diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs new file mode 100644 index 0000000000000..3065645db2798 --- /dev/null +++ b/src/librustc/lint/builtin.rs @@ -0,0 +1,1081 @@ +// 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Lints built in to rustc. + +use metadata::csearch; +use middle::def; +use middle::def::*; +use middle::pat_util; +use middle::trans::adt; // for `adt::is_ffi_safe` +use middle::ty; +use middle::typeck::astconv::{ast_ty_to_ty, AstConv}; +use middle::typeck::infer; +use middle::typeck; +use util::ppaux::{ty_to_str}; +use lint::Context; +use lint; + +use std::cmp; +use std::collections::HashMap; +use std::i16; +use std::i32; +use std::i64; +use std::i8; +use std::u16; +use std::u32; +use std::u64; +use std::u8; +use syntax::abi; +use syntax::ast_map; +use syntax::attr::AttrMetaMethods; +use syntax::attr; +use syntax::codemap::Span; +use syntax::parse::token; +use syntax::visit::Visitor; +use syntax::{ast, ast_util, visit}; + +pub fn check_while_true_expr(cx: &Context, e: &ast::Expr) { + match e.node { + ast::ExprWhile(cond, _) => { + match cond.node { + ast::ExprLit(lit) => { + match lit.node { + ast::LitBool(true) => { + cx.span_lint(lint::WhileTrue, + e.span, + "denote infinite loops with loop \ + { ... }"); + } + _ => {} + } + } + _ => () + } + } + _ => () + } +} + +pub fn check_unused_casts(cx: &Context, e: &ast::Expr) { + return match e.node { + ast::ExprCast(expr, ty) => { + let t_t = ast_ty_to_ty(cx, &infer::new_infer_ctxt(cx.tcx), ty); + if ty::get(ty::expr_ty(cx.tcx, expr)).sty == ty::get(t_t).sty { + cx.span_lint(lint::UnnecessaryTypecast, ty.span, + "unnecessary type cast"); + } + } + _ => () + }; +} + +pub fn check_type_limits(cx: &Context, e: &ast::Expr) { + return match e.node { + ast::ExprUnary(ast::UnNeg, ex) => { + match ex.node { + ast::ExprLit(lit) => { + match lit.node { + ast::LitUint(..) => { + cx.span_lint(lint::UnsignedNegate, e.span, + "negation of unsigned int literal may be unintentional"); + }, + _ => () + } + }, + _ => { + let t = ty::expr_ty(cx.tcx, ex); + match ty::get(t).sty { + ty::ty_uint(_) => { + cx.span_lint(lint::UnsignedNegate, e.span, + "negation of unsigned int variable may be unintentional"); + }, + _ => () + } + } + } + }, + ast::ExprBinary(binop, l, r) => { + if is_comparison(binop) && !check_limits(cx.tcx, binop, l, r) { + cx.span_lint(lint::TypeLimits, e.span, + "comparison is useless due to type limits"); + } + }, + ast::ExprLit(lit) => { + match ty::get(ty::expr_ty(cx.tcx, e)).sty { + ty::ty_int(t) => { + let int_type = if t == ast::TyI { + cx.tcx.sess.targ_cfg.int_type + } else { t }; + let (min, max) = int_ty_range(int_type); + let mut lit_val: i64 = match lit.node { + ast::LitInt(v, _) => v, + ast::LitUint(v, _) => v as i64, + ast::LitIntUnsuffixed(v) => v, + _ => fail!() + }; + if cx.negated_expr_id == e.id { + lit_val *= -1; + } + if lit_val < min || lit_val > max { + cx.span_lint(lint::TypeOverflow, e.span, + "literal out of range for its type"); + } + }, + ty::ty_uint(t) => { + let uint_type = if t == ast::TyU { + cx.tcx.sess.targ_cfg.uint_type + } else { t }; + let (min, max) = uint_ty_range(uint_type); + let lit_val: u64 = match lit.node { + ast::LitInt(v, _) => v as u64, + ast::LitUint(v, _) => v, + ast::LitIntUnsuffixed(v) => v as u64, + _ => fail!() + }; + if lit_val < min || lit_val > max { + cx.span_lint(lint::TypeOverflow, e.span, + "literal out of range for its type"); + } + }, + + _ => () + }; + }, + _ => () + }; + + fn is_valid(binop: ast::BinOp, v: T, + min: T, max: T) -> bool { + match binop { + ast::BiLt => v > min && v <= max, + ast::BiLe => v >= min && v < max, + ast::BiGt => v >= min && v < max, + ast::BiGe => v > min && v <= max, + ast::BiEq | ast::BiNe => v >= min && v <= max, + _ => fail!() + } + } + + fn rev_binop(binop: ast::BinOp) -> ast::BinOp { + match binop { + ast::BiLt => ast::BiGt, + ast::BiLe => ast::BiGe, + ast::BiGt => ast::BiLt, + ast::BiGe => ast::BiLe, + _ => binop + } + } + + // for int & uint, be conservative with the warnings, so that the + // warnings are consistent between 32- and 64-bit platforms + fn int_ty_range(int_ty: ast::IntTy) -> (i64, i64) { + match int_ty { + ast::TyI => (i64::MIN, i64::MAX), + ast::TyI8 => (i8::MIN as i64, i8::MAX as i64), + ast::TyI16 => (i16::MIN as i64, i16::MAX as i64), + ast::TyI32 => (i32::MIN as i64, i32::MAX as i64), + ast::TyI64 => (i64::MIN, i64::MAX) + } + } + + fn uint_ty_range(uint_ty: ast::UintTy) -> (u64, u64) { + match uint_ty { + ast::TyU => (u64::MIN, u64::MAX), + ast::TyU8 => (u8::MIN as u64, u8::MAX as u64), + ast::TyU16 => (u16::MIN as u64, u16::MAX as u64), + ast::TyU32 => (u32::MIN as u64, u32::MAX as u64), + ast::TyU64 => (u64::MIN, u64::MAX) + } + } + + fn check_limits(tcx: &ty::ctxt, binop: ast::BinOp, + l: &ast::Expr, r: &ast::Expr) -> bool { + let (lit, expr, swap) = match (&l.node, &r.node) { + (&ast::ExprLit(_), _) => (l, r, true), + (_, &ast::ExprLit(_)) => (r, l, false), + _ => return true + }; + // Normalize the binop so that the literal is always on the RHS in + // the comparison + let norm_binop = if swap { rev_binop(binop) } else { binop }; + match ty::get(ty::expr_ty(tcx, expr)).sty { + ty::ty_int(int_ty) => { + let (min, max) = int_ty_range(int_ty); + let lit_val: i64 = match lit.node { + ast::ExprLit(li) => match li.node { + ast::LitInt(v, _) => v, + ast::LitUint(v, _) => v as i64, + ast::LitIntUnsuffixed(v) => v, + _ => return true + }, + _ => fail!() + }; + is_valid(norm_binop, lit_val, min, max) + } + ty::ty_uint(uint_ty) => { + let (min, max): (u64, u64) = uint_ty_range(uint_ty); + let lit_val: u64 = match lit.node { + ast::ExprLit(li) => match li.node { + ast::LitInt(v, _) => v as u64, + ast::LitUint(v, _) => v, + ast::LitIntUnsuffixed(v) => v as u64, + _ => return true + }, + _ => fail!() + }; + is_valid(norm_binop, lit_val, min, max) + } + _ => true + } + } + + fn is_comparison(binop: ast::BinOp) -> bool { + match binop { + ast::BiEq | ast::BiLt | ast::BiLe | + ast::BiNe | ast::BiGe | ast::BiGt => true, + _ => false + } + } +} + +pub fn check_item_ctypes(cx: &Context, it: &ast::Item) { + fn check_ty(cx: &Context, ty: &ast::Ty) { + match ty.node { + ast::TyPath(_, _, id) => { + match cx.tcx.def_map.borrow().get_copy(&id) { + def::DefPrimTy(ast::TyInt(ast::TyI)) => { + cx.span_lint(lint::CTypes, ty.span, + "found rust type `int` in foreign module, while \ + libc::c_int or libc::c_long should be used"); + } + def::DefPrimTy(ast::TyUint(ast::TyU)) => { + cx.span_lint(lint::CTypes, ty.span, + "found rust type `uint` in foreign module, while \ + libc::c_uint or libc::c_ulong should be used"); + } + def::DefTy(def_id) => { + if !adt::is_ffi_safe(cx.tcx, def_id) { + cx.span_lint(lint::CTypes, ty.span, + "found enum type without foreign-function-safe \ + representation annotation in foreign module"); + // hmm... this message could be more helpful + } + } + _ => () + } + } + ast::TyPtr(ref mt) => { check_ty(cx, mt.ty) } + _ => {} + } + } + + fn check_foreign_fn(cx: &Context, decl: &ast::FnDecl) { + for input in decl.inputs.iter() { + check_ty(cx, input.ty); + } + check_ty(cx, decl.output) + } + + match it.node { + ast::ItemForeignMod(ref nmod) if nmod.abi != abi::RustIntrinsic => { + for ni in nmod.items.iter() { + match ni.node { + ast::ForeignItemFn(decl, _) => check_foreign_fn(cx, decl), + ast::ForeignItemStatic(t, _) => check_ty(cx, t) + } + } + } + _ => {/* nothing to do */ } + } +} + +pub fn check_heap_type(cx: &Context, span: Span, ty: ty::t) { + let xs = [lint::ManagedHeapMemory, lint::OwnedHeapMemory, lint::HeapMemory]; + for &lint in xs.iter() { + if cx.get_level(lint) == lint::Allow { continue } + + let mut n_box = 0; + let mut n_uniq = 0; + ty::fold_ty(cx.tcx, ty, |t| { + match ty::get(t).sty { + ty::ty_box(_) => { + n_box += 1; + } + ty::ty_uniq(_) | + ty::ty_trait(box ty::TyTrait { + store: ty::UniqTraitStore, .. + }) | + ty::ty_closure(box ty::ClosureTy { + store: ty::UniqTraitStore, + .. + }) => { + n_uniq += 1; + } + + _ => () + }; + t + }); + + if n_uniq > 0 && lint != lint::ManagedHeapMemory { + let s = ty_to_str(cx.tcx, ty); + let m = format!