => it.vis,
Some(ast_map::NodeForeignItem(_)) => {
self.tcx.map.get_foreign_vis(closest_private_id)
}
Some(ast_map::NodeVariant(..)) => {
ast::Public // need to move up a level (to the enum)
}
_ => ast::Public,
};
if vis != ast::Public { break }
// if we've reached the root, then everything was allowable and this
// access is public.
if closest_private_id == ast::CRATE_NODE_ID { return Allowable }
closest_private_id = self.parents[closest_private_id];
// If we reached the top, then we were public all the way down and
// we can allow this access.
if closest_private_id == ast::DUMMY_NODE_ID { return Allowable }
}
debug!("privacy - closest priv {}", self.nodestr(closest_private_id));
if self.private_accessible(closest_private_id) {
Allowable
} else {
DisallowedBy(closest_private_id)
}
}
/// For a local private node in the AST, this function will determine
/// whether the node is accessible by the current module that iteration is
/// inside.
fn private_accessible(&self, id: ast::NodeId) -> bool {
let parent = self.parents[id];
debug!("privacy - accessible parent {}", self.nodestr(parent));
// After finding `did`'s closest private member, we roll ourselves back
// to see if this private member's parent is anywhere in our ancestry.
// By the privacy rules, we can access all of our ancestor's private
// members, so that's why we test the parent, and not the did itself.
let mut cur = self.curitem;
loop {
debug!("privacy - questioning {}, {}", self.nodestr(cur), cur);
match cur {
// If the relevant parent is in our history, then we're allowed
// to look inside any of our ancestor's immediate private items,
// so this access is valid.
x if x == parent => return true,
// If we've reached the root, then we couldn't access this item
// in the first place
ast::DUMMY_NODE_ID => return false,
// Keep going up
_ => {}
}
cur = self.parents[cur];
}
}
fn report_error(&self, result: CheckResult) -> bool {
match result {
None => true,
Some((span, msg, note)) => {
self.tcx.sess.span_err(span, &msg[]);
match note {
Some((span, msg)) => {
self.tcx.sess.span_note(span, &msg[])
}
None => {},
}
false
},
}
}
/// Guarantee that a particular definition is public. Returns a CheckResult
/// which contains any errors found. These can be reported using `report_error`.
/// If the result is `None`, no errors were found.
fn ensure_public(&self, span: Span, to_check: ast::DefId,
source_did: Option<ast::DefId>, msg: &str) -> CheckResult {
let id = match self.def_privacy(to_check) {
ExternallyDenied => {
return Some((span, format!("{} is private", msg), None))
}
Allowable => return None,
DisallowedBy(id) => id,
};
// If we're disallowed by a particular id, then we attempt to give a
// nice error message to say why it was disallowed. It was either
// because the item itself is private or because its parent is private
// and its parent isn't in our ancestry.
let (err_span, err_msg) = if id == source_did.unwrap_or(to_check).node {
return Some((span, format!("{} is private", msg), None));
} else {
(span, format!("{} is inaccessible", msg))
};
let item = match self.tcx.map.find(id) {
Some(ast_map::NodeItem(item)) => {
match item.node {
// If an impl disallowed this item, then this is resolve's
// way of saying that a struct/enum's static method was
// invoked, and the struct/enum itself is private. Crawl
// back up the chains to find the relevant struct/enum that
// was private.
ast::ItemImpl(_, _, _, _, ref ty, _) => {
let id = match ty.node {
ast::TyPath(_, id) => id,
_ => return Some((err_span, err_msg, None)),
};
let def = self.tcx.def_map.borrow()[id].clone();
let did = def.def_id();
assert!(is_local(did));
match self.tcx.map.get(did.node) {
ast_map::NodeItem(item) => item,
_ => self.tcx.sess.span_bug(item.span,
"path is not an item")
}
}
_ => item
}
}
Some(..) | None => return Some((err_span, err_msg, None)),
};
let desc = match item.node {
ast::ItemMod(..) => "module",
ast::ItemTrait(..) => "trait",
ast::ItemStruct(..) => "struct",
ast::ItemEnum(..) => "enum",
_ => return Some((err_span, err_msg, None))
};
let msg = format!("{} `{}` is private", desc,
token::get_ident(item.ident));
Some((err_span, err_msg, Some((span, msg))))
}
// Checks that a field is in scope.
