+use matches::matches;
use rustc::hir;
use rustc::lint::*;
-use rustc::middle::const_val::ConstVal;
+use rustc::{declare_lint, lint_array};
+use if_chain::if_chain;
use rustc::ty::{self, Ty};
use rustc::hir::def::Def;
-use rustc::ty::subst::Substs;
-use rustc_const_eval::ConstContext;
use std::borrow::Cow;
use std::fmt;
use std::iter;
use syntax::ast;
-use syntax::codemap::Span;
-use utils::{get_trait_def_id, implements_trait, in_external_macro, in_macro, is_copy, is_self, is_self_ty,
- iter_input_pats, last_path_segment, match_def_path, match_path, match_qpath, match_trait_method,
- match_type, method_chain_args, return_ty, same_tys, single_segment_path, snippet, span_lint,
- span_lint_and_sugg, span_lint_and_then, span_note_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth};
-use utils::paths;
-use utils::sugg;
-use utils::const_to_u64;
+use syntax::codemap::{Span, BytePos};
+use crate::utils::{get_arg_name, get_trait_def_id, implements_trait, in_external_macro, in_macro, is_copy, is_expn_of, is_self,
+ is_self_ty, iter_input_pats, last_path_segment, match_def_path, match_path, match_qpath, match_trait_method,
+ match_type, method_chain_args, match_var, return_ty, remove_blocks, same_tys, single_segment_path, snippet,
+ span_lint, span_lint_and_sugg, span_lint_and_then, span_note_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth, SpanlessEq};
+use crate::utils::paths;
+use crate::utils::sugg;
+use crate::consts::{constant, Constant};
#[derive(Clone)]
pub struct Pass;
/// ```rust
/// x.unwrap()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OPTION_UNWRAP_USED,
- Allow,
+ restriction,
"using `Option.unwrap()`, which should at least get a better message using `expect()`"
}
/// ```rust
/// x.unwrap()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub RESULT_UNWRAP_USED,
- Allow,
+ restriction,
"using `Result.unwrap()`, which might be better handled"
}
/// fn add(&self, other: &X) -> X { .. }
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub SHOULD_IMPLEMENT_TRAIT,
- Warn,
+ style,
"defining a method that should be implementing a std trait"
}
/// fn as_str(self) -> &str { .. }
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub WRONG_SELF_CONVENTION,
- Warn,
+ style,
"defining a method named with an established prefix (like \"into_\") that takes \
`self` with the wrong convention"
}
/// pub fn as_str(self) -> &str { .. }
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub WRONG_PUB_SELF_CONVENTION,
- Allow,
+ restriction,
"defining a public method named with an established prefix (like \"into_\") that takes \
`self` with the wrong convention"
}
/// **Why is this bad?** Because you usually call `expect()` on the `Result`
/// directly to get a better error message.
///
-/// **Known problems:** None.
+/// **Known problems:** The error type needs to implement `Debug`
///
/// **Example:**
/// ```rust
/// x.ok().expect("why did I do this again?")
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OK_EXPECT,
- Warn,
+ style,
"using `ok().expect()`, which gives worse error messages than \
calling `expect` directly on the Result"
}
/// **Why is this bad?** Readability, this can be written more concisely as
/// `_.map_or(_, _)`.
///
-/// **Known problems:** None.
+/// **Known problems:** The order of the arguments is not in execution order
///
/// **Example:**
/// ```rust
/// x.map(|a| a + 1).unwrap_or(0)
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OPTION_MAP_UNWRAP_OR,
- Allow,
+ pedantic,
"using `Option.map(f).unwrap_or(a)`, which is more succinctly expressed as \
`map_or(a, f)`"
}
/// **Why is this bad?** Readability, this can be written more concisely as
/// `_.map_or_else(_, _)`.
///
-/// **Known problems:** None.
+/// **Known problems:** The order of the arguments is not in execution order.
///
/// **Example:**
/// ```rust
/// x.map(|a| a + 1).unwrap_or_else(some_function)
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OPTION_MAP_UNWRAP_OR_ELSE,
- Allow,
+ pedantic,
"using `Option.map(f).unwrap_or_else(g)`, which is more succinctly expressed as \
`map_or_else(g, f)`"
}
/// ```rust
/// x.map(|a| a + 1).unwrap_or_else(some_function)
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub RESULT_MAP_UNWRAP_OR_ELSE,
- Allow,
+ pedantic,
"using `Result.map(f).unwrap_or_else(g)`, which is more succinctly expressed as \
`.ok().map_or_else(g, f)`"
}
/// **Why is this bad?** Readability, this can be written more concisely as
/// `_.and_then(_)`.
