diff options
| -rw-r--r-- | src/librustc/middle/lint.rs | 7 | ||||
| -rw-r--r-- | src/librustc/middle/privacy.rs | 255 | ||||
| -rw-r--r-- | src/libsyntax/visit.rs | 13 | ||||
| -rw-r--r-- | src/test/compile-fail/lint-dead-code-1.rs | 1 | ||||
| -rw-r--r-- | src/test/compile-fail/lint-visible-private-types.rs | 129 |
5 files changed, 400 insertions, 5 deletions
diff --git a/src/librustc/middle/lint.rs b/src/librustc/middle/lint.rs index c3e57bd9c60..693f6fb35f4 100644 --- a/src/librustc/middle/lint.rs +++ b/src/librustc/middle/lint.rs @@ -98,6 +98,7 @@ pub enum Lint { UnusedMut, UnnecessaryAllocation, DeadCode, + VisiblePrivateTypes, UnnecessaryTypecast, MissingDoc, @@ -312,6 +313,12 @@ static lint_table: &'static [(&'static str, LintSpec)] = &[ desc: "detect piece of code that will never be used", default: warn }), + ("visible_private_types", + LintSpec { + lint: VisiblePrivateTypes, + desc: "detect use of private types in exported type signatures", + default: warn + }), ("missing_doc", LintSpec { diff --git a/src/librustc/middle/privacy.rs b/src/librustc/middle/privacy.rs index 453160dc001..afe4d001036 100644 --- a/src/librustc/middle/privacy.rs +++ b/src/librustc/middle/privacy.rs @@ -16,6 +16,7 @@ use std::mem::replace; use collections::{HashSet, HashMap}; use metadata::csearch; +use middle::lint; use middle::resolve; use middle::ty; use middle::typeck::{MethodMap, MethodOrigin, MethodParam}; @@ -1169,6 +1170,251 @@ impl SanePrivacyVisitor { } } +struct VisiblePrivateTypesVisitor<'a> { + tcx: ty::ctxt, + exported_items: &'a ExportedItems, + public_items: &'a PublicItems, +} + +struct CheckTypeForPrivatenessVisitor<'a, 'b> { + inner: &'b VisiblePrivateTypesVisitor<'a>, + /// 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> VisiblePrivateTypesVisitor<'a> { + fn path_is_private_type(&self, path_id: ast::NodeId) -> bool { + let did = match self.tcx.def_map.borrow().get().find_copy(&path_id) { + // `int` etc. (None doesn't seem to occur.) + None | Some(ast::DefPrimTy(..)) => return false, + Some(def) => def_id_of_def(def) + }; + // A path can only be private if: + // it's in this crate... + is_local(did) && + // ... it's not exported (obviously) ... + !self.exported_items.contains(&did.node) && + // .. and it corresponds to a type in the AST (this returns None for + // type parameters) + self.tcx.map.find(did.node).is_some() + } + + 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) + } +} + +impl<'a, 'b> Visitor<()> for CheckTypeForPrivatenessVisitor<'a, 'b> { + fn visit_ty(&mut self, ty: &ast::Ty, _: ()) { + match ty.node { + ast::TyPath(_, _, path_id) => { + 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> Visitor<()> for VisiblePrivateTypesVisitor<'a> { + 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(..) if !self.trait_is_public(item.id) => return, + + // 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 + // publically visible. + ast::ItemImpl(ref g, ref trait_ref, self_, ref methods) => { + // `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; + } + + // miscellanous 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() || + methods.iter().any(|m| self.exported_items.contains(&m.id)); + + if !self_contains_private && + not_private_trait && + trait_or_some_public_method { + + visit::walk_generics(self, g, ()); + + match *trait_ref { + None => { + for method in methods.iter() { + visit::walk_method_helper(self, *method, ()) + } + } + 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. + visit::walk_trait_ref_helper(self, 