fn check_field(&mut self,
span: Span,
id: ast::DefId,
name: FieldName) {
let fields = ty::lookup_struct_fields(self.tcx, id);
let field = match name {
NamedField(ident) => {
debug!("privacy - check named field {} in struct {:?}", ident.name, id);
fields.iter().find(|f| f.name == ident.name).unwrap()
}
UnnamedField(idx) => &fields[idx]
};
if field.vis == ast::Public ||
(is_local(field.id) && self.private_accessible(field.id.node)) {
return
}
let struct_type = ty::lookup_item_type(self.tcx, id).ty;
let struct_desc = match struct_type.sty {
ty::ty_struct(_, _) =>
format!("struct `{}`", ty::item_path_str(self.tcx, id)),
// struct variant fields have inherited visibility
ty::ty_enum(..) => return,
_ => self.tcx.sess.span_bug(span, "can't find struct for field")
};
let msg = match name {
NamedField(name) => format!("field `{}` of {} is private",
token::get_ident(name), struct_desc),
UnnamedField(idx) => format!("field #{} of {} is private",
idx + 1, struct_desc),
};
self.tcx.sess.span_err(span, &msg[]);
}
// Given the ID of a method, checks to ensure it's in scope.
fn check_static_method(&mut self,
span: Span,
method_id: ast::DefId,
name: ast::Ident) {
// If the method is a default method, we need to use the def_id of
// the default implementation.
let method_id = match ty::impl_or_trait_item(self.tcx, method_id) {
ty::MethodTraitItem(method_type) => {
method_type.provided_source.unwrap_or(method_id)
}
ty::TypeTraitItem(_) => method_id,
};
let string = token::get_ident(name);
self.report_error(self.ensure_public(span,
method_id,
None,
&format!("method `{}`",
string)[]));
}
// Checks that a path is in scope.
fn check_path(&mut self, span: Span, path_id: ast::NodeId, path: &ast::Path) {
debug!("privacy - path {}", self.nodestr(path_id));
let orig_def = self.tcx.def_map.borrow()[path_id].clone();
let ck = |&: tyname: &str| {
let ck_public = |&: def: ast::DefId| {
debug!("privacy - ck_public {:?}", def);
let name = token::get_ident(path.segments.last().unwrap().identifier);
let origdid = orig_def.def_id();
self.ensure_public(span,
def,
Some(origdid),
&format!("{} `{}`", tyname, name)[])
};
match self.last_private_map[path_id] {
LastMod(AllPublic) => {},
LastMod(DependsOn(def)) => {
self.report_error(ck_public(def));
},
LastImport { value_priv,
value_used: check_value,
type_priv,
type_used: check_type } => {
// This dance with found_error is because we don't want to
// report a privacy error twice for the same directive.
let found_error = match (type_priv, check_type) {
(Some(DependsOn(def)), Used) => {
!self.report_error(ck_public(def))
},
_ => false,
};
if !found_error {
match (value_priv, check_value) {
(Some(DependsOn(def)), Used) => {
self.report_error(ck_public(def));
},
_ => {},
}
}
// If an import is not used in either namespace, we still
// want to check that it could be legal. Therefore we check
// in both namespaces and only report an error if both would
// be illegal. We only report one error, even if it is
// illegal to import from both namespaces.
match (value_priv, check_value, type_priv, check_type) {
(Some(p), Unused, None, _) |
(None, _, Some(p), Unused) => {
let p = match p {
AllPublic => None,
DependsOn(def) => ck_public(def),
};
if p.is_some() {
self.report_error(p);
}
},
(Some(v), Unused, Some(t), Unused) => {
let v = match v {
AllPublic => None,
DependsOn(def) => ck_public(def),
};
let t = match t {
AllPublic => None,
DependsOn(def) => ck_public(def),
};
if let (Some(_), Some(t)) = (v, t) {
self.report_error(Some(t));
}
},
_ => {},
}
},
}
};
// FIXME(#12334) Imports can refer to definitions in both the type and
// value namespaces. The privacy information is aware of this, but the
// def map is not. Therefore the names we work out below will not always
// be accurate and we can get slightly wonky error messages (but type
// checking is always correct).
