script:
- python util/update_lints.py -c
- cargo test
+ - bash util/dogfood.sh
if in_macro(cx, info) { return; }
if let ExprIf(ref check, ref then, None) = e.node {
- if let Some(&Expr{ node: ExprIf(ref check_inner, ref content, None), ..}) =
+ if let Some(&Expr{ node: ExprIf(ref check_inner, ref content, None), span: sp, ..}) =
single_stmt_of_block(then) {
+ if e.span.expn_id != sp.expn_id {
+ return;
+ }
+ cx.sess().note(&format!("{:?} -- {:?}", e.span, sp));
span_help_and_lint(cx, COLLAPSIBLE_IF, e.span,
"this if statement can be collapsed",
&format!("try\nif {} && {} {}",
+#![allow(redundant_closure)] // FIXME (#116)
use rustc::lint::*;
use syntax::ast::*;
use syntax::ast_util as ast_util;
#![feature(plugin_registrar, box_syntax)]
#![feature(rustc_private, collections)]
-#![allow(unused_imports)]
+#![allow(unused_imports, unknown_lints)]
#[macro_use]
extern crate syntax;
lint_array!(NEEDLESS_LIFETIMES)
}
- fn check_fn(&mut self, cx: &Context, kind: FnKind, decl: &FnDecl,
- _: &Block, span: Span, _: NodeId) {
- if in_external_macro(cx, span) {
- return;
+ fn check_item(&mut self, cx: &Context, item: &Item) {
+ if let ItemFn(ref decl, _, _, _, ref generics, _) = item.node {
+ check_fn_inner(cx, decl, None, &generics.lifetimes, item.span);
}
- if could_use_elision(kind, decl) {
- span_lint(cx, NEEDLESS_LIFETIMES, span,
- "explicit lifetimes given in parameter types where they could be elided");
+ }
+
+ fn check_impl_item(&mut self, cx: &Context, item: &ImplItem) {
+ if let MethodImplItem(ref sig, _) = item.node {
+ check_fn_inner(cx, &*sig.decl, Some(&sig.explicit_self),
+ &sig.generics.lifetimes, item.span);
+ }
+ }
+
+ fn check_trait_item(&mut self, cx: &Context, item: &TraitItem) {
+ if let MethodTraitItem(ref sig, _) = item.node {
+ check_fn_inner(cx, &*sig.decl, Some(&sig.explicit_self),
+ &sig.generics.lifetimes, item.span);
}
}
}
}
use self::RefLt::*;
-fn could_use_elision(kind: FnKind, func: &FnDecl) -> bool {
+fn check_fn_inner(cx: &Context, decl: &FnDecl, slf: Option<&ExplicitSelf>,
+ named_lts: &[LifetimeDef], span: Span) {
+ if in_external_macro(cx, span) {
+ return;
+ }
+ if could_use_elision(decl, slf, named_lts) {
+ span_lint(cx, NEEDLESS_LIFETIMES, span,
+ "explicit lifetimes given in parameter types where they could be elided");
+ }
+}
+
+fn could_use_elision(func: &FnDecl, slf: Option<&ExplicitSelf>,
+ named_lts: &[LifetimeDef]) -> bool {
// There are two scenarios where elision works:
// * no output references, all input references have different LT
// * output references, exactly one input reference with same LT
+ // All lifetimes must be unnamed, 'static or defined without bounds on the
+ // level of the current item.
+
+ // check named LTs
+ let mut allowed_lts = HashSet::new();
+ for lt in named_lts {
+ if lt.bounds.is_empty() {
+ allowed_lts.insert(Named(lt.lifetime.name));
+ }
+ }
+ allowed_lts.insert(Unnamed);
+ allowed_lts.insert(Static);
// these will collect all the lifetimes for references in arg/return types
let mut input_visitor = RefVisitor(Vec::new());
// extract lifetime in "self" argument for methods (there is a "self" argument
// in func.inputs, but its type is TyInfer)
- if let FnKind::FkMethod(_, sig, _) = kind {
- match sig.explicit_self.node {
+ if let Some(slf) = slf {
+ match slf.node {
SelfRegion(ref opt_lt, _, _) => input_visitor.record(opt_lt),
SelfExplicit(ref ty, _) => walk_ty(&mut input_visitor, ty),
_ => { }
let input_lts = input_visitor.into_vec();
let output_lts = output_visitor.into_vec();
+ // check for lifetimes from higher scopes
+ for lt in input_lts.iter().chain(output_lts.iter()) {
+ if !allowed_lts.contains(lt) {
+ return false;
+ }
+ }
+
// no input lifetimes? easy case!
if input_lts.is_empty() {
return false;
}
/// Number of unique lifetimes in the given vector.