///
-/// **Known problems:** None.
+/// **Known problems:** The order of the arguments is not in execution order.
///
/// **Example:**
/// ```rust
/// opt.map_or(None, |a| a + 1)
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OPTION_MAP_OR_NONE,
- Warn,
+ style,
"using `Option.map_or(None, f)`, which is more succinctly expressed as \
`and_then(f)`"
}
/// ```rust
/// iter.filter(|x| x == 0).next()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub FILTER_NEXT,
- Warn,
+ complexity,
"using `filter(p).next()`, which is more succinctly expressed as `.find(p)`"
}
/// ```rust
/// iter.filter(|x| x == 0).map(|x| x * 2)
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub FILTER_MAP,
- Allow,
+ pedantic,
"using combinations of `filter`, `map`, `filter_map` and `flat_map` which can \
usually be written as a single method call"
}
/// ```rust
/// iter.find(|x| x == 0).is_some()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub SEARCH_IS_SOME,
- Warn,
+ complexity,
"using an iterator search followed by `is_some()`, which is more succinctly \
expressed as a call to `any()`"
}
/// ```rust
/// name.chars().next() == Some('_')
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub CHARS_NEXT_CMP,
- Warn,
+ complexity,
"using `.chars().next()` to check if a string starts with a char"
}
/// ```rust
/// foo.unwrap_or_default()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub OR_FUN_CALL,
- Warn,
+ perf,
"using any `*or` method with a function call, which suggests `*or_else`"
}
+/// **What it does:** Checks for calls to `.expect(&format!(...))`, `.expect(foo(..))`,
+/// etc., and suggests to use `unwrap_or_else` instead
+///
+/// **Why is this bad?** The function will always be called.
+///
+/// **Known problems:** If the function has side-effects, not calling it will
+/// change the semantic of the program, but you shouldn't rely on that anyway.
+///
+/// **Example:**
+/// ```rust
+/// foo.expect(&format("Err {}: {}", err_code, err_msg))
+/// ```
+/// or
+/// ```rust
+/// foo.expect(format("Err {}: {}", err_code, err_msg).as_str())
+/// ```
+/// this can instead be written:
+/// ```rust
+/// foo.unwrap_or_else(|_| panic!("Err {}: {}", err_code, err_msg))
+/// ```
+/// or
+/// ```rust
+/// foo.unwrap_or_else(|_| panic!(format("Err {}: {}", err_code, err_msg).as_str()))
+/// ```
+declare_clippy_lint! {
+ pub EXPECT_FUN_CALL,
+ perf,
+ "using any `expect` method with a function call"
+}
+
/// **What it does:** Checks for usage of `.clone()` on a `Copy` type.
///
/// **Why is this bad?** The only reason `Copy` types implement `Clone` is for
/// ```rust
/// 42u64.clone()
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub CLONE_ON_COPY,
- Warn,
+ complexity,
"using `clone` on a `Copy` type"
}
/// **What it does:** Checks for usage of `.clone()` on a ref-counted pointer,
-/// (Rc, Arc, rc::Weak, or sync::Weak), and suggests calling Clone on
-/// the corresponding trait instead.
+/// (`Rc`, `Arc`, `rc::Weak`, or `sync::Weak`), and suggests calling Clone via unified
+/// function syntax instead (e.g. `Rc::clone(foo)`).