("type uses owned (Box type) pointers: {}", s); + cx.span_lint(lint, span, m.as_slice()); + } + + if n_box > 0 && lint != lint::OwnedHeapMemory { + let s = ty_to_str(cx.tcx, ty); + let m = format!("type uses managed (@ type) pointers: {}", s); + cx.span_lint(lint, span, m.as_slice()); + } + } +} + +pub fn check_heap_item(cx: &Context, it: &ast::Item) { + match it.node { + ast::ItemFn(..) | + ast::ItemTy(..) | + ast::ItemEnum(..) | + ast::ItemStruct(..) => check_heap_type(cx, it.span, + ty::node_id_to_type(cx.tcx, + it.id)), + _ => () + } + + // If it's a struct, we also have to check the fields' types + match it.node { + ast::ItemStruct(struct_def, _) => { + for struct_field in struct_def.fields.iter() { + check_heap_type(cx, struct_field.span, + ty::node_id_to_type(cx.tcx, + struct_field.node.id)); + } + } + _ => () + } +} + +struct RawPtrDerivingVisitor<'a> { + cx: &'a Context<'a> +} + +impl<'a> Visitor<()> for RawPtrDerivingVisitor<'a> { + fn visit_ty(&mut self, ty: &ast::Ty, _: ()) { + static MSG: &'static str = "use of `#[deriving]` with a raw pointer"; + match ty.node { + ast::TyPtr(..) => self.cx.span_lint(lint::RawPointerDeriving, ty.span, MSG), + _ => {} + } + visit::walk_ty(self, ty, ()); + } + // explicit override to a no-op to reduce code bloat + fn visit_expr(&mut self, _: &ast::Expr, _: ()) {} + fn visit_block(&mut self, _: &ast::Block, _: ()) {} +} + +pub fn check_raw_ptr_deriving(cx: &mut Context, item: &ast::Item) { + if !attr::contains_name(item.attrs.as_slice(), "automatically_derived") { + return + } + let did = match item.node { + ast::ItemImpl(..) => { + match ty::get(ty::node_id_to_type(cx.tcx, item.id)).sty { + ty::ty_enum(did, _) => did, + ty::ty_struct(did, _) => did, + _ => return, + } + } + _ => return, + }; + if !ast_util::is_local(did) { return } + let item = match cx.tcx.map.find(did.node) { + Some(ast_map::NodeItem(item)) => item, + _ => return, + }; + if !cx.checked_raw_pointers.insert(item.id) { return } + match item.node { + ast::ItemStruct(..) | ast::ItemEnum(..) => { + let mut visitor = RawPtrDerivingVisitor { cx: cx }; + visit::walk_item(&mut visitor, item, ()); + } + _ => {} + } +} + +pub fn check_unused_attribute(cx: &Context, attr: &ast::Attribute) { + static ATTRIBUTE_WHITELIST: &'static [&'static str] = &'static [ + // FIXME: #14408 whitelist docs since rustdoc looks at them + "doc", + + // FIXME: #14406 these are processed in trans, which happens after the + // lint pass + "address_insignificant", + "cold", + "inline", + "link", + "link_name", + "link_section", + "no_builtins", + "no_mangle", + "no_split_stack", + "packed", + "static_assert", + "thread_local", + + // not used anywhere (!?) but apparently we want to keep them around + "comment", + "desc", + "license", + + // FIXME: #14407 these are only looked at on-demand so we can't + // guarantee they'll have already been checked + "deprecated", + "experimental", + "frozen", + "locked", + "must_use", + "stable", + "unstable", + ]; + + static CRATE_ATTRS: &'static [&'static str] = &'static [ + "crate_type", + "feature", + "no_start", + "no_main", + "no_std", + "crate_id", + "desc", + "comment", + "license", + "copyright", + "no_builtins", + ]; + + for &name in ATTRIBUTE_WHITELIST.iter() { + if attr.check_name(name) { + break; + } + } + + if !attr::is_used(attr) { + cx.span_lint(lint::UnusedAttribute, attr.span, "unused attribute"); + if CRATE_ATTRS.contains(&attr.name().get()) { + let msg = match attr.node.style { + ast::AttrOuter => "crate-level attribute should be an inner \ + attribute: add an exclamation mark: #![foo]", + ast::AttrInner => "crate-level attribute should be in the \ + root module", + }; + cx.span_lint(lint::UnusedAttribute, attr.span, msg); + } + } +} + +pub fn check_heap_expr(cx: &Context, e: &ast::Expr) { + let ty = ty::expr_ty(cx.tcx, e); + check_heap_type(cx, e.span, ty); +} + +pub fn check_path_statement(cx: &Context, s: &ast::Stmt) { + match s.node { + ast::StmtSemi(expr, _) => { + match expr.node { + ast::ExprPath(_) => { + cx.span_lint(lint::PathStatement, + s.span, + "path statement with no effect"); + } + _ => {} + } + } + _ => () + } +} + +pub fn check_unused_result(cx: &Context, s: &ast::Stmt) { + let expr = match s.node { + ast::StmtSemi(expr, _) => expr, + _ => return + }; + let t = ty::expr_ty(cx.tcx, expr); + match ty::get(t).sty { + ty::ty_nil | ty::ty_bot | ty::ty_bool => return, + _ => {} + } + match expr.node { + ast::ExprRet(..) => return, + _ => {} + } + + let t = ty::expr_ty(cx.tcx, expr); + let mut warned = false; + match ty::get(t).sty { + ty::ty_struct(did, _) | + ty::ty_enum(did, _) => { + if ast_util::is_local(did) { + match cx.tcx.map.get(did.node) { + ast_map::NodeItem(it) => { + if attr::contains_name(it.attrs.as_slice(), + "must_use") { + cx.span_lint(lint::UnusedMustUse, s.span, + "unused result which must be used"); + warned = true; + } + } + _ => {} + } + } else { + csearch::get_item_attrs(&cx.tcx.sess.cstore, did, |attrs| { + if attr::contains_name(attrs.as_slice(), "must_use") { + cx.span_lint(lint::UnusedMustUse, s.span, + "unused result which must be used"); + warned = true; + } + }); + } + } + _ => {} + } + if !warned { + cx.span_lint(lint::UnusedResult, s.span, "unused result"); + } +} + +pub fn check_deprecated_owned_vector(cx: &Context, e: &ast::Expr) { + let t = ty::expr_ty(cx.tcx, e); + match ty::get(t).sty { + ty::ty_uniq(t) => match ty::get(t).sty { + ty::ty_vec(_, None) => { + cx.span_lint(lint::DeprecatedOwnedVector, e.span, + "use of deprecated `~[]` vector; replaced by `std::vec::Vec`") + } + _ => {} + }, + _ => {} + } +} + +pub fn check_item_non_camel_case_types(cx: &Context, it: &ast::Item) { + fn is_camel_case(ident: ast::Ident) -> bool { + let ident = token::get_ident(ident); + assert!(!ident.get().is_empty()); + let ident = ident.get().trim_chars('_'); + + // start with a non-lowercase letter rather than non-uppercase + // ones (some scripts don't have a concept of upper/lowercase) + !ident.char_at(0).is_lowercase() && !ident.contains_char('_') + } + + fn to_camel_case(s: &str) -> String { + s.split('_').flat_map(|word| word.chars().enumerate().map(|(i, c)| + if i == 0 { c.to_uppercase() } + else { c } + )).collect() + } + + fn check_case(cx: &Context, sort: &str, ident: ast::Ident, span: Span) { + let s = token::get_ident(ident); + + if !is_camel_case(ident) { + cx.span_lint(lint:: + NonCamelCaseTypes, span, + format!("{} `{}` should have a camel case name such as `{}`", + sort, s, to_camel_case(s.get())).as_slice()); + } + } + + match it.node { + ast::ItemTy(..) | ast::ItemStruct(..) => { + check_case(cx, "type", it.ident, it.span) + } + ast::ItemTrait(..) => { + check_case(cx, "trait", it.ident, it.span) + } + ast::ItemEnum(ref enum_definition, _) => { + check_case(cx, "type", it.ident, it.span); + for variant in enum_definition.variants.iter() { + check_case(cx, "variant", variant.node.name, variant.span); + } + } + _ => () + } +} + +pub fn check_snake_case(cx: &Context, sort: &str, ident: ast::Ident, span: Span) { + fn is_snake_case(ident: ast::Ident) -> bool { + let ident = token::get_ident(ident); + assert!