match self.tcx.def_map.borrow()[path_id].clone() {
def::DefStaticMethod(..) => ck("static method"),
def::DefFn(..) => ck("function"),
def::DefStatic(..) => ck("static"),
def::DefConst(..) => ck("const"),
def::DefVariant(..) => ck("variant"),
def::DefTy(_, false) => ck("type"),
def::DefTy(_, true) => ck("enum"),
def::DefTrait(..) => ck("trait"),
def::DefStruct(..) => ck("struct"),
def::DefMethod(_, Some(..), _) => ck("trait method"),
def::DefMethod(..) => ck("method"),
def::DefMod(..) => ck("module"),
_ => {}
}
}
// Checks that a method is in scope.
fn check_method(&mut self, span: Span, origin: &MethodOrigin,
ident: ast::Ident) {
match *origin {
MethodStatic(method_id) => {
self.check_static_method(span, method_id, ident)
}
MethodStaticClosure(_) => {}
// Trait methods are always all public. The only controlling factor
// is whether the trait itself is accessible or not.
MethodTypeParam(MethodParam { ref trait_ref, .. }) |
MethodTraitObject(MethodObject { ref trait_ref, .. }) => {
self.report_error(self.ensure_public(span, trait_ref.def_id,
None, "source trait"));
}
}
}
}
impl<'a, 'tcx, 'v> Visitor<'v> for PrivacyVisitor<'a, 'tcx> {
fn visit_item(&mut self, item: &ast::Item) {
match item.node {
ast::ItemUse(ref vpath) => {
match vpath.node {
ast::ViewPathSimple(..) | ast::ViewPathGlob(..) => {}
ast::ViewPathList(ref prefix, ref list) => {
for pid in list.iter() {
match pid.node {
ast::PathListIdent { id, name } => {
debug!("privacy - ident item {}", id);
let seg = ast::PathSegment {
identifier: name,
parameters: ast::PathParameters::none(),
};
let segs = vec![seg];
let path = ast::Path {
global: false,
span: pid.span,
segments: segs,
};
self.check_path(pid.span, id, &path);
}
ast::PathListMod { id } => {
debug!("privacy - mod item {}", id);
self.check_path(pid.span, id, prefix);
}
}
}
}
}
}
_ => {}
}
let orig_curitem = replace(&mut self.curitem, item.id);
visit::walk_item(self, item);
self.curitem = orig_curitem;
}
fn visit_expr(&mut self, expr: &ast::Expr) {
match expr.node {
ast::ExprField(ref base, ident) => {
if let ty::ty_struct(id, _) = ty::expr_ty_adjusted(self.tcx, &**base).sty {
self.check_field(expr.span, id, NamedField(ident.node));
}
}
ast::ExprTupField(ref base, idx) => {
if let ty::ty_struct(id, _) = ty::expr_ty_adjusted(self.tcx, &**base).sty {
self.check_field(expr.span, id, UnnamedField(idx.node));
}
}
ast::ExprMethodCall(ident, _, _) => {
let method_call = MethodCall::expr(expr.id);
match self.tcx.method_map.borrow().get(&method_call) {
None => {
self.tcx.sess.span_bug(expr.span,
"method call not in \
method map");
}
Some(method) => {
debug!("(privacy checking) checking impl method");
self.check_method(expr.span, &method.origin, ident.node);
}
}
}
ast::ExprStruct(_, ref fields, _) => {
match ty::expr_ty(self.tcx, expr).sty {
ty::ty_struct(id, _) => {
for field in (*fields).iter() {
self.check_field(expr.span, id,
NamedField(field.ident.node));
}
}
ty::ty_enum(_, _) => {
match self.tcx.def_map.borrow()[expr.id].clone() {
def::DefVariant(_, variant_id, _) => {
for field in fields.iter() {
self.check_field(expr.span, variant_id,
NamedField(field.ident.node));
}
}
_ => self.tcx.sess.span_bug(expr.span,
"resolve didn't \
map enum struct \
constructor to a \
variant def"),
}
}
_ => self.tcx.sess.span_bug(expr.span, "struct expr \
didn't have \
struct type?!"),
}
}
ast::ExprPath(_) | ast::ExprQPath(_) => {
let guard = |&: did: ast::DefId| {
let fields = ty::lookup_struct_fields(self.tcx, did);
let any_priv = fields.iter().any(|f| {
f.vis != ast::Public && (
!is_local(f.id) ||
!self.private_accessible(f.id.node))
});
if any_priv {
self.tcx.sess.span_err(expr.span,
"cannot invoke tuple struct constructor \
with private fields");
}
};
match self.tcx.def_map.borrow().get(&expr.id) {
Some(&def::DefStruct(did)) => {
guard(if is_local(did) {
local_def(self.tcx.map.get_parent(did.node))
} else {
// "tuple structs" with zero fields (such as
// `pub struct Foo;`) don't have a ctor_id, hence
// the unwrap_or to the same struct id.