///
/// **Why is this bad?**: Calling '.clone()' on an Rc, Arc, or Weak
/// can obscure the fact that only the pointer is being cloned, not the underlying
/// ```rust
/// x.clone()
/// ```
-declare_restriction_lint! {
+declare_clippy_lint! {
pub CLONE_ON_REF_PTR,
+ restriction,
"using 'clone' on a ref-counted pointer"
}
/// println!("{:p} {:p}",*y, z); // prints out the same pointer
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub CLONE_DOUBLE_REF,
- Warn,
+ correctness,
"using `clone` on `&&T`"
}
/// }
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub NEW_RET_NO_SELF,
- Warn,
+ style,
"not returning `Self` in a `new` method"
}
///
/// **Example:**
/// `_.split("x")` could be `_.split('x')
-declare_lint! {
+declare_clippy_lint! {
pub SINGLE_CHAR_PATTERN,
- Warn,
+ perf,
"using a single-character str where a char could be used, e.g. \
`_.split(\"x\")`"
}
/// call_some_ffi_func(c_str.as_ptr());
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub TEMPORARY_CSTRING_AS_PTR,
- Warn,
+ correctness,
"getting the inner pointer of a temporary `CString`"
}
/// let bad_vec = some_vec.get(3);
/// let bad_slice = &some_vec[..].get(3);
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub ITER_NTH,
- Warn,
+ perf,
"using `.iter().nth()` on a standard library type with O(1) element access"
}
/// let bad_vec = some_vec.iter().nth(3);
/// let bad_slice = &some_vec[..].iter().nth(3);
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub ITER_SKIP_NEXT,
- Warn,
+ style,
"using `.skip(x).next()` on an iterator"
}
/// let last = some_vec[3];
/// some_vec[0] = 1;
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub GET_UNWRAP,
- Warn,
+ style,
"using `.get().unwrap()` or `.get_mut().unwrap()` when using `[]` would work instead"
}
/// s.push_str(abc);
/// s.push_str(&def));
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub STRING_EXTEND_CHARS,
- Warn,
+ style,
"using `x.extend(s.chars())` where s is a `&str` or `String`"
}
/// let s = [1,2,3,4,5];
/// let s2 : Vec<isize> = s.to_vec();
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub ITER_CLONED_COLLECT,
- Warn,
+ style,
"using `.cloned().collect()` on slice to create a `Vec`"
}
/// ```rust
/// name.chars().last() == Some('_') || name.chars().next_back() == Some('-')
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub CHARS_LAST_CMP,
- Warn,
+ style,
"using `.chars().last()` or `.chars().next_back()` to check if a string ends with a char"
}
/// let x: &[i32] = &[1,2,3,4,5];
/// do_stuff(x);
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub USELESS_ASREF,
- Warn,
+ complexity,
"using `as_ref` where the types before and after the call are the same"
}
+
+/// **What it does:** Checks for using `fold` when a more succinct alternative exists.
+/// Specifically, this checks for `fold`s which could be replaced by `any`, `all`,
+/// `sum` or `product`.
+///
+/// **Why is this bad?** Readability.
+///
+/// **Known problems:** None.
+///
+/// **Example:**
+/// ```rust
+/// let _ = (0..3).fold(false, |acc, x| acc || x > 2);
+/// ```
+/// This could be written as:
+/// ```rust
+/// let _ = (0..3).any(|x| x > 2);
+/// ```
+declare_clippy_lint! {
+ pub UNNECESSARY_FOLD,
+ style,
+ "using `fold` when a more succinct alternative exists"
+}
+
impl LintPass for Pass {
fn get_lints(&self) -> LintArray {
lint_array!(
RESULT_MAP_UNWRAP_OR_ELSE,
OPTION_MAP_OR_NONE,
OR_FUN_CALL,
+ EXPECT_FUN_CALL,
CHARS_NEXT_CMP,
CHARS_LAST_CMP,
CLONE_ON_COPY,
GET_UNWRAP,
STRING_EXTEND_CHARS,
ITER_CLONED_COLLECT,
- USELESS_ASREF
+ USELESS_ASREF,
+ UNNECESSARY_FOLD
)
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
- #[allow(unused_attributes)]
- // ^ required because `cyclomatic_complexity` attribute shows up as unused
- #[cyclomatic_complexity = "30"]
+ #[allow(cyclomatic_complexity)]
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
if in_macro(expr.span) {
return;
}
match expr.node {
- hir::ExprMethodCall(ref method_call, _, ref args) => {
+ hir::ExprKind::MethodCall(ref method_call, ref method_span, ref args) => {