(!ident.get().is_empty()); + let ident = ident.get().trim_chars('_'); + + let mut allow_underscore = true; + ident.chars().all(|c| { + allow_underscore = match c { + c if c.is_lowercase() || c.is_digit() => true, + '_' if allow_underscore => false, + _ => return false, + }; + true + }) + } + + fn to_snake_case(str: &str) -> String { + let mut words = vec![]; + for s in str.split('_') { + let mut buf = String::new(); + if s.is_empty() { continue; } + for ch in s.chars() { + if !buf.is_empty() && ch.is_uppercase() { + words.push(buf); + buf = String::new(); + } + buf.push_char(ch.to_lowercase()); + } + words.push(buf); + } + words.connect("_") + } + + let s = token::get_ident(ident); + + if !is_snake_case(ident) { + cx.span_lint(lint::NonSnakeCaseFunctions, span, + format!("{} `{}` should have a snake case name such as `{}`", + sort, s, to_snake_case(s.get())).as_slice()); + } +} + +pub fn check_item_non_uppercase_statics(cx: &Context, it: &ast::Item) { + match it.node { + // only check static constants + ast::ItemStatic(_, ast::MutImmutable, _) => { + let s = token::get_ident(it.ident); + // check for lowercase letters rather than non-uppercase + // ones (some scripts don't have a concept of + // upper/lowercase) + if s.get().chars().any(|c| c.is_lowercase()) { + cx.span_lint(lint::NonUppercaseStatics, it.span, + format!("static constant `{}` should have an uppercase name \ + such as `{}`", s.get(), + s.get().chars().map(|c| c.to_uppercase()) + .collect::().as_slice()).as_slice()); + } + } + _ => {} + } +} + +pub fn check_pat_non_uppercase_statics(cx: &Context, p: &ast::Pat) { + // Lint for constants that look like binding identifiers (#7526) + match (&p.node, cx.tcx.def_map.borrow().find(&p.id)) { + (&ast::PatIdent(_, ref path, _), Some(&def::DefStatic(_, false))) => { + // last identifier alone is right choice for this lint. + let ident = path.segments.last().unwrap().identifier; + let s = token::get_ident(ident); + if s.get().chars().any(|c| c.is_lowercase()) { + cx.span_lint(lint::NonUppercasePatternStatics, path.span, + format!("static constant in pattern `{}` should have an uppercase \ + name such as `{}`", s.get(), + s.get().chars().map(|c| c.to_uppercase()) + .collect::().as_slice()).as_slice()); + } + } + _ => {} + } +} + +pub fn check_pat_uppercase_variable(cx: &Context, p: &ast::Pat) { + match &p.node { + &ast::PatIdent(_, ref path, _) => { + match cx.tcx.def_map.borrow().find(&p.id) { + Some(&def::DefLocal(_, _)) | Some(&def::DefBinding(_, _)) | + Some(&def::DefArg(_, _)) => { + // last identifier alone is right choice for this lint. + let ident = path.segments.last().unwrap().identifier; + let s = token::get_ident(ident); + if s.get().len() > 0 && s.get().char_at(0).is_uppercase() { + cx.span_lint(lint:: + UppercaseVariables, + path.span, + "variable names should start with a lowercase character"); + } + } + _ => {} + } + } + _ => {} + } +} + +pub fn check_struct_uppercase_variable(cx: &Context, s: &ast::StructDef) { + for sf in s.fields.iter() { + match sf.node { + ast::StructField_ { kind: ast::NamedField(ident, _), .. } => { + let s = token::get_ident(ident); + if s.get().char_at(0).is_uppercase() { + cx.span_lint(lint:: + UppercaseVariables, + sf.span, + "structure field names should start with a lowercase character"); + } + } + _ => {} + } + } +} + +pub fn check_unnecessary_parens_core(cx: &Context, value: &ast::Expr, msg: &str) { + match value.node { + ast::ExprParen(_) => { + cx.span_lint(lint::UnnecessaryParens, value.span, + format!("unnecessary parentheses around {}", + msg).as_slice()) + } + _ => {} + } +} + +pub fn check_unnecessary_parens_expr(cx: &Context, e: &ast::Expr) { + let (value, msg) = match e.node { + ast::ExprIf(cond, _, _) => (cond, "`if` condition"), + ast::ExprWhile(cond, _) => (cond, "`while` condition"), + ast::ExprMatch(head, _) => (head, "`match` head expression"), + ast::ExprRet(Some(value)) => (value, "`return` value"), + ast::ExprAssign(_, value) => (value, "assigned value"), + ast::ExprAssignOp(_, _, value) => (value, "assigned value"), + _ => return + }; + check_unnecessary_parens_core(cx, value, msg); +} + +pub fn check_unnecessary_parens_stmt(cx: &Context, s: &ast::Stmt) { + let (value, msg) = match s.node { + ast::StmtDecl(decl, _) => match decl.node { + ast::DeclLocal(local) => match local.init { + Some(value) => (value, "assigned value"), + None => return + }, + _ => return + }, + _ => return + }; + check_unnecessary_parens_core(cx, value, msg); +} + +pub fn check_unused_unsafe(cx: &Context, e: &ast::Expr) { + match e.node { + // Don't warn about generated blocks, that'll just pollute the output. + ast::ExprBlock(ref blk) => { + if blk.rules == ast::UnsafeBlock(ast::UserProvided) && + !cx.tcx.used_unsafe.borrow().contains(&blk.id) { + cx.span_lint(lint::UnusedUnsafe, blk.span, + "unnecessary `unsafe` block"); + } + } + _ => () + } +} + +pub fn check_unsafe_block(cx: &Context, e: &ast::Expr) { + match e.node { + // Don't warn about generated blocks, that'll just pollute the output. + ast::ExprBlock(ref blk) if blk.rules == ast::UnsafeBlock(ast::UserProvided) => { + cx.span_lint(lint::UnsafeBlock, blk.span, "usage of an `unsafe` block"); + } + _ => () + } +} + +pub fn check_unused_mut_pat(cx: &Context, pats: &[@ast::Pat]) { + // collect all mutable pattern and group their NodeIDs by their Identifier to + // avoid false warnings in match arms with multiple patterns + let mut mutables = HashMap::new(); + for &p in pats.iter() { + pat_util::pat_bindings(&cx.tcx.def_map, p, |mode, id, _, path| { + match mode { + ast::BindByValue(ast::MutMutable) => { + if path.segments.len() != 1 { + cx.tcx.sess.span_bug(p.span, + "mutable binding that doesn't consist \ + of exactly one segment"); + } + let ident = path.segments.get(0).identifier; + if !token::get_ident(ident).get().starts_with("_") { + mutables.insert_or_update_with(ident.name as uint, vec!(id), |_, old| { + old.push(id); + }); + } + } + _ => { + } + } + }); + } + + let used_mutables = cx.tcx.used_mut_nodes.borrow(); + for (_, v) in mutables.iter() { + if !v.iter().any(|e| used_mutables.contains(e)) { + cx.span_lint(lint::UnusedMut, cx.tcx.map.span(*v.get(0)), + "variable does not need to be mutable"); + } + } +} + +enum Allocation { + VectorAllocation, + BoxAllocation +} + +pub fn check_unnecessary_allocation(cx: &Context, e: &ast::Expr) { + // Warn if string and vector literals with sigils, or boxing expressions, + // are immediately borrowed. + let allocation = match e.node { + ast::ExprVstore(e2, ast::ExprVstoreUniq) => { + match e2.node { + ast::ExprLit(lit) if ast_util::lit_is_str(lit) => { + VectorAllocation + } + ast::ExprVec(..) => VectorAllocation, + _ => return + } + } + ast::ExprUnary(ast::UnUniq, _) | + ast::ExprUnary(ast::UnBox, _) => BoxAllocation, + + _ => return + }; + + let report = |msg| { + cx.span_lint(lint::UnnecessaryAllocation, e.span, msg); + }; + + match cx.tcx.adjustments.borrow().find(&e.id) { + Some(adjustment) => { + match *adjustment { + ty::AutoDerefRef(ty::AutoDerefRef { autoref, .. }) => { + match (allocation, autoref) { + (VectorAllocation, Some(ty::AutoBorrowVec(..))) => { + report("unnecessary allocation, the sigil can be \ + removed"); + } + (BoxAllocation, + Some(ty::AutoPtr(_, ast::MutImmutable))) => { + report("unnecessary allocation, use & instead"); + } + (BoxAllocation, + Some(ty::AutoPtr(_, ast::MutMutable))) => { + report("unnecessary allocation, use &mut \ + instead"); + } + _ => () + } + } + _ => {} + } + } + + _ => () + } +} + +pub fn check_missing_doc_attrs(cx: &Context, + id: Option, + attrs: &[ast::Attribute], + sp: Span, + desc: &'static str) { + // If we're building a test harness, then warning about + // documentation is probably not really relevant right now. + if cx.tcx.sess.opts.test { return } + + // `#[doc(hidden)]` disables missing_doc check. + if cx.is_doc_hidden { return } + + // Only check publicly-visible items, using the result from the privacy pass. It's an option so + // the crate root can also use this function (it doesn't have a NodeId). + match id { + Some(ref id) if !cx.exported_items.contains(id) => return, + _ => () + } + + let has_doc = attrs.iter().any(|a| { + match a.node.value.node { + ast::MetaNameValue(ref name, _) if name.equiv(&("doc")) => true, + _ => false + } + }); + if !has_doc { + cx.span_lint(lint::MissingDoc, + sp, + format!