let maybe_did =
csearch::get_tuple_struct_definition_if_ctor(
&self.tcx.sess.cstore, did);
maybe_did.unwrap_or(did)
})
}
_ => {}
}
}
_ => {}
}
visit::walk_expr(self, expr);
}
fn visit_pat(&mut self, pattern: &ast::Pat) {
// Foreign functions do not have their patterns mapped in the def_map,
// and there's nothing really relevant there anyway, so don't bother
// checking privacy. If you can name the type then you can pass it to an
// external C function anyway.
if self.in_foreign { return }
match pattern.node {
ast::PatStruct(_, ref fields, _) => {
match ty::pat_ty(self.tcx, pattern).sty {
ty::ty_struct(id, _) => {
for field in fields.iter() {
self.check_field(pattern.span, id,
NamedField(field.node.ident));
}
}
ty::ty_enum(_, _) => {
match self.tcx.def_map.borrow().get(&pattern.id) {
Some(&def::DefVariant(_, variant_id, _)) => {
for field in fields.iter() {
self.check_field(pattern.span, variant_id,
NamedField(field.node.ident));
}
}
_ => self.tcx.sess.span_bug(pattern.span,
"resolve didn't \
map enum struct \
pattern to a \
variant def"),
}
}
_ => self.tcx.sess.span_bug(pattern.span,
"struct pattern didn't have \
struct type?!"),
}
}
// Patterns which bind no fields are allowable (the path is check
// elsewhere).
ast::PatEnum(_, Some(ref fields)) => {
match ty::pat_ty(self.tcx, pattern).sty {
ty::ty_struct(id, _) => {
for (i, field) in fields.iter().enumerate() {
if let ast::PatWild(..) = field.node {
continue
}
self.check_field(field.span, id, UnnamedField(i));
}
}
ty::ty_enum(..) => {
// enum fields have no privacy at this time
}
_ => {}
}
}
_ => {}
}
visit::walk_pat(self, pattern);
}
fn visit_foreign_item(&mut self, fi: &ast::ForeignItem) {
self.in_foreign = true;
visit::walk_foreign_item(self, fi);
self.in_foreign = false;
}
fn visit_path(&mut self, path: &ast::Path, id: ast::NodeId) {
self.check_path(path.span, id, path);
visit::walk_path(self, path);
}
}
////////////////////////////////////////////////////////////////////////////////
/// The privacy sanity check visitor, ensures unnecessary visibility isn't here
////////////////////////////////////////////////////////////////////////////////
struct SanePrivacyVisitor<'a, 'tcx: 'a> {
tcx: &'a ty::ctxt<'tcx>,
in_fn: bool,
}
impl<'a, 'tcx, 'v> Visitor<'v> for SanePrivacyVisitor<'a, 'tcx> {
fn visit_item(&mut self, item: &ast::Item) {
if self.in_fn {
self.check_all_inherited(item);
} else {
self.check_sane_privacy(item);
}
let in_fn = self.in_fn;
let orig_in_fn = replace(&mut self.in_fn, match item.node {
ast::ItemMod(..) => false, // modules turn privacy back on
_ => in_fn, // otherwise we inherit
});
visit::walk_item(self, item);
self.in_fn = orig_in_fn;
}
fn visit_fn(&mut self, fk: visit::FnKind<'v>, fd: &'v ast::FnDecl,
b: &'v ast::Block, s: Span, _: ast::NodeId) {
// This catches both functions and methods
let orig_in_fn = replace(&mut self.in_fn, true);
visit::walk_fn(self, fk, fd, b, s);
self.in_fn = orig_in_fn;
}
}
impl<'a, 'tcx> SanePrivacyVisitor<'a, 'tcx> {
/// Validates all of the visibility qualifiers placed on the item given. This
/// ensures that there are no extraneous qualifiers that don't actually do
/// anything. In theory these qualifiers wouldn't parse, but that may happen
/// later on down the road...