// Chain calls
// GET_UNWRAP needs to be checked before general `UNWRAP` lints
if let Some(arglists) = method_chain_args(expr, &["get", "unwrap"]) {
lint_asref(cx, expr, "as_ref", arglists[0]);
} else if let Some(arglists) = method_chain_args(expr, &["as_mut"]) {
lint_asref(cx, expr, "as_mut", arglists[0]);
+ } else if let Some(arglists) = method_chain_args(expr, &["fold"]) {
+ lint_unnecessary_fold(cx, expr, arglists[0]);
}
- lint_or_fun_call(cx, expr, &method_call.name.as_str(), args);
+ lint_or_fun_call(cx, expr, *method_span, &method_call.ident.as_str(), args);
+ lint_expect_fun_call(cx, expr, *method_span, &method_call.ident.as_str(), args);
let self_ty = cx.tables.expr_ty_adjusted(&args[0]);
- if args.len() == 1 && method_call.name == "clone" {
+ if args.len() == 1 && method_call.ident.name == "clone" {
lint_clone_on_copy(cx, expr, &args[0], self_ty);
lint_clone_on_ref_ptr(cx, expr, &args[0]);
}
match self_ty.sty {
- ty::TyRef(_, ty) if ty.ty.sty == ty::TyStr => for &(method, pos) in &PATTERN_METHODS {
- if method_call.name == method && args.len() > pos {
+ ty::TyRef(_, ty, _) if ty.sty == ty::TyStr => for &(method, pos) in &PATTERN_METHODS {
+ if method_call.ident.name == method && args.len() > pos {
lint_single_char_pattern(cx, expr, &args[pos]);
}
},
_ => (),
}
},
- hir::ExprBinary(op, ref lhs, ref rhs) if op.node == hir::BiEq || op.node == hir::BiNe => {
+ hir::ExprKind::Binary(op, ref lhs, ref rhs) if op.node == hir::BinOpKind::Eq || op.node == hir::BinOpKind::Ne => {
let mut info = BinaryExprInfo {
- expr: expr,
+ expr,
chain: lhs,
other: rhs,
- eq: op.node == hir::BiEq,
+ eq: op.node == hir::BinOpKind::Eq,
};
lint_binary_expr_with_method_call(cx, &mut info);
},
if in_external_macro(cx, implitem.span) {
return;
}
- let name = implitem.name;
+ let name = implitem.ident.name;
let parent = cx.tcx.hir.get_parent(implitem.id);
let item = cx.tcx.hir.expect_item(parent);
if_chain! {
if let hir::ImplItemKind::Method(ref sig, id) = implitem.node;
if let Some(first_arg_ty) = sig.decl.inputs.get(0);
if let Some(first_arg) = iter_input_pats(&sig.decl, cx.tcx.hir.body(id)).next();
- if let hir::ItemImpl(_, _, _, _, None, ref self_ty, _) = item.node;
+ if let hir::ItemKind::Impl(_, _, _, _, None, ref self_ty, _) = item.node;
then {
if cx.access_levels.is_exported(implitem.id) {
// check missing trait implementations
for &(method_name, n_args, self_kind, out_type, trait_name) in &TRAIT_METHODS {
if name == method_name &&
sig.decl.inputs.len() == n_args &&
- out_type.matches(&sig.decl.output) &&
- self_kind.matches(first_arg_ty, first_arg, self_ty, false, &implitem.generics) {
+ out_type.matches(cx, &sig.decl.output) &&
+ self_kind.matches(cx, first_arg_ty, first_arg, self_ty, false, &implitem.generics) {
span_lint(cx, SHOULD_IMPLEMENT_TRAIT, implitem.span, &format!(
"defining a method called `{}` on this type; consider implementing \
the `{}` trait or choosing a less ambiguous name", name, trait_name));
if conv.check(&name.as_str());
if !self_kinds
.iter()
- .any(|k| k.matches(first_arg_ty, first_arg, self_ty, is_copy, &implitem.generics));
+ .any(|k| k.matches(cx, first_arg_ty, first_arg, self_ty, is_copy, &implitem.generics));
then {
- let lint = if item.vis == hir::Visibility::Public {
+ let lint = if item.vis.node.is_pub() {
WRONG_PUB_SELF_CONVENTION
} else {
WRONG_SELF_CONVENTION
}
/// Checks for the `OR_FUN_CALL` lint.
-fn lint_or_fun_call(cx: &LateContext, expr: &hir::Expr, name: &str, args: &[hir::Expr]) {
+fn lint_or_fun_call(cx: &LateContext, expr: &hir::Expr, method_span: Span, name: &str, args: &[hir::Expr]) {
/// Check for `unwrap_or(T::new())` or `unwrap_or(T::default())`.
fn check_unwrap_or_default(
cx: &LateContext,
}
if name == "unwrap_or" {
- if let hir::ExprPath(ref qpath) = fun.node {
- let path = &*last_path_segment(qpath).name.as_str();
+ if let hir::ExprKind::Path(ref qpath) = fun.node {
+ let path = &*last_path_segment(qpath).ident.as_str();
if ["default", "new"].contains(&path) {
let arg_ty = cx.tables.expr_ty(arg);
}
/// Check for `*or(foo())`.