("missing documentation for {}", + desc).as_slice()); + } +} + +pub fn check_missing_doc_item(cx: &Context, it: &ast::Item) { + let desc = match it.node { + ast::ItemFn(..) => "a function", + ast::ItemMod(..) => "a module", + ast::ItemEnum(..) => "an enum", + ast::ItemStruct(..) => "a struct", + ast::ItemTrait(..) => "a trait", + _ => return + }; + check_missing_doc_attrs(cx, + Some(it.id), + it.attrs.as_slice(), + it.span, + desc); +} + +pub fn check_missing_doc_method(cx: &Context, m: &ast::Method) { + // If the method is an impl for a trait, don't doc. + if lint::method_context(cx, m) == lint::TraitImpl { return; } + + // Otherwise, doc according to privacy. This will also check + // doc for default methods defined on traits. + check_missing_doc_attrs(cx, + Some(m.id), + m.attrs.as_slice(), + m.span, + "a method"); +} + +pub fn check_missing_doc_ty_method(cx: &Context, tm: &ast::TypeMethod) { + check_missing_doc_attrs(cx, + Some(tm.id), + tm.attrs.as_slice(), + tm.span, + "a type method"); +} + +pub fn check_missing_doc_struct_field(cx: &Context, sf: &ast::StructField) { + match sf.node.kind { + ast::NamedField(_, vis) if vis == ast::Public => + check_missing_doc_attrs(cx, + Some(cx.cur_struct_def_id), + sf.node.attrs.as_slice(), + sf.span, + "a struct field"), + _ => {} + } +} + +pub fn check_missing_doc_variant(cx: &Context, v: &ast::Variant) { + check_missing_doc_attrs(cx, + Some(v.node.id), + v.node.attrs.as_slice(), + v.span, + "a variant"); +} + +/// Checks for use of items with #[deprecated], #[experimental] and +/// #[unstable] (or none of them) attributes. +pub fn check_stability(cx: &Context, e: &ast::Expr) { + let id = match e.node { + ast::ExprPath(..) | ast::ExprStruct(..) => { + match cx.tcx.def_map.borrow().find(&e.id) { + Some(&def) => def.def_id(), + None => return + } + } + ast::ExprMethodCall(..) => { + let method_call = typeck::MethodCall::expr(e.id); + match cx.tcx.method_map.borrow().find(&method_call) { + Some(method) => { + match method.origin { + typeck::MethodStatic(def_id) => { + // If this implements a trait method, get def_id + // of the method inside trait definition. + // Otherwise, use the current def_id (which refers + // to the method inside impl). + ty::trait_method_of_method( + cx.tcx, def_id).unwrap_or(def_id) + } + typeck::MethodParam(typeck::MethodParam { + trait_id: trait_id, + method_num: index, + .. + }) + | typeck::MethodObject(typeck::MethodObject { + trait_id: trait_id, + method_num: index, + .. + }) => ty::trait_method(cx.tcx, trait_id, index).def_id + } + } + None => return + } + } + _ => return + }; + + let stability = if ast_util::is_local(id) { + // this crate + let s = cx.tcx.map.with_attrs(id.node, |attrs| { + attrs.map(|a| attr::find_stability(a.as_slice())) + }); + match s { + Some(s) => s, + + // no possibility of having attributes + // (e.g. it's a local variable), so just + // ignore it. + None => return + } + } else { + // cross-crate + + let mut s = None; + // run through all the attributes and take the first + // stability one. + csearch::get_item_attrs(&cx.tcx.sess.cstore, id, |attrs| { + if s.is_none() { + s = attr::find_stability(attrs.as_slice()) + } + }); + s + }; + + let (lint, label) = match stability { + // no stability attributes == Unstable + None => (lint::Unstable, "unmarked"), + Some(attr::Stability { level: attr::Unstable, .. }) => + (lint::Unstable, "unstable"), + Some(attr::Stability { level: attr::Experimental, .. }) => + (lint::Experimental, "experimental"), + Some(attr::Stability { level: attr::Deprecated, .. }) => + (lint::Deprecated, "deprecated"), + _ => return + }; + + let msg = match stability { + Some(attr::Stability { text: Some(ref s), .. }) => { + format!("use of {} item: {}", label, *s) + } + _ => format!("use of {} item", label) + }; + + cx.span_lint(lint, e.span, msg.as_slice()); +} + +pub fn check_enum_variant_sizes(cx: &mut Context, it: &ast::Item) { + match it.node { + ast::ItemEnum(..) => { + match cx.cur.find(&(lint::VariantSizeDifference as uint)) { + Some(&(lvl, src)) if lvl != lint::Allow => { + cx.node_levels.insert((it.id, lint::VariantSizeDifference), (lvl, src)); + }, + _ => { } + } + }, + _ => { } + } +} diff --git a/src/librustc/lint/mod.rs b/src/librustc/lint/mod.rs index c2fad75d6b89b..e60726f6d6b7c 100644 --- a/src/librustc/lint/mod.rs +++ b/src/librustc/lint/mod.rs @@ -36,45 +36,28 @@ #![allow(non_camel_case_types)] use driver::session; -use metadata::csearch; use middle::dead::DEAD_CODE_LINT_STR; -use middle::def; -use middle::def::*; -use middle::pat_util; use middle::privacy; -use middle::trans::adt; // for `adt::is_ffi_safe` use middle::ty; -use middle::typeck::astconv::{ast_ty_to_ty, AstConv}; +use middle::typeck::astconv::AstConv; use middle::typeck::infer; -use middle::typeck; -use util::ppaux::{ty_to_str}; use util::nodemap::NodeSet; -use std::cmp; use std::collections::HashMap; -use std::i16; -use std::i32; -use std::i64; -use std::i8; use std::rc::Rc; use std::gc::Gc; use std::to_str::ToStr; -use std::u16; -use std::u32; -use std::u64; -use std::u8; use std::collections::SmallIntMap; -use syntax::abi; -use syntax::ast_map; use syntax::ast_util::IdVisitingOperation; use syntax::attr::AttrMetaMethods; use syntax::attr; use syntax::codemap::Span; use syntax::parse::token::InternedString; -use syntax::parse::token; use syntax::visit::Visitor; use syntax::{ast, ast_util, visit}; +mod builtin; + #[deriving(Clone, Show, PartialEq, PartialOrd, Eq, Ord, Hash)] pub enum Lint { CTypes, @@ -697,898 +680,6 @@ pub fn contains_lint(attrs: &[ast::Attribute], false } -fn check_while_true_expr(cx: &Context, e: &ast::Expr) { - match e.node { - ast::ExprWhile(cond, _) => { - match cond.node { - ast::ExprLit(lit) => { - match lit.node { - ast::LitBool(true) => { - cx.span_lint(WhileTrue, - e.span, - "denote infinite loops with loop \ - { ... }"); - } - _ => {} - } - } - _ => () - } - } - _ => () - } -} -impl<'a> AstConv for Context<'a>{ - fn tcx<'a>(&'a self) -> &'a ty::ctxt { self.tcx } - - fn get_item_ty(&self, id: ast::DefId) -> ty::Polytype { - ty::lookup_item_type(self.tcx, id) - } - - fn get_trait_def(&self, id: ast::DefId) -> Rc { - ty::lookup_trait_def(self.tcx, id) - } - - fn ty_infer(&self, _span: Span) -> ty::t { - infer::new_infer_ctxt(self.tcx).next_ty_var() - } -} - - -fn check_unused_casts(cx: &Context, e: &ast::Expr) { - return match e.node { - ast::ExprCast(expr, ty) => { - let t_t = ast_ty_to_ty(cx, &infer::new_infer_ctxt(cx.tcx), &*ty); - if ty::get(ty::expr_ty(cx.tcx, &*expr)).sty == ty::get(t_t).sty { - cx.span_lint(UnnecessaryTypecast, ty.span, - "unnecessary type cast"); - } - } - _ => () - }; -} - -fn check_type_limits(cx: &Context, e: &ast::Expr) { - return match e.node { - ast::ExprUnary(ast::UnNeg, ex) => { - match ex.node { - ast::ExprLit(lit) => { - match lit.node { - ast::LitUint(..) => { - cx.span_lint(UnsignedNegate, e.span, - "negation of unsigned int literal may be unintentional"); - }, - _ => () - } - }, - _ => { - let t = ty::expr_ty(cx.tcx, &*ex); - match ty::get(t).sty { - ty::ty_uint(_) => { - cx.span_lint(UnsignedNegate, e.span, - "negation of unsigned int variable may be unintentional"); - }, - _ => () - } - } - } - }, - ast::ExprBinary(binop, l, r) => { - if is_comparison(binop) && !check_limits(cx.tcx, binop, &*l, &*r) { - cx.span_lint(TypeLimits, e.span, - "comparison is useless due to type limits"); - } - }, - ast::ExprLit(lit) => { - match ty::get(ty::expr_ty(cx.tcx, e)).sty { - ty::ty_int(t) => { - let int_type = if t == ast::TyI { - cx.tcx.sess.targ_cfg.int_type - } else { t }; - let (min, max) = int_ty_range(int_type); - let mut lit_val: i64 = match lit.node { - ast::LitInt(v, _) => v, - ast::LitUint(v, _) => v as i64, - ast::LitIntUnsuffixed(v) => v, - _ => fail!