use std::borrow::Cow;
use rustc::hir::*;
-use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
use rustc::hir::map::NodeItem;
+use rustc::hir::QPath;
use rustc::lint::*;
use rustc::ty;
-use syntax::ast::{Name, NodeId};
+use syntax::ast::NodeId;
use syntax::codemap::Span;
use syntax_pos::MultiSpan;
-use utils::{get_pat_name, match_qpath, match_type, match_var, paths,
- snippet, snippet_opt, span_lint, span_lint_and_then,
- walk_ptrs_hir_ty};
+use crate::utils::{match_qpath, match_type, paths, snippet_opt, span_lint, span_lint_and_then, walk_ptrs_hir_ty};
+use crate::utils::ptr::get_spans;
/// **What it does:** This lint checks for function arguments of type `&String`
/// or `&Vec` unless the references are mutable. It will also suggest you
/// ```rust
/// fn foo(&Vec<u32>) { .. }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub PTR_ARG,
- Warn,
+ style,
"fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` \
instead, respectively"
}
/// ```rust
/// if x == ptr::null { .. }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub CMP_NULL,
- Warn,
+ style,
"comparing a pointer to a null pointer, suggesting to use `.is_null()` instead."
}
/// ```rust
/// fn foo(&Foo) -> &mut Bar { .. }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub MUT_FROM_REF,
- Warn,
+ correctness,
"fns that create mutable refs from immutable ref args"
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for PointerPass {
fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
- if let ItemFn(ref decl, _, _, _, _, body_id) = item.node {
+ if let ItemFn(ref decl, _, _, body_id) = item.node {
check_fn(cx, decl, item.id, Some(body_id));
}
}
fn check_trait_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx TraitItem) {
if let TraitItemKind::Method(ref sig, ref trait_method) = item.node {
- let body_id = if let TraitMethod::Provided(b) = *trait_method { Some(b) } else { None };
+ let body_id = if let TraitMethod::Provided(b) = *trait_method {
+ Some(b)
+ } else {
+ None
+ };
check_fn(cx, &sig.decl, item.id, body_id);
}
}
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
- if let ExprBinary(ref op, ref l, ref r) = expr.node {
- if (op.node == BiEq || op.node == BiNe) && (is_null_path(l) || is_null_path(r)) {
+ if let ExprKind::Binary(ref op, ref l, ref r) = expr.node {
+ if (op.node == BinOpKind::Eq || op.node == BinOpKind::Ne) && (is_null_path(l) || is_null_path(r)) {
span_lint(
cx,
CMP_NULL,
for (idx, (arg, ty)) in decl.inputs.iter().zip(fn_ty.inputs()).enumerate() {
if let ty::TyRef(
_,
- ty::TypeAndMut {
- ty,
- mutbl: MutImmutable,
- },
+ ty,
+ MutImmutable
) = ty.sty
{
if match_type(cx, ty, &paths::VEC) {
let mut ty_snippet = None;
- if_let_chain!([
- let TyPath(QPath::Resolved(_, ref path)) = walk_ptrs_hir_ty(arg).node,
- let Some(&PathSegment{parameters: Some(ref parameters), ..}) = path.segments.last(),
- parameters.types.len() == 1,
- ], {
- ty_snippet = snippet_opt(cx, parameters.types[0].span);
- });
- if let Ok(spans) = get_spans(cx, opt_body_id, idx, &[("clone", ".to_owned()")]) {
+ if_chain! {
+ if let TyPath(QPath::Resolved(_, ref path)) = walk_ptrs_hir_ty(arg).node;
+ if let Some(&PathSegment{args: Some(ref parameters), ..}) = path.segments.last();
+ then {
+ let types: Vec<_> = parameters.args.iter().filter_map(|arg| match arg {
+ GenericArg::Type(ty) => Some(ty),
+ _ => None,
+ }).collect();
+ if types.len() == 1 {
+ ty_snippet = snippet_opt(cx, types[0].span);
+ }
+ }
+ };
+ if let Some(spans) = get_spans(cx, opt_body_id, idx, &[("clone", ".to_owned()")]) {
span_lint_and_then(
cx,
PTR_ARG,
with non-Vec-based slices.",
|db| {
if let Some(ref snippet) = ty_snippet {
- db.span_suggestion(arg.span,
- "change this to",
- format!("&[{}]", snippet));
+ db.span_suggestion(arg.span, "change this to", format!("&[{}]", snippet));
}
for (clonespan, suggestion) in spans {
- db.span_suggestion(clonespan,
- &snippet_opt(cx, clonespan).map_or("change the call to".into(),
- |x| Cow::Owned(format!("change `{}` to", x))),
- suggestion.into());
+ db.span_suggestion(
+ clonespan,
+ &snippet_opt(cx, clonespan).map_or(