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 method in methods.iter() { + if method.explicit_self.node == ast::SelfStatic && + self.exported_items.contains(&method.id) { + found_pub_static = true; + visit::walk_method_helper(self, *method, ()); + } + } + 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_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, fd: &ast::FnDecl, b: &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, id, ()); + } + } + + fn visit_ty(&mut self, t: &ast::Ty, _: ()) { + match t.node { + ast::TyPath(ref p, _, path_id) => { + if self.path_is_private_type(path_id) { + self.tcx.sess.add_lint(lint::VisiblePrivateTypes, + path_id, 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) { + visit::walk_variant(self, v, g, ()); + } + } + + fn visit_struct_field(&mut self, s: &ast::StructField, _: ()) { + match s.node.kind { + // the only way to get here is by being inside a public + // struct/enum variant, so the only way to have a private + // field is with an explicit `priv`. + ast::NamedField(_, ast::Private) => {} + + _ => 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, and neither do view_items. (Making them no-ops stops us + // from traversing the whole AST without having to be super + // careful about our `walk_...` calls above.) + fn visit_view_item(&mut self, _: &ast::ViewItem, _: ()) {} + fn visit_block(&mut self, _: &ast::Block, _: ()) {} + fn visit_expr(&mut self, _: &ast::Expr, _: ()) {} +} + pub fn check_crate(tcx: ty::ctxt, method_map: &MethodMap, exp_map2: &resolve::ExportMap2, @@ -1225,5 +1471,14 @@ pub fn check_crate(tcx: ty::ctxt, } let EmbargoVisitor { exported_items, public_items, .. } = visitor; + + { + let mut visitor = VisiblePrivateTypesVisitor { + tcx: tcx, + exported_items: &exported_items, + public_items: &public_items + }; + visit::walk_crate(&mut visitor, krate, ()); + } return (exported_items, public_items); } diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs index 248ba593c1f..39989977d69 100644 --- a/src/libsyntax/visit.rs +++ b/src/libsyntax/visit.rs @@ -193,9 +193,11 @@ fn walk_explicit_self<E: Clone, V: Visitor<E>>(visitor: &mut V, } } -fn walk_trait_ref<E: Clone, V: Visitor<E>>(visitor: &mut V, - trait_ref: &TraitRef, - env: E) { +/// Like with walk_method_helper this doesn't correspond to a method +/// in Visitor, and so it gets a _helper suffix. +pub fn walk_trait_ref_helper<E: Clone, V: Visitor<E>>(visitor: &mut V, + trait_ref: &TraitRef, + env: E) { visitor.visit_path(&trait_ref.path, trait_ref.ref_id, env) } @@ -239,7 +241,8 @@ pub fn walk_item<E: Clone, V: Visitor<E>>(visitor: &mut V, item: &Item, env: E) ref methods) => { visitor.visit_generics(type_parameters, env.clone()); match *trait_reference { - Some(ref trait_reference) => walk_trait_ref(visitor, trait_reference, env.clone()), + Some(ref trait_reference) => walk_trait_ref_helper(visitor, + trait_reference, env.clone()), None => () } visitor.visit_ty(typ, env.clone()); @@ -459,7 +462,7 @@ pub fn walk_ty_param_bounds<E: Clone, V: Visitor<E>>(visitor: &mut V, for bound in bounds.iter() { match *bound { TraitTyParamBound(ref typ) => { - walk_trait_ref(visitor, typ, env.clone()) + walk_trait_ref_helper(visitor, typ, env.clone()) } RegionTyParamBound => {} } diff --git a/src/test/compile-fail/lint-dead-code-1.rs b/src/test/compile-fail/lint-dead-code-1.rs index b6965a003e0..629a203fcbb 100644 --- a/src/test/compile-fail/lint-dead-code-1.rs +++ b/src/test/compile-fail/lint-dead-code-1.rs @@ -11,6 +11,7 @@ #[no_std]; #[allow(unused_variable)]; #[allow(non_camel_case_types)]; +#[allow(visible_private_types)]; #[deny(dead_code)]; #[crate_type="lib"]; diff --git a/src/test/compile-fail/lint-visible-private-types.rs b/src/test/compile-fail/lint-visible-private-types.rs new file mode 100644 index 00000000000..6d77f8b324c --- /dev/null +++ b/src/test/compile-fail/lint-visible-private-types.rs @@ -0,0 +1,129 @@ +// 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. + +#[feature(struct_variant)]; +#[deny(visible_private_types)]; +#[allow(dead_code)]; +#[crate_type="lib"]; + +struct Private<T>; +pub struct Public<T>; + +impl Private<Public<int>> { + pub fn a(&self) -> Private<int> { fail!() } + fn b(&self) -> Private<int> { fail!() } + + pub fn c() -> Private<int> { fail!() } + fn d() -> Private<int> { fail!() } +} +impl Private<int> { + pub fn e(&self) -> Private<int> { fail!() } + fn f(&self) -> Private<int> { fail!() } +} + +impl Public<Private<int>> { + pub fn a(&self) -> Private<int> { fail!() } + fn b(&self) -> Private<int> { fail!() } + + pub fn c() -> Private<int> { fail!() } //~ ERROR private type in exported type signature + fn d() -> Private<int> { fail!() } +} +impl Public<int> { + pub fn e(&self) -> Private<int> { fail!() } //~ ERROR private type in exported type signature + fn f(&self) -> Private<int> { fail!() } +} + +pub fn x(_: Private<int>) {} //~ ERROR private type in exported type signature + +fn y(_: Private<int>) {} + + +pub struct Foo { + x: Private<int>, //~ ERROR private type in exported type signature + priv y: Private<int> +} + +struct Bar { + x: Private<int>, +} + +pub enum Baz { + Baz1(Private<int>), //~ ERROR private type in exported type signature + Baz2 { + x: Private<int>, //~ ERROR private type in exported type signature + priv y: Private<int> + }, + + priv Baz3(Private<int>), + priv Baz4 { + x: Private<int>, + } +} + +enum Qux { + Qux1(Private<int>), + Qux2 { + x: Private<int>, + } +} + +pub trait PubTrait { + fn foo(&self) -> Private<int> { fail!( )} //~ ERROR private type in exported type signature + fn bar(&self) -> Private<int>; //~ ERROR private type in exported type signature + fn baz() -> Private<int>; //~ ERROR private type in exported type signature +} + +impl PubTrait for Public<int> { + fn bar(&self) -> Private<int> { fail!() } + fn baz() -> Private<int> { fail!() } +} +impl PubTrait for Public<Private<int>> { + fn bar(&self) -> Private<int> { fail!() } + fn baz() -> Private<int> { fail!() } +} + +impl PubTrait for Private<int> { + fn bar(&self) -> Private<int> { fail!() } + fn baz() -> Private<int> { fail!() } +} +impl PubTrait for (Private<int>,) { + fn bar(&self) -> Private<int> { fail!() } + fn baz() -> Private<int> { fail!() } +} + + +trait PrivTrait { + fn foo(&self) -> Private<int> { fail!( )} + fn bar(&self) -> Private<int>; +} +impl PrivTrait for Private<int> { + fn bar(&self) -> Private<int> { fail!() } +} +impl PrivTrait for (Private<int>,) { + fn bar(&self) -> Private<int> { fail!() } +} + +pub trait ParamTrait<T> { + fn foo() -> T; +} + +impl ParamTrait<Private<int>> //~ ERROR private type in exported type signature + for Public<int> { + fn foo() -> Private<int> { fail!() } +} + +impl ParamTrait<Private<int>> for Private<int> { + fn foo() -> Private<int> { fail!( )} +} + +impl<T: ParamTrait<Private<int>>> //~ ERROR private type in exported type signature + ParamTrait<T> for Public<i8> { + fn foo() -> T { fail!() } +} |