() - }; - if cx.negated_expr_id == e.id { - lit_val *= -1; - } - if lit_val < min || lit_val > max { - cx.span_lint(TypeOverflow, e.span, - "literal out of range for its type"); - } - }, - ty::ty_uint(t) => { - let uint_type = if t == ast::TyU { - cx.tcx.sess.targ_cfg.uint_type - } else { t }; - let (min, max) = uint_ty_range(uint_type); - let lit_val: u64 = match lit.node { - ast::LitByte(_v) => return, // _v is u8, within range by definition - ast::LitInt(v, _) => v as u64, - ast::LitUint(v, _) => v, - ast::LitIntUnsuffixed(v) => v as u64, - _ => fail!() - }; - if lit_val < min || lit_val > max { - cx.span_lint(TypeOverflow, e.span, - "literal out of range for its type"); - } - }, - - _ => () - }; - }, - _ => () - }; - - fn is_valid(binop: ast::BinOp, v: T, - min: T, max: T) -> bool { - match binop { - ast::BiLt => v > min && v <= max, - ast::BiLe => v >= min && v < max, - ast::BiGt => v >= min && v < max, - ast::BiGe => v > min && v <= max, - ast::BiEq | ast::BiNe => v >= min && v <= max, - _ => fail!() - } - } - - fn rev_binop(binop: ast::BinOp) -> ast::BinOp { - match binop { - ast::BiLt => ast::BiGt, - ast::BiLe => ast::BiGe, - ast::BiGt => ast::BiLt, - ast::BiGe => ast::BiLe, - _ => binop - } - } - - // for int & uint, be conservative with the warnings, so that the - // warnings are consistent between 32- and 64-bit platforms - fn int_ty_range(int_ty: ast::IntTy) -> (i64, i64) { - match int_ty { - ast::TyI => (i64::MIN, i64::MAX), - ast::TyI8 => (i8::MIN as i64, i8::MAX as i64), - ast::TyI16 => (i16::MIN as i64, i16::MAX as i64), - ast::TyI32 => (i32::MIN as i64, i32::MAX as i64), - ast::TyI64 => (i64::MIN, i64::MAX) - } - } - - fn uint_ty_range(uint_ty: ast::UintTy) -> (u64, u64) { - match uint_ty { - ast::TyU => (u64::MIN, u64::MAX), - ast::TyU8 => (u8::MIN as u64, u8::MAX as u64), - ast::TyU16 => (u16::MIN as u64, u16::MAX as u64), - ast::TyU32 => (u32::MIN as u64, u32::MAX as u64), - ast::TyU64 => (u64::MIN, u64::MAX) - } - } - - fn check_limits(tcx: &ty::ctxt, binop: ast::BinOp, - l: &ast::Expr, r: &ast::Expr) -> bool { - let (lit, expr, swap) = match (&l.node, &r.node) { - (&ast::ExprLit(_), _) => (l, r, true), - (_, &ast::ExprLit(_)) => (r, l, false), - _ => return true - }; - // Normalize the binop so that the literal is always on the RHS in - // the comparison - let norm_binop = if swap { rev_binop(binop) } else { binop }; - match ty::get(ty::expr_ty(tcx, expr)).sty { - ty::ty_int(int_ty) => { - let (min, max) = int_ty_range(int_ty); - let lit_val: i64 = match lit.node { - ast::ExprLit(li) => match li.node { - ast::LitInt(v, _) => v, - ast::LitUint(v, _) => v as i64, - ast::LitIntUnsuffixed(v) => v, - _ => return true - }, - _ => fail!() - }; - is_valid(norm_binop, lit_val, min, max) - } - ty::ty_uint(uint_ty) => { - let (min, max): (u64, u64) = uint_ty_range(uint_ty); - let lit_val: u64 = match lit.node { - ast::ExprLit(li) => match li.node { - ast::LitInt(v, _) => v as u64, - ast::LitUint(v, _) => v, - ast::LitIntUnsuffixed(v) => v as u64, - _ => return true - }, - _ => fail!() - }; - is_valid(norm_binop, lit_val, min, max) - } - _ => true - } - } - - fn is_comparison(binop: ast::BinOp) -> bool { - match binop { - ast::BiEq | ast::BiLt | ast::BiLe | - ast::BiNe | ast::BiGe | ast::BiGt => true, - _ => false - } - } -} - -fn check_item_ctypes(cx: &Context, it: &ast::Item) { - fn check_ty(cx: &Context, ty: &ast::Ty) { - match ty.node { - ast::TyPath(_, _, id) => { - match cx.tcx.def_map.borrow().get_copy(&id) { - def::DefPrimTy(ast::TyInt(ast::TyI)) => { - cx.span_lint(CTypes, ty.span, - "found rust type `int` in foreign module, while \ - libc::c_int or libc::c_long should be used"); - } - def::DefPrimTy(ast::TyUint(ast::TyU)) => { - cx.span_lint(CTypes, ty.span, - "found rust type `uint` in foreign module, while \ - libc::c_uint or libc::c_ulong should be used"); - } - def::DefTy(def_id) => { - if !adt::is_ffi_safe(cx.tcx, def_id) { - cx.span_lint(CTypes, ty.span, - "found enum type without foreign-function-safe \ - representation annotation in foreign module"); - // hmm... this message could be more helpful - } - } - _ => () - } - } - ast::TyPtr(ref mt) => { check_ty(cx, &*mt.ty) } - _ => {} - } - } - - fn check_foreign_fn(cx: &Context, decl: &ast::FnDecl) { - for input in decl.inputs.iter() { - check_ty(cx, &*input.ty); - } - check_ty(cx, &*decl.output) - } - - match it.node { - ast::ItemForeignMod(ref nmod) if nmod.abi != abi::RustIntrinsic => { - for ni in nmod.items.iter() { - match ni.node { - ast::ForeignItemFn(decl, _) => check_foreign_fn(cx, &*decl), - ast::ForeignItemStatic(t, _) => check_ty(cx, &*t) - } - } - } - _ => {/* nothing to do */ } - } -} - -fn check_heap_type(cx: &Context, span: Span, ty: ty::t) { - let xs = [ManagedHeapMemory, OwnedHeapMemory, HeapMemory]; - for &lint in xs.iter() { - if cx.get_level(lint) == Allow { continue } - - let mut n_box = 0; - let mut n_uniq = 0; - ty::fold_ty(cx.tcx, ty, |t| { - match ty::get(t).sty { - ty::ty_box(_) => { - n_box += 1; - } - ty::ty_uniq(_) | - ty::ty_closure(box ty::ClosureTy { - store: ty::UniqTraitStore, - .. - }) => { - n_uniq += 1; - } - - _ => () - }; - t - }); - - if n_uniq > 0 && lint != ManagedHeapMemory { - let s = ty_to_str(cx.tcx, ty); - let m = format!("type uses owned (Box type) pointers: {}", s); - cx.span_lint(lint, span, m.as_slice()); - } - - if n_box > 0 && lint != OwnedHeapMemory { - let s = ty_to_str(cx.tcx, ty); - let m = format!("type uses managed (@ type) pointers: {}", s); - cx.span_lint(lint, span, m.as_slice()); - } - } -} - -fn check_heap_item(cx: &Context, it: &ast::Item) { - match it.node { - ast::ItemFn(..) | - ast::ItemTy(..) | - ast::ItemEnum(..) | - ast::ItemStruct(..) => check_heap_type(cx, it.span, - ty::node_id_to_type(cx.tcx, - it.id)), - _ => () - } - - // If it's a struct, we also have to check the fields' types - match it.node { - ast::ItemStruct(struct_def, _) => { - for struct_field in struct_def.fields.iter() { - check_heap_type(cx, struct_field.span, - ty::node_id_to_type(cx.tcx, - struct_field.node.id)); - } - } - _ => () - } -} - -struct RawPtrDerivingVisitor<'a> { - cx: &'a Context<'a> -} - -impl<'a> Visitor<()> for RawPtrDerivingVisitor<'a> { - fn visit_ty(&mut self, ty: &ast::Ty, _: ()) { - static MSG: &'static str = "use of `#[deriving]` with a raw pointer"; - match ty.node { - ast::TyPtr(..) => self.cx.span_lint(RawPointerDeriving, ty.span, MSG), - _ => {} - } - visit::walk_ty(self, ty, ()); - } - // explicit override to a no-op to reduce code bloat - fn visit_expr(&mut self, _: &ast::Expr, _: ()) {} - fn visit_block(&mut self, _: &ast::Block, _: ()) {} -} - -fn check_raw_ptr_deriving(cx: &mut Context, item: &ast::Item) { - if !attr::contains_name(item.attrs.as_slice(), "automatically_derived") { - return - } - let did = match item.node { - ast::ItemImpl(..) => { - match ty::get(ty::node_id_to_type(cx.tcx, item.id)).sty { - ty::ty_enum(did, _) => did, - ty::ty_struct(did, _) => did, - _ => return, - } - } - _ => return, - }; - if !ast_util::is_local(did) { return } - let item = match cx.tcx.map.find(did.node) { - Some(ast_map::NodeItem(item)) => item, - _ => return, - }; - if !cx.checked_raw_pointers.insert(item.id) { return } - match item.node { - ast::ItemStruct(..) | ast::ItemEnum(..) => { - let mut visitor = RawPtrDerivingVisitor { cx: cx }; - visit::walk_item(&mut visitor, &*item, ()); - } - _ => {} - } -} - -fn check_unused_attribute(cx: &Context, attr: &ast::Attribute) { - static ATTRIBUTE_WHITELIST: &'static [&'static str] = &'static [ - // FIXME: #14408 whitelist docs since rustdoc looks at them - "doc", - - // FIXME: #14406 these are processed in trans, which happens after the - // lint pass - "cold", - "inline", - "link", - "link_name", - "link_section", - "no_builtins", - "no_mangle", - "no_split_stack", - "packed", - "static_assert", - "thread_local", - - // not used anywhere (!?) but apparently we want to keep them around - "comment", - "desc", - "license", - - // FIXME: #14407 these are only looked at on-demand so we can't - // guarantee they'll have already been checked - "deprecated", - "experimental", - "frozen", - "locked", - "must_use", - "stable", - "unstable", - ]; - - static CRATE_ATTRS: &'static [&'static str] = &'static [ - "crate_type", - "feature", - "no_start", - "no_main", - "no_std", - "crate_id", - "desc", - "comment", - "license", - "copyright", - "no_builtins", - ]; - - for &name in ATTRIBUTE_WHITELIST.iter() { - if attr.check_name(name) { - break; - } - } - - if !attr::is_used(attr) { - cx.span_lint(UnusedAttribute, attr.span, "unused attribute"); - if CRATE_ATTRS.contains(&attr.name().get()) { - let msg = match attr.node.style { - ast::AttrOuter => "crate-level attribute should be an inner \ - attribute: add an exclamation mark: #![foo]", - ast::AttrInner => "crate-level attribute should be in the \ - root module", - }; - cx.span_lint(UnusedAttribute, attr.span, msg); - } - } -} - -fn check_heap_expr(cx: &Context, e: &ast::Expr) { - let ty = ty::expr_ty(cx.tcx, e); - check_heap_type(cx, e.span, ty); -} - -fn check_path_statement(cx: &Context, s: &ast::Stmt) { - match s.node { - ast::StmtSemi(expr, _) => { - match expr.node { - ast::ExprPath(_) => { - cx.span_lint(PathStatement, - s.span, - "path statement with no effect"); - } - _ => {} - } - } - _ => () - } -} - -fn check_unused_result(cx: &Context, s: &ast::Stmt) { - let expr = match s.node { - ast::StmtSemi(expr, _) => expr, - _ => return - }; - let t = ty::expr_ty(cx.tcx, &*expr); - match ty::get(t).sty { - ty::ty_nil | ty::ty_bot | ty::ty_bool => return, - _ => {} - } - match expr.node { - ast::ExprRet(..) => return, - _ => {} - } - - let t = ty::expr_ty(cx.tcx, &*expr); - let mut warned = false; - match ty::get(t).sty { - ty::ty_struct(did, _) | - ty::ty_enum(did, _) => { - if ast_util::is_local(did) { - match cx.tcx.map.get(did.node) { - ast_map::NodeItem(it) => { - if attr::contains_name(it.attrs.as_slice(), - "must_use") { - cx.span_lint(UnusedMustUse, s.span, - "unused result which must be used"); - warned = true; - } - } - _ => {} - } - } else { - csearch::get_item_attrs(&cx.tcx.sess.cstore, did, |attrs| { - if attr::contains_name(attrs.as_slice(), "must_use") { - cx.span_lint(UnusedMustUse, s.span, - "unused result which must be used"); - warned = true; - } - }); - } - } - _ => {} - } - if !warned { - cx.span_lint(UnusedResult, s.span, "unused result"); - } -} - -fn check_item_non_camel_case_types(cx: &Context, it: &ast::Item) { - fn is_camel_case(ident: ast::Ident) -> bool { - let ident = token::get_ident(ident); - assert!(!ident.get().is_empty()); - let ident = ident.get().trim_chars('_'); - - // start with a non-lowercase letter rather than non-uppercase - // ones (some scripts don't have a concept of upper/lowercase) - !ident.char_at(0).is_lowercase() && !ident.contains_char('_') - } - - fn to_camel_case(s: &str) -> String { - s.split('_').flat_map(|word| word.chars().enumerate().map(|(i, c)| - if i == 0 { c.to_uppercase() } - else { c } - )).collect() - } - - fn check_case(cx: &Context, sort: &str, ident: ast::Ident, span: Span) { - let s = token::get_ident(ident); - - if !is_camel_case(ident) { - cx.span_lint( - NonCamelCaseTypes, span, - format!("{} `{}` should have a camel case name such as `{}`", - sort, s, to_camel_case(s.get())).as_slice()); - } - } - - match it.node { - ast::ItemTy(..) | ast::ItemStruct(..) => { - check_case(cx, "type", it.ident, it.span) - } - ast::ItemTrait(..) => { - check_case(cx, "trait", it.ident, it.span) - } - ast::ItemEnum(ref enum_definition, _) => { - check_case(cx, "type", it.ident, it.span); - for variant in enum_definition.variants.iter() { - check_case(cx, "variant", variant.node.name, variant.span); - } - } - _ => () - } -} - -fn check_snake_case(cx: &Context, sort: &str, ident: ast::Ident, span: Span) { - fn is_snake_case(ident: ast::Ident) -> bool { - let ident = token::get_ident(ident); - assert!(!ident.get().is_empty()); - let ident = ident.get().trim_chars('_'); - - let mut allow_underscore = true; - ident.chars().all(|c| { - allow_underscore = match c { - c if c.is_lowercase() || c.is_digit() => true, - '_' if allow_underscore => false, - _ => return false, - }; - true - }) - } - - fn to_snake_case(str: &str) -> String { - let mut words = vec![]; - for s in str.split('_') { - let mut buf = String::new(); - if s.is_empty() { continue; } - for ch in s.chars() { - if !buf.is_empty() && ch.is_uppercase() { - words.push(buf); - buf = String::new(); - } - buf.push_char(ch.to_lowercase()); - } - words.push(buf); - } - words.connect("_") - } - - let s = token::get_ident(ident); - - if !is_snake_case(ident) { - cx.span_lint(NonSnakeCaseFunctions, span, - format!("{} `{}` should have a snake case name such as `{}`", - sort, s, to_snake_case(s.get())).as_slice()); - } -} - -fn check_item_non_uppercase_statics(cx: &Context, it: &ast::Item) { - match it.node { - // only check static constants - ast::ItemStatic(_, ast::MutImmutable, _) => { - let s = token::get_ident(it.ident); - // check for lowercase letters rather than non-uppercase - // ones (some scripts don't have a concept of - // upper/lowercase) - if s.get().chars().any(|c| c.is_lowercase()) { - cx.span_lint(NonUppercaseStatics, it.span, - format!("static constant `{}` should have an uppercase name \ - such as `{}`", s.get(), - s.get().chars().map(|c| c.to_uppercase()) - .collect::().as_slice()).as_slice()); - } - } - _ => {} - } -} - -fn check_pat_non_uppercase_statics(cx: &Context, p: &ast::Pat) { - // Lint for constants that look like binding identifiers (#7526) - match (&p.node, cx.tcx.def_map.borrow().find(&p.id)) { - (&ast::PatIdent(_, ref path, _), Some(&def::DefStatic(_, false))) => { - // last identifier alone is right choice for this lint. - let ident = path.segments.last().unwrap().identifier; - let s = token::get_ident(ident); - if s.get().chars().any(|c| c.is_lowercase()) { - cx.span_lint(NonUppercasePatternStatics, path.span, - format!