fn check_sane_privacy(&self, item: &ast::Item) {
let tcx = self.tcx;
let check_inherited = |&: sp: Span, vis: ast::Visibility, note: &str| {
if vis != ast::Inherited {
tcx.sess.span_err(sp, "unnecessary visibility qualifier");
if note.len() > 0 {
tcx.sess.span_note(sp, note);
}
}
};
match item.node {
// implementations of traits don't need visibility qualifiers because
// that's controlled by having the trait in scope.
ast::ItemImpl(_, _, _, Some(..), _, ref impl_items) => {
check_inherited(item.span, item.vis,
"visibility qualifiers have no effect on trait \
impls");
for impl_item in impl_items.iter() {
match *impl_item {
ast::MethodImplItem(ref m) => {
check_inherited(m.span, m.pe_vis(), "");
}
ast::TypeImplItem(_) => {}
}
}
}
ast::ItemImpl(..) => {
check_inherited(item.span, item.vis,
"place qualifiers on individual methods instead");
}
ast::ItemForeignMod(..) => {
check_inherited(item.span, item.vis,
"place qualifiers on individual functions \
instead");
}
ast::ItemEnum(ref def, _) => {
for v in def.variants.iter() {
match v.node.vis {
ast::Public => {
if item.vis == ast::Public {
tcx.sess.span_err(v.span, "unnecessary `pub` \
visibility");
}
}
ast::Inherited => {}
}
}
}
ast::ItemTrait(_, _, _, ref methods) => {
for m in methods.iter() {
match *m {
ast::ProvidedMethod(ref m) => {
check_inherited(m.span, m.pe_vis(),
"unnecessary visibility");
}
ast::RequiredMethod(ref m) => {
check_inherited(m.span, m.vis,
"unnecessary visibility");
}
ast::TypeTraitItem(_) => {}
}
}
}
ast::ItemConst(..) | ast::ItemStatic(..) | ast::ItemStruct(..) |
ast::ItemFn(..) | ast::ItemMod(..) | ast::ItemTy(..) |
ast::ItemExternCrate(_) | ast::ItemUse(_) | ast::ItemMac(..) => {}
}
}
/// When inside of something like a function or a method, visibility has no
/// control over anything so this forbids any mention of any visibility
fn check_all_inherited(&self, item: &ast::Item) {
let tcx = self.tcx;
fn check_inherited(tcx: &ty::ctxt, sp: Span, vis: ast::Visibility) {
if vis != ast::Inherited {
tcx.sess.span_err(sp, "visibility has no effect inside functions");
}
}
let check_struct = |&: def: &ast::StructDef| {
for f in def.fields.iter() {
match f.node.kind {
ast::NamedField(_, p) => check_inherited(tcx, f.span, p),
ast::UnnamedField(..) => {}
}
}
};
check_inherited(tcx, item.span, item.vis);
match item.node {
ast::ItemImpl(_, _, _, _, _, ref impl_items) => {
for impl_item in impl_items.iter() {
match *impl_item {
ast::MethodImplItem(ref m) => {
check_inherited(tcx, m.span, m.pe_vis());
}
ast::TypeImplItem(_) => {}
}
}
}
ast::ItemForeignMod(ref fm) => {
for i in fm.items.iter() {
check_inherited(tcx, i.span, i.vis);
}
}
ast::ItemEnum(ref def, _) => {
for v in def.variants.iter() {
check_inherited(tcx, v.span, v.node.vis);
}
}
ast::ItemStruct(ref def, _) => check_struct(&**def),
ast::ItemTrait(_, _, _, ref methods) => {
for m in methods.iter() {