+ "change the call to".into(),
+ |x| Cow::Owned(format!("change `{}` to", x)),
+ ),
+ suggestion.into(),
+ );
}
- }
+ },
);
}
} else if match_type(cx, ty, &paths::STRING) {
- if let Ok(spans) = get_spans(cx, opt_body_id, idx, &[("clone", ".to_string()"), ("as_str", "")]) {
+ if let Some(spans) = get_spans(cx, opt_body_id, idx, &[("clone", ".to_string()"), ("as_str", "")]) {
span_lint_and_then(
cx,
PTR_ARG,
arg.span,
"writing `&String` instead of `&str` involves a new object where a slice will do.",
|db| {
- db.span_suggestion(arg.span,
- "change this to",
- "&str".into());
+ db.span_suggestion(arg.span, "change this to", "&str".into());
for (clonespan, suggestion) in spans {
- db.span_suggestion_short(clonespan,
- &snippet_opt(cx, clonespan).map_or("change the call to".into(),
- |x| Cow::Owned(format!("change `{}` to", x))),
- suggestion.into());
+ db.span_suggestion_short(
+ clonespan,
+ &snippet_opt(cx, clonespan).map_or(
+ "change the call to".into(),
+ |x| Cow::Owned(format!("change `{}` to", x)),
+ ),
+ suggestion.into(),
+ );
}
- }
+ },
);
}
+ } else if match_type(cx, ty, &paths::COW) {
+ if_chain! {
+ if let TyRptr(_, MutTy { ref ty, ..} ) = arg.node;
+ if let TyPath(ref path) = ty.node;
+ if let QPath::Resolved(None, ref pp) = *path;
+ if let [ref bx] = *pp.segments;
+ if let Some(ref params) = bx.args;
+ if !params.parenthesized;
+ if let Some(inner) = params.args.iter().find_map(|arg| match arg {
+ GenericArg::Type(ty) => Some(ty),
+ GenericArg::Lifetime(_) => None,
+ });
+ then {
+ let replacement = snippet_opt(cx, inner.span);
+ if let Some(r) = replacement {
+ span_lint_and_then(
+ cx,
+ PTR_ARG,
+ arg.span,
+ "using a reference to `Cow` is not recommended.",
+ |db| {
+ db.span_suggestion(arg.span, "change this to", "&".to_owned() + &r);
+ },
+ );
+ }
+ }
+ }
}
}
}
}
}
-fn get_spans(cx: &LateContext, opt_body_id: Option<BodyId>, idx: usize, replacements: &'static [(&'static str, &'static str)]) -> Result<Vec<(Span, Cow<'static, str>)>, ()> {
- if let Some(body) = opt_body_id.map(|id| cx.tcx.hir.body(id)) {
- get_binding_name(&body.arguments[idx]).map_or_else(|| Ok(vec![]),
- |name| extract_clone_suggestions(cx, name, replacements, body))
- } else {
- Ok(vec![])
- }
-}
-
-fn extract_clone_suggestions<'a, 'tcx: 'a>(cx: &LateContext<'a, 'tcx>, name: Name, replace: &'static [(&'static str, &'static str)], body: &'tcx Body) -> Result<Vec<(Span, Cow<'static, str>)>, ()> {
- let mut visitor = PtrCloneVisitor {
- cx,
- name,
- replace,
- spans: vec![],
- abort: false,
- };
- visitor.visit_body(body);
- if visitor.abort { Err(()) } else { Ok(visitor.spans) }
-}
-
-struct PtrCloneVisitor<'a, 'tcx: 'a> {
- cx: &'a LateContext<'a, 'tcx>,
- name: Name,
- replace: &'static [(&'static str, &'static str)],
- spans: Vec<(Span, Cow<'static, str>)>,
- abort: bool,
-}
-
-impl<'a, 'tcx: 'a> Visitor<'tcx> for PtrCloneVisitor<'a, 'tcx> {
- fn visit_expr(&mut self, expr: &'tcx Expr) {
- if self.abort { return; }
- if let ExprMethodCall(ref seg, _, ref args) = expr.node {
- if args.len() == 1 && match_var(&args[0], self.name) {
- if seg.name == "capacity" {
- self.abort = true;
- return;
- }
- for &(fn_name, suffix) in self.replace {
- if seg.name == fn_name {
- self.spans.push((expr.span, snippet(self.cx, args[0].span, "_") + suffix));
- return;
- }
- }
- }
- return;
- }
- walk_expr(self, expr);
- }
-
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
- NestedVisitorMap::None
- }
-
-}
-
-fn get_binding_name(arg: &Arg) -> Option<Name> {
- get_pat_name(&arg.pat)
-}
-
fn get_rptr_lm(ty: &Ty) -> Option<(&Lifetime, Mutability, Span)> {
if let Ty_::TyRptr(ref lt, ref m) = ty.node {
Some((lt, m.mutbl, ty.span))
}
fn is_null_path(expr: &Expr) -> bool {
- if let ExprCall(ref pathexp, ref args) = expr.node {
+ if let ExprKind::Call(ref pathexp, ref args) = expr.node {
if args.is_empty() {
- if let ExprPath(ref path) = pathexp.node {
+ if let ExprKind::Path(ref path) = pathexp.node {
return match_qpath(path, &paths::PTR_NULL) || match_qpath(path, &paths::PTR_NULL_MUT);
}
}
projects / rust.git / blobdiff