+ #[allow(too_many_arguments)]
fn check_general_case(
cx: &LateContext,
name: &str,
+ method_span: Span,
fun_span: Span,
self_expr: &hir::Expr,
arg: &hir::Expr,
(false, false) => format!("|| {}", snippet(cx, arg.span, "..")).into(),
(false, true) => snippet(cx, fun_span, ".."),
};
-
+ let span_replace_word = method_span.with_hi(span.hi());
span_lint_and_sugg(
cx,
OR_FUN_CALL,
- span,
+ span_replace_word,
&format!("use of `{}` followed by a function call", name),
"try this",
- format!("{}.{}_{}({})", snippet(cx, self_expr.span, "_"), name, suffix, sugg),
+ format!("{}_{}({})", name, suffix, sugg),
);
}
if args.len() == 2 {
match args[1].node {
- hir::ExprCall(ref fun, ref or_args) => {
+ hir::ExprKind::Call(ref fun, ref or_args) => {
let or_has_args = !or_args.is_empty();
if !check_unwrap_or_default(cx, name, fun, &args[0], &args[1], or_has_args, expr.span) {
- check_general_case(cx, name, fun.span, &args[0], &args[1], or_has_args, expr.span);
+ check_general_case(cx, name, method_span, fun.span, &args[0], &args[1], or_has_args, expr.span);
}
},
- hir::ExprMethodCall(_, span, ref or_args) => {
- check_general_case(cx, name, span, &args[0], &args[1], !or_args.is_empty(), expr.span)
+ hir::ExprKind::MethodCall(_, span, ref or_args) => {
+ check_general_case(cx, name, method_span, span, &args[0], &args[1], !or_args.is_empty(), expr.span)
},
_ => {},
}
}
}
+/// Checks for the `EXPECT_FUN_CALL` lint.
+fn lint_expect_fun_call(cx: &LateContext, expr: &hir::Expr, method_span: Span, name: &str, args: &[hir::Expr]) {
+ fn extract_format_args(arg: &hir::Expr) -> Option<&hir::HirVec<hir::Expr>> {
+ if let hir::ExprKind::AddrOf(_, ref addr_of) = arg.node {
+ if let hir::ExprKind::Call(ref inner_fun, ref inner_args) = addr_of.node {
+ if is_expn_of(inner_fun.span, "format").is_some() && inner_args.len() == 1 {
+ if let hir::ExprKind::Call(_, ref format_args) = inner_args[0].node {
+ return Some(format_args);
+ }
+ }
+ }
+ }
+
+ None
+ }
+
+ fn generate_format_arg_snippet(cx: &LateContext, a: &hir::Expr) -> String {
+ if let hir::ExprKind::AddrOf(_, ref format_arg) = a.node {
+ if let hir::ExprKind::Match(ref format_arg_expr, _, _) = format_arg.node {
+ if let hir::ExprKind::Tup(ref format_arg_expr_tup) = format_arg_expr.node {
+ return snippet(cx, format_arg_expr_tup[0].span, "..").into_owned();
+ }
+ }
+ };
+
+ snippet(cx, a.span, "..").into_owned()
+ }
+
+ fn check_general_case(
+ cx: &LateContext,
+ name: &str,
+ method_span: Span,
+ self_expr: &hir::Expr,
+ arg: &hir::Expr,
+ span: Span,
+ ) {
+ if name != "expect" {
+ return;
+ }
+
+ let self_type = cx.tables.expr_ty(self_expr);
+ let known_types = &[&paths::OPTION, &paths::RESULT];
+
+ // if not a known type, return early
+ if known_types.iter().all(|&k| !match_type(cx, self_type, k)) {
+ return;
+ }
+
+ // don't lint for constant values
+ let owner_def = cx.tcx.hir.get_parent_did(arg.id);
+ let promotable = cx.tcx.rvalue_promotable_map(owner_def).contains(&arg.hir_id.local_id);
+ if promotable {
+ return;
+ }
+
+ let closure = if match_type(cx, self_type, &paths::OPTION) { "||" } else { "|_|" };
+ let span_replace_word = method_span.with_hi(span.hi());
+
+ if let Some(format_args) = extract_format_args(arg) {
+ let args_len = format_args.len();
+ let args: Vec<String> = format_args
+ .into_iter()
+ .take(args_len - 1)
+ .map(|a| generate_format_arg_snippet(cx, a))
+ .collect();
+
+ let sugg = args.join(", ");
+
+ span_lint_and_sugg(
+ cx,
+ EXPECT_FUN_CALL,
+ span_replace_word,
+ &format!("use of `{}` followed by a function call", name),
+ "try this",
+ format!("unwrap_or_else({} panic!({}))", closure, sugg),
+ );
+
+ return;
+ }
+
+ let sugg: Cow<_> = snippet(cx, arg.span, "..");
+
+ span_lint_and_sugg(
+ cx,
+ EXPECT_FUN_CALL,
+ span_replace_word,
+ &format!("use of `{}` followed by a function call", name),
+ "try this",
+ format!("unwrap_or_else({} panic!({}))", closure, sugg),
+ );
+ }
+
+ if args.len() == 2 {
+ match args[1].node {
+ hir::ExprKind::Lit(_) => {},
+ _ => check_general_case(cx, name, method_span, &args[0], &args[1], expr.span),
+ }
+ }
+}
+
/// Checks for the `CLONE_ON_COPY` lint.