match *m {
ast::RequiredMethod(..) => {}
ast::ProvidedMethod(ref m) => check_inherited(tcx, m.span,
m.pe_vis()),
ast::TypeTraitItem(_) => {}
}
}
}
ast::ItemExternCrate(_) | ast::ItemUse(_) |
ast::ItemStatic(..) | ast::ItemConst(..) |
ast::ItemFn(..) | ast::ItemMod(..) | ast::ItemTy(..) |
ast::ItemMac(..) => {}
}
}
}
struct VisiblePrivateTypesVisitor<'a, 'tcx: 'a> {
tcx: &'a ty::ctxt<'tcx>,
exported_items: &'a ExportedItems,
public_items: &'a PublicItems,
in_variant: bool,
}
struct CheckTypeForPrivatenessVisitor<'a, 'b: 'a, 'tcx: 'b> {
inner: &'a VisiblePrivateTypesVisitor<'b, 'tcx>,
/// whether the type refers to private types.
contains_private: bool,
/// whether we've recurred at all (i.e. if we're pointing at the
/// first type on which visit_ty was called).
at_outer_type: bool,
// whether that first type is a public path.
outer_type_is_public_path: bool,
}
impl<'a, 'tcx> VisiblePrivateTypesVisitor<'a, 'tcx> {
fn path_is_private_type(&self, path_id: ast::NodeId) -> bool {
let did = match self.tcx.def_map.borrow().get(&path_id).cloned() {
// `int` etc. (None doesn't seem to occur.)
None | Some(def::DefPrimTy(..)) => return false,
Some(def) => def.def_id()
};
// A path can only be private if:
// it's in this crate...
if !is_local(did) {
return false
}
// .. and it corresponds to a private type in the AST (this returns
// None for type parameters)
match self.tcx.map.find(did.node) {
Some(ast_map::NodeItem(ref item)) => item.vis != ast::Public,
Some(_) | None => false,
}
}
fn trait_is_public(&self, trait_id: ast::NodeId) -> bool {
// FIXME: this would preferably be using `exported_items`, but all
// traits are exported currently (see `EmbargoVisitor.exported_trait`)
self.public_items.contains(&trait_id)
}
fn check_ty_param_bound(&self,
ty_param_bound: &ast::TyParamBound) {
if let ast::TraitTyParamBound(ref trait_ref, _) = *ty_param_bound {
if !self.tcx.sess.features.borrow().visible_private_types &&
self.path_is_private_type(trait_ref.trait_ref.ref_id) {
let span = trait_ref.trait_ref.path.span;
self.tcx.sess.span_err(span,
"private trait in exported type \
parameter bound");
}
}
}
}
impl<'a, 'b, 'tcx, 'v> Visitor<'v> for CheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
fn visit_ty(&mut self, ty: &ast::Ty) {
if let ast::TyPath(_, path_id) = ty.node {
if self.inner.path_is_private_type(path_id) {
self.contains_private = true;
// found what we're looking for so let's stop
// working.
return
} else if self.at_outer_type {
self.outer_type_is_public_path = true;
}
}
self.at_outer_type = false;
visit::walk_ty(self, ty)
}
// don't want to recurse into [, .. expr]
fn visit_expr(&mut self, _: &ast::Expr) {}
}
impl<'a, 'tcx, 'v> Visitor<'v> for VisiblePrivateTypesVisitor<'a, 'tcx> {
fn visit_item(&mut self, item: &ast::Item) {
match item.node {
// contents of a private mod can be reexported, so we need
// to check internals.