-fn unique_lifetimes(lts: &Vec<RefLt>) -> usize {
+fn unique_lifetimes(lts: &[RefLt]) -> usize {
lts.iter().collect::<HashSet<_>>().len()
}
walk_expr(&mut visitor, body);
// linting condition: we only indexed one variable
if visitor.indexed.len() == 1 {
- let indexed = visitor.indexed.into_iter().next().unwrap();
+ let indexed = visitor.indexed.into_iter().next().expect("Len was nonzero, but no contents found");
if visitor.nonindex {
span_lint(cx, NEEDLESS_RANGE_LOOP, expr.span, &format!(
"the loop variable `{}` is used to index `{}`. Consider using \
/// Recover the essential nodes of a desugared for loop:
/// `for pat in arg { body }` becomes `(pat, arg, body)`.
-fn recover_for_loop<'a>(expr: &'a Expr) -> Option<(&'a Pat, &'a Expr, &'a Expr)> {
+fn recover_for_loop(expr: &Expr) -> Option<(&Pat, &Expr, &Expr)> {
if_let_chain! {
[
let ExprMatch(ref iterexpr, ref arms, _) = expr.node,
let ExprCall(_, ref iterargs) = iterexpr.node,
- iterargs.len() == 1,
- arms.len() == 1 && arms[0].guard.is_none(),
+ iterargs.len() == 1 && arms.len() == 1 && arms[0].guard.is_none(),
let ExprLoop(ref block, _) = arms[0].body.node,
block.stmts.is_empty(),
let Some(ref loopexpr) = block.expr,
}
fn check_fn(&mut self, cx: &Context, _: FnKind, decl: &FnDecl, _: &Block, _: Span, _: NodeId) {
- for ref arg in decl.inputs.iter() {
+ for ref arg in &decl.inputs {
if let PatIdent(BindByRef(_), _, _) = arg.pat.node {
span_lint(cx,
TOPLEVEL_REF_ARG,
}
/// return the base type for references and raw pointers
-pub fn walk_ptrs_ty<'t>(ty: ty::Ty<'t>) -> ty::Ty<'t> {
+pub fn walk_ptrs_ty(ty: ty::Ty) -> ty::Ty {
match ty.sty {
ty::TyRef(_, ref tm) | ty::TyRawPtr(ref tm) => walk_ptrs_ty(tm.ty),
_ => ty
#![plugin(clippy)]
#![deny(needless_lifetimes)]
-
+#![allow(dead_code)]
fn distinct_lifetimes<'a, 'b>(_x: &'a u8, _y: &'b u8, _z: u8) { }
//~^ERROR explicit lifetimes given
type Ref<'r> = &'r u8;
-fn lifetime_param_1<'a>(_x: Ref<'a>, _y: &'a u8) { }
+fn lifetime_param_1<'a>(_x: Ref<'a>, _y: &'a u8) { } // no error, same lifetime on two params
-fn lifetime_param_2<'a, 'b: 'a>(_x: Ref<'a>, _y: &'b u8) { }
+fn lifetime_param_2<'a, 'b>(_x: Ref<'a>, _y: &'b u8) { }
//~^ERROR explicit lifetimes given
+fn lifetime_param_3<'a, 'b: 'a>(_x: Ref<'a>, _y: &'b u8) { } // no error, bounded lifetime
+
struct X {
x: u8,
}
fn self_and_same_in<'s>(&'s self, _x: &'s u8) { } // no error, same lifetimes on two params
}
+struct Foo<'a>(&'a u8);
+
+impl<'a> Foo<'a> {
+ fn self_shared_lifetime(&self, _: &'a u8) {} // no error, lifetime 'a not defined in method
+ fn self_bound_lifetime<'b: 'a>(&self, _: &'b u8) {} // no error, bounds exist
+}
static STATIC: u8 = 1;
fn main() {
- distinct_lifetimes(&1, &2, 3);
- distinct_and_static(&1, &2, &STATIC);
- same_lifetime_on_input(&1, &2);
- only_static_on_input(&1, &2, &STATIC);
- in_and_out(&1, 2);
- multiple_in_and_out_1(&1, &2);
- multiple_in_and_out_2(&1, &2);
- in_static_and_out(&1, &STATIC);
- let _ = deep_reference_1(&1, &2);
- let _ = deep_reference_2(Ok(&1));
- let _ = deep_reference_3(&1, 2);
- lifetime_param_1(&1, &2);
- lifetime_param_2(&1, &2);
-
- let foo = X { x: 1 };
- foo.self_and_out();
- foo.self_and_in_out(&1);
- foo.distinct_self_and_in(&1);
- foo.self_and_same_in(&1);
}
--- /dev/null
+rm -rf target*/*so
+cargo build --lib && cp -R target target_recur && cargo rustc -- -Zextra-plugins=clippy -Ltarget_recur/debug -Dclippy || exit 1
+rm -rf target_recur
+