("static constant in pattern `{}` should have an uppercase \ - name such as `{}`", s.get(), - s.get().chars().map(|c| c.to_uppercase()) - .collect::().as_slice()).as_slice()); - } - } - _ => {} - } -} - -fn check_pat_uppercase_variable(cx: &Context, p: &ast::Pat) { - match &p.node { - &ast::PatIdent(_, ref path, _) => { - match cx.tcx.def_map.borrow().find(&p.id) { - Some(&def::DefLocal(_, _)) | Some(&def::DefBinding(_, _)) | - Some(&def::DefArg(_, _)) => { - // last identifier alone is right choice for this lint. - let ident = path.segments.last().unwrap().identifier; - let s = token::get_ident(ident); - if s.get().len() > 0 && s.get().char_at(0).is_uppercase() { - cx.span_lint( - UppercaseVariables, - path.span, - "variable names should start with a lowercase character"); - } - } - _ => {} - } - } - _ => {} - } -} - -fn check_struct_uppercase_variable(cx: &Context, s: &ast::StructDef) { - for sf in s.fields.iter() { - match sf.node { - ast::StructField_ { kind: ast::NamedField(ident, _), .. } => { - let s = token::get_ident(ident); - if s.get().char_at(0).is_uppercase() { - cx.span_lint( - UppercaseVariables, - sf.span, - "structure field names should start with a lowercase character"); - } - } - _ => {} - } - } -} - -fn check_unnecessary_parens_core(cx: &Context, value: &ast::Expr, msg: &str) { - match value.node { - ast::ExprParen(_) => { - cx.span_lint(UnnecessaryParens, value.span, - format!("unnecessary parentheses around {}", - msg).as_slice()) - } - _ => {} - } -} - -fn check_unnecessary_parens_expr(cx: &Context, e: &ast::Expr) { - let (value, msg) = match e.node { - ast::ExprIf(cond, _, _) => (cond, "`if` condition"), - ast::ExprWhile(cond, _) => (cond, "`while` condition"), - ast::ExprMatch(head, _) => (head, "`match` head expression"), - ast::ExprRet(Some(value)) => (value, "`return` value"), - ast::ExprAssign(_, value) => (value, "assigned value"), - ast::ExprAssignOp(_, _, value) => (value, "assigned value"), - _ => return - }; - check_unnecessary_parens_core(cx, &*value, msg); -} - -fn check_unnecessary_parens_stmt(cx: &Context, s: &ast::Stmt) { - let (value, msg) = match s.node { - ast::StmtDecl(decl, _) => match decl.node { - ast::DeclLocal(local) => match local.init { - Some(value) => (value, "assigned value"), - None => return - }, - _ => return - }, - _ => return - }; - check_unnecessary_parens_core(cx, &*value, msg); -} - -fn check_unused_unsafe(cx: &Context, e: &ast::Expr) { - match e.node { - // Don't warn about generated blocks, that'll just pollute the output. - ast::ExprBlock(ref blk) => { - if blk.rules == ast::UnsafeBlock(ast::UserProvided) && - !cx.tcx.used_unsafe.borrow().contains(&blk.id) { - cx.span_lint(UnusedUnsafe, blk.span, - "unnecessary `unsafe` block"); - } - } - _ => () - } -} - -fn check_unsafe_block(cx: &Context, e: &ast::Expr) { - match e.node { - // Don't warn about generated blocks, that'll just pollute the output. - ast::ExprBlock(ref blk) if blk.rules == ast::UnsafeBlock(ast::UserProvided) => { - cx.span_lint(UnsafeBlock, blk.span, "usage of an `unsafe` block"); - } - _ => () - } -} - -fn check_unused_mut_pat(cx: &Context, pats: &[Gc]) { - // collect all mutable pattern and group their NodeIDs by their Identifier to - // avoid false warnings in match arms with multiple patterns - let mut mutables = HashMap::new(); - for &p in pats.iter() { - pat_util::pat_bindings(&cx.tcx.def_map, &*p, |mode, id, _, path| { - match mode { - ast::BindByValue(ast::MutMutable) => { - if path.segments.len() != 1 { - cx.tcx.sess.span_bug(p.span, - "mutable binding that doesn't consist \ - of exactly one segment"); - } - let ident = path.segments.get(0).identifier; - if !token::get_ident(ident).get().starts_with("_") { - mutables.insert_or_update_with(ident.name as uint, vec!(id), |_, old| { - old.push(id); - }); - } - } - _ => { - } - } - }); - } - - let used_mutables = cx.tcx.used_mut_nodes.borrow(); - for (_, v) in mutables.iter() { - if !v.iter().any(|e| used_mutables.contains(e)) { - cx.span_lint(UnusedMut, cx.tcx.map.span(*v.get(0)), - "variable does not need to be mutable"); - } - } -} - -enum Allocation { - VectorAllocation, - BoxAllocation -} - -fn check_unnecessary_allocation(cx: &Context, e: &ast::Expr) { - // Warn if string and vector literals with sigils, or boxing expressions, - // are immediately borrowed. - let allocation = match e.node { - ast::ExprVstore(e2, ast::ExprVstoreUniq) => { - match e2.node { - ast::ExprLit(lit) if ast_util::lit_is_str(lit) => { - VectorAllocation - } - ast::ExprVec(..) => VectorAllocation, - _ => return - } - } - ast::ExprUnary(ast::UnUniq, _) | - ast::ExprUnary(ast::UnBox, _) => BoxAllocation, - - _ => return - }; - - let report = |msg| { - cx.span_lint(UnnecessaryAllocation, e.span, msg); - }; - - match cx.tcx.adjustments.borrow().find(&e.id) { - Some(adjustment) => { - match *adjustment { - ty::AutoDerefRef(ty::AutoDerefRef { autoref, .. }) => { - match (allocation, autoref) { - (VectorAllocation, Some(ty::AutoBorrowVec(..))) => { - report("unnecessary allocation, the sigil can be \ - removed"); - } - (BoxAllocation, - Some(ty::AutoPtr(_, ast::MutImmutable))) => { - report("unnecessary allocation, use & instead"); - } - (BoxAllocation, - Some(ty::AutoPtr(_, ast::MutMutable))) => { - report("unnecessary allocation, use &mut \ - instead"); - } - _ => () - } - } - _ => {} - } - } - - _ => () - } -} - -fn check_missing_doc_attrs(cx: &Context, - id: Option, - attrs: &[ast::Attribute], - sp: Span, - desc: &'static str) { - // If we're building a test harness, then warning about - // documentation is probably not really relevant right now. - if cx.tcx.sess.opts.test { return } - - // `#[doc(hidden)]` disables missing_doc check. - if cx.is_doc_hidden { return } - - // Only check publicly-visible items, using the result from the privacy pass. It's an option so - // the crate root can also use this function (it doesn't have a NodeId). - match id { - Some(ref id) if !cx.exported_items.contains(id) => return, - _ => () - } - - let has_doc = attrs.iter().any(|a| { - match a.node.value.node { - ast::MetaNameValue(ref name, _) if name.equiv(&("doc")) => true, - _ => false - } - }); - if !has_doc { - cx.span_lint(MissingDoc, - sp, - format!("missing documentation for {}", - desc).as_slice()); - } -} - -fn check_missing_doc_item(cx: &Context, it: &ast::Item) { - let desc = match it.node { - ast::ItemFn(..) => "a function", - ast::ItemMod(..) => "a module", - ast::ItemEnum(..) => "an enum", - ast::ItemStruct(..) => "a struct", - ast::ItemTrait(..) => "a trait", - _ => return - }; - check_missing_doc_attrs(cx, - Some(it.id), - it.attrs.as_slice(), - it.span, - desc); -} - #[deriving(PartialEq)] enum MethodContext { TraitDefaultImpl, @@ -1596,19 +687,6 @@ enum MethodContext { PlainImpl } -fn check_missing_doc_method(cx: &Context, m: &ast::Method) { - // If the method is an impl for a trait, don't doc. - if method_context(cx, m) == TraitImpl { return; } - - // Otherwise, doc according to privacy. This will also check - // doc for default methods defined on traits. - check_missing_doc_attrs(cx, - Some(m.id), - m.attrs.as_slice(), - m.span, - "a method"); -} - fn method_context(cx: &Context, m: &ast::Method) -> MethodContext { let did = ast::DefId { krate: ast::LOCAL_CRATE, @@ -1631,129 +709,32 @@ fn method_context(cx: &Context, m: &ast::Method) -> MethodContext { } } -fn check_missing_doc_ty_method(cx: &Context, tm: &ast::TypeMethod) { - check_missing_doc_attrs(cx, - Some(tm.id), - tm.attrs.as_slice(), - tm.span, - "a type method"); -} +impl<'a> AstConv for Context<'a>{ + fn tcx<'a>(&'a self) -> &'a ty::ctxt { self.tcx } -fn check_missing_doc_struct_field(cx: &Context, sf: &ast::StructField) { - match sf.node.kind { - ast::NamedField(_, vis) if vis == ast::Public => - check_missing_doc_attrs(cx, - Some(cx.cur_struct_def_id), - sf.node.attrs.as_slice(), - sf.span, - "a struct field"), - _ => {} + fn get_item_ty(&self, id: ast::DefId) -> ty::ty_param_bounds_and_ty { + ty::lookup_item_type(self.tcx, id) } -} - -fn check_missing_doc_variant(cx: &Context, v: &ast::Variant) { - check_missing_doc_attrs(cx, - Some(v.node.id), - v.node.attrs.as_slice(), - v.span, - "a variant"); -} - -/// Checks for use of items with #[deprecated], #[experimental] and -/// #[unstable] (or none of them) attributes. -fn check_stability(cx: &Context, e: &ast::Expr) { - let tcx = cx.tcx; - - let id = match e.node { - ast::ExprPath(..) | ast::ExprStruct(..) => { - match cx.tcx.def_map.borrow().find(&e.id) { - Some(&def) => def.def_id(), - None => return - } - } - ast::ExprMethodCall(..) => { - let method_call = typeck::MethodCall::expr(e.id); - match tcx.method_map.borrow().find(&method_call) { - Some(method) => { - match method.origin { - typeck::MethodStatic(def_id) => { - // If this implements a trait method, get def_id - // of the method inside trait definition. - // Otherwise, use the current def_id (which refers - // to the method inside impl). - ty::trait_method_of_method(cx.tcx, def_id) - .unwrap_or(def_id) - } - typeck::MethodParam(typeck::MethodParam { - trait_id: trait_id, - method_num: index, - .. - }) - | typeck::MethodObject(typeck::MethodObject { - trait_id: trait_id, - method_num: index, - .. - }) => ty::trait_method(cx.tcx, trait_id, index).def_id - } - } - None => return - } - } - _ => return - }; - - // stability attributes are promises made across crates; do not - // check anything for crate-local usage. - if ast_util::is_local(id) { return } - - let stability = tcx.stability.borrow_mut().lookup(&tcx.sess.cstore, id); - - let (lint, label) = match stability { - // no stability attributes == Unstable - None => (Unstable, "unmarked"), - Some(attr::Stability { level: attr::Unstable, .. }) => - (Unstable, "unstable"), - Some(attr::Stability { level: attr::Experimental, .. }) => - (Experimental, "experimental"), - Some(attr::Stability { level: attr::Deprecated, .. }) => - (Deprecated, "deprecated"), - _ => return - }; - let msg = match stability { - Some(attr::Stability { text: Some(ref s), .. }) => { - format!("use of {} item: {}", label, *s) - } - _ => format!("use of {} item", label) - }; - - cx.span_lint(lint, e.span, msg.as_slice()); -} + fn get_trait_def(&self, id: ast::DefId) -> Rc { + ty::lookup_trait_def(self.tcx, id) + } -fn check_enum_variant_sizes(cx: &mut Context, it: &ast::Item) { - match it.node { - ast::ItemEnum(..) => { - match cx.cur.find(&(VariantSizeDifference as uint)) { - Some(&(lvl, src)) if lvl != Allow => { - cx.node_levels.insert((it.id, VariantSizeDifference), (lvl, src)); - }, - _ => { } - } - }, - _ => { } + fn ty_infer(&self, _span: Span) -> ty::t { + infer::new_infer_ctxt(self.tcx).next_ty_var() } } impl<'a> Visitor<()> for Context<'a> { fn visit_item(&mut self, it: &ast::Item, _: ()) { self.with_lint_attrs(it.attrs.as_slice(), |cx| { - check_enum_variant_sizes(cx, it); - check_item_ctypes(cx, it); - check_item_non_camel_case_types(cx, it); - check_item_non_uppercase_statics(cx, it); - check_heap_item(cx, it); - check_missing_doc_item(cx, it); - check_raw_ptr_deriving(cx, it); + builtin::check_enum_variant_sizes(cx, it); + builtin::check_item_ctypes(cx, it); + builtin::check_item_non_camel_case_types(cx, it); + builtin::check_item_non_uppercase_statics(cx, it); + builtin::check_heap_item(cx, it); + builtin::check_missing_doc_item(cx, it); + builtin::check_raw_ptr_deriving(cx, it); cx.visit_ids(|v| v.visit_item(it, ())); @@ -1776,8 +757,8 @@ impl<'a> Visitor<()> for Context<'a> { } fn visit_pat(&mut self, p: &ast::Pat, _: ()) { - check_pat_non_uppercase_statics(self, p); - check_pat_uppercase_variable(self, p); + builtin::check_pat_non_uppercase_statics(self, p); + builtin::check_pat_uppercase_variable(self, p); visit::walk_pat(self, p, ()); } @@ -1795,36 +776,36 @@ impl<'a> Visitor<()> for Context<'a> { }, ast::ExprMatch(_, ref arms) => { for a in arms.iter() { - check_unused_mut_pat(self, a.pats.as_slice()); + builtin::check_unused_mut_pat(self, a.pats.as_slice()); } }, _ => () }; - check_while_true_expr(self, e); - check_stability(self, e); - check_unnecessary_parens_expr(self, e); - check_unused_unsafe(self, e); - check_unsafe_block(self, e); - check_unnecessary_allocation(self, e); - check_heap_expr(self, e); + builtin::check_while_true_expr(self, e); + builtin::check_stability(self, e); + builtin::check_unnecessary_parens_expr(self, e); + builtin::check_unused_unsafe(self, e); + builtin::check_unsafe_block(self, e); + builtin::check_unnecessary_allocation(self, e); + builtin::check_heap_expr(self, e); - check_type_limits(self, e); - check_unused_casts(self, e); + builtin::check_type_limits(self, e); + builtin::check_unused_casts(self, e); visit::walk_expr(self, e, ()); } fn visit_stmt(&mut self, s: &ast::Stmt, _: ()) { - check_path_statement(self, s); - check_unused_result(self, s); - check_unnecessary_parens_stmt(self, s); + builtin::check_path_statement(self, s); + builtin::check_unused_result(self, s); + builtin::check_unnecessary_parens_stmt(self, s); match s.node { ast::StmtDecl(d, _) => { match d.node { ast::DeclLocal(l) => { - check_unused_mut_pat(self, &[l.pat]); + builtin::check_unused_mut_pat(self, &[l.pat]); }, _ => {} } @@ -1842,17 +823,19 @@ impl<'a> Visitor<()> for Context<'a> { }; for a in decl.inputs.iter(){ - check_unused_mut_pat(self, &[a.pat]); + builtin::check_unused_mut_pat(self, &[a.pat]); } match *fk { visit::FkMethod(ident, _, m) => { self.with_lint_attrs(m.attrs.as_slice(), |cx| { - check_missing_doc_method(cx, m); + builtin::check_missing_doc_method(cx, m); match method_context(cx, m) { - PlainImpl => check_snake_case(cx, "method", ident, span), - TraitDefaultImpl => check_snake_case(cx, "trait method", ident, span), + PlainImpl + => builtin::check_snake_case(cx, "method", ident, span), + TraitDefaultImpl + => builtin::check_snake_case(cx, "trait method", ident, span), _ => (), } @@ -1863,7 +846,7 @@ impl<'a> Visitor<()> for Context<'a> { }) }, visit::FkItemFn(ident, _, _, _) => { - check_snake_case(self, "function", ident, span); + builtin::check_snake_case(self, "function", ident, span); recurse(self); } _ => recurse(self), @@ -1872,8 +855,8 @@ impl<'a> Visitor<()> for Context<'a> { fn visit_ty_method(&mut self, t: &ast::TypeMethod, _: ()) { self.with_lint_attrs(t.attrs.as_slice(), |cx| { - check_missing_doc_ty_method(cx, t); - check_snake_case(cx, "trait method", t.ident, t.span); + builtin::check_missing_doc_ty_method(cx, t); + builtin::check_snake_case(cx, "trait method", t.ident, t.span); visit::walk_ty_method(cx, t, ()); }) @@ -1885,7 +868,7 @@ impl<'a> Visitor<()> for Context<'a> { _: &ast::Generics, id: ast::NodeId, _: ()) { - check_struct_uppercase_variable(self, s); + builtin::check_struct_uppercase_variable(self, s); let old_id = self.cur_struct_def_id; self.cur_struct_def_id = id; @@ -1895,7 +878,7 @@ impl<'a> Visitor<()> for Context<'a> { fn visit_struct_field(&mut self, s: &ast::StructField, _: ()) { self.with_lint_attrs(s.node.attrs.as_slice(), |cx| { - check_missing_doc_struct_field(cx, s); + builtin::check_missing_doc_struct_field(cx, s); visit::walk_struct_field(cx, s, ()); }) @@ -1903,7 +886,7 @@ impl<'a> Visitor<()> for Context<'a> { fn visit_variant(&mut self, v: &ast::Variant, g: &ast::Generics, _: ()) { self.with_lint_attrs(v.node.attrs.as_slice(), |cx| { - check_missing_doc_variant(cx, v); + builtin::check_missing_doc_variant(cx, v); visit::walk_variant(cx, v, g, ()); }) @@ -1913,7 +896,7 @@ impl<'a> Visitor<()> for Context<'a> { fn visit_ty(&mut self, _t: &ast::Ty, _: ()) {} fn visit_attribute(&mut self, attr: &ast::Attribute, _: ()) { - check_unused_attribute(self, attr); + builtin::check_unused_attribute(self, attr); } } @@ -1965,11 +948,11 @@ pub fn check_crate(tcx: &ty::ctxt, // since the root module isn't visited as an item (because it isn't an item), warn for it // here. - check_missing_doc_attrs(cx, - None, - krate.attrs.as_slice(), - krate.span, - "crate"); + builtin::check_missing_doc_attrs(cx, + None, + krate.attrs.as_slice(), + krate.span, + "crate"); visit::walk_crate(cx, krate, ()); });