ast::ItemMod(_) => {}
// An `extern {}` doesn't introduce a new privacy
// namespace (the contents have their own privacies).
ast::ItemForeignMod(_) => {}
ast::ItemTrait(_, _, ref bounds, _) => {
if !self.trait_is_public(item.id) {
return
}
for bound in bounds.iter() {
self.check_ty_param_bound(bound)
}
}
// impls need some special handling to try to offer useful
// error messages without (too many) false positives
// (i.e. we could just return here to not check them at
// all, or some worse estimation of whether an impl is
// publicly visible.
ast::ItemImpl(_, _, ref g, ref trait_ref, ref self_, ref impl_items) => {
// `impl [... for] Private` is never visible.
let self_contains_private;
// impl [... for] Public<...>, but not `impl [... for]
// ~[Public]` or `(Public,)` etc.
let self_is_public_path;
// check the properties of the Self type:
{
let mut visitor = CheckTypeForPrivatenessVisitor {
inner: self,
contains_private: false,
at_outer_type: true,
outer_type_is_public_path: false,
};
visitor.visit_ty(&**self_);
self_contains_private = visitor.contains_private;
self_is_public_path = visitor.outer_type_is_public_path;
}
// miscellaneous info about the impl
// `true` iff this is `impl Private for ...`.
let not_private_trait =
trait_ref.as_ref().map_or(true, // no trait counts as public trait
|tr| {
let did = ty::trait_ref_to_def_id(self.tcx, tr);
!is_local(did) || self.trait_is_public(did.node)
});
// `true` iff this is a trait impl or at least one method is public.
//
// `impl Public { $( fn ...() {} )* }` is not visible.
//
// This is required over just using the methods' privacy
// directly because we might have `impl<T: Foo<Private>> ...`,
// and we shouldn't warn about the generics if all the methods
// are private (because `T` won't be visible externally).
let trait_or_some_public_method =
trait_ref.is_some() ||
impl_items.iter()
.any(|impl_item| {
match *impl_item {
ast::MethodImplItem(ref m) => {
self.exported_items.contains(&m.id)
}
ast::TypeImplItem(_) => false,
}
});
if !self_contains_private &&
not_private_trait &&
trait_or_some_public_method {
visit::walk_generics(self, g);
match *trait_ref {
None => {
for impl_item in impl_items.iter() {
match *impl_item {
ast::MethodImplItem(ref method) => {
visit::walk_method_helper(self, &**method)
}
ast::TypeImplItem(_) => {}
}
}
}
Some(ref tr) => {
// Any private types in a trait impl fall into two
// categories.
// 1. mentioned in the trait definition
// 2. mentioned in the type params/generics
//
// Those in 1. can only occur if the trait is in
// this crate and will've been warned about on the
// trait definition (there's no need to warn twice
// so we don't check the methods).
//
// Those in 2. are warned via walk_generics and this
// call here.
self.visit_trait_ref(tr)
}
}
} else if trait_ref.is_none() && self_is_public_path {
// impl Public<Private> { ... }. Any public static
// methods will be visible as `Public::foo`.
let mut found_pub_static = false;
for impl_item in impl_items.iter() {
match *impl_item {
ast::MethodImplItem(ref method) => {
if method.pe_explicit_self().node ==
ast::SelfStatic &&
self.exported_items
.contains(&method.id) {
found_pub_static = true;
visit::walk_method_helper(self, &**method);
}
}
ast::TypeImplItem(_) => {}
}
}
if found_pub_static {
visit::walk_generics(self, g)
}
}
return
}
// `type ... = ...;` can contain private types, because
// we're introducing a new name.
ast::ItemTy(..) => return,
// not at all public, so we don't care
_ if !self.exported_items.contains(&item.id) => return,
_ => {}
}
// we've carefully constructed it so that if we're here, then
// any `visit_ty`'s will be called on things that are in
// public signatures, i.e. things that we're interested in for
// this visitor.
visit::walk_item(self, item);
}
fn visit_generics(&mut self, generics: &ast::Generics) {
for ty_param in generics.ty_params.iter() {
for bound in ty_param.bounds.iter() {
self.check_ty_param_bound(bound)
}
}
for predicate in generics.where_clause.predicates.iter() {
match predicate {
&ast::WherePredicate::BoundPredicate(ref bound_pred) => {
for bound in bound_pred.bounds.iter() {
self.check_ty_param_bound(bound)
}
}
&ast::WherePredicate::RegionPredicate(_) => {}
&ast::WherePredicate::EqPredicate(ref eq_pred) => {
self.visit_ty(&*eq_pred.ty);
}
}
}
}
fn visit_foreign_item(&mut self, item: &ast::ForeignItem) {
if self.exported_items.contains(&item.id) {
visit::walk_foreign_item(self, item)
}
}
fn visit_fn(&mut self, fk: visit::FnKind<'v>, fd: &'v ast::FnDecl,
b: &'v ast::Block, s: Span, id: ast::NodeId) {
// needs special handling for methods.
if self.exported_items.contains(&id) {
visit::walk_fn(self, fk, fd, b, s);
}
}
fn visit_ty(&mut self, t: &ast::Ty) {
if let ast::TyPath(ref p, path_id) = t.node {
if !self.tcx.sess.features.borrow().visible_private_types &&
self.path_is_private_type(path_id) {
self.tcx.sess.span_err(p.span,
"private type in exported type signature");
}
}
visit::walk_ty(self, t)
}
fn visit_variant(&mut self, v: &ast::Variant, g: &ast::Generics) {
if self.exported_items.contains(&v.node.id) {
self.in_variant = true;
visit::walk_variant(self, v, g);
self.in_variant = false;
}
}
fn visit_struct_field(&mut self, s: &ast::StructField) {
match s.node.kind {
ast::NamedField(_, vis) if vis == ast::Public || self.in_variant => {
visit::walk_struct_field(self, s);
}
_ => {}
}
}
// we don't need to introspect into these at all: an
// expression/block context can't possibly contain exported things.
// (Making them no-ops stops us from traversing the whole AST without
// having to be super careful about our `walk_...` calls above.)
fn visit_block(&mut self, _: &ast::Block) {}
fn visit_expr(&mut self, _: &ast::Expr) {}
}
pub fn check_crate(tcx: &ty::ctxt,
export_map: &def::ExportMap,
external_exports: ExternalExports,
last_private_map: LastPrivateMap)
-> (ExportedItems, PublicItems) {
let krate = tcx.map.krate();
// Figure out who everyone's parent is
let mut visitor = ParentVisitor {
parents: NodeMap(),
curparent: ast::DUMMY_NODE_ID,
};
visit::walk_crate(&mut visitor, krate);
// Use the parent map to check the privacy of everything
let mut visitor = PrivacyVisitor {
curitem: ast::DUMMY_NODE_ID,
in_foreign: false,
tcx: tcx,
parents: visitor.parents,
external_exports: external_exports,
last_private_map: last_private_map,
};
visit::walk_crate(&mut visitor, krate);
// Sanity check to make sure that all privacy usage and controls are
// reasonable.
let mut visitor = SanePrivacyVisitor {
in_fn: false,
tcx: tcx,
};
visit::walk_crate(&mut visitor, krate);
tcx.sess.abort_if_errors();
// Build up a set of all exported items in the AST. This is a set of all
// items which are reachable from external crates based on visibility.
let mut visitor = EmbargoVisitor {
tcx: tcx,
exported_items: NodeSet(),
public_items: NodeSet(),
reexports: NodeSet(),
export_map: export_map,
prev_exported: true,
prev_public: true,
};
loop {
let before = visitor.exported_items.len();
visit::walk_crate(&mut visitor, krate);
if before == visitor.exported_items.len() {
break
}
}
let EmbargoVisitor { exported_items, public_items, .. } = visitor;
{
let mut visitor = VisiblePrivateTypesVisitor {
tcx: tcx,
exported_items: &exported_items,
public_items: &public_items,
in_variant: false,
};
visit::walk_crate(&mut visitor, krate);
}
return (exported_items, public_items);
}