fn lint_clone_on_copy(cx: &LateContext, expr: &hir::Expr, arg: &hir::Expr, arg_ty: Ty) {
let ty = cx.tables.expr_ty(expr);
- if let ty::TyRef(_, ty::TypeAndMut { ty: inner, .. }) = arg_ty.sty {
- if let ty::TyRef(_, ty::TypeAndMut { ty: innermost, .. }) = inner.sty {
+ if let ty::TyRef(_, inner, _) = arg_ty.sty {
+ if let ty::TyRef(_, innermost, _) = inner.sty {
span_lint_and_then(
cx,
CLONE_DOUBLE_REF,
|db| if let Some(snip) = sugg::Sugg::hir_opt(cx, arg) {
let mut ty = innermost;
let mut n = 0;
- while let ty::TyRef(_, ty::TypeAndMut { ty: inner, .. }) = ty.sty {
+ while let ty::TyRef(_, inner, _) = ty.sty {
ty = inner;
n += 1;
}
match cx.tcx.hir.get(parent) {
hir::map::NodeExpr(parent) => match parent.node {
// &*x is a nop, &x.clone() is not
- hir::ExprAddrOf(..) |
+ hir::ExprKind::AddrOf(..) |
// (*x).func() is useless, x.clone().func() can work in case func borrows mutably
- hir::ExprMethodCall(..) => return,
+ hir::ExprKind::MethodCall(..) => return,
_ => {},
}
hir::map::NodeStmt(stmt) => {
- if let hir::StmtDecl(ref decl, _) = stmt.node {
- if let hir::DeclLocal(ref loc) = decl.node {
+ if let hir::StmtKind::Decl(ref decl, _) = stmt.node {
+ if let hir::DeclKind::Local(ref loc) = decl.node {
if let hir::PatKind::Ref(..) = loc.pat.node {
// let ref y = *x borrows x, let ref y = x.clone() does not
return;
}
fn lint_clone_on_ref_ptr(cx: &LateContext, expr: &hir::Expr, arg: &hir::Expr) {
- let (obj_ty, _) = walk_ptrs_ty_depth(cx.tables.expr_ty(arg));
+ let obj_ty = walk_ptrs_ty(cx.tables.expr_ty(arg));
if let ty::TyAdt(_, subst) = obj_ty.sty {
let caller_type = if match_type(cx, obj_ty, &paths::RC) {
let arg = &args[1];
if let Some(arglists) = method_chain_args(arg, &["chars"]) {
let target = &arglists[0][0];
- let (self_ty, _) = walk_ptrs_ty_depth(cx.tables.expr_ty(target));
+ let self_ty = walk_ptrs_ty(cx.tables.expr_ty(target));
let ref_str = if self_ty.sty == ty::TyStr {
""
} else if match_type(cx, self_ty, &paths::STRING) {
}
fn lint_extend(cx: &LateContext, expr: &hir::Expr, args: &[hir::Expr]) {
- let (obj_ty, _) = walk_ptrs_ty_depth(cx.tables.expr_ty(&args[0]));
+ let obj_ty = walk_ptrs_ty(cx.tables.expr_ty(&args[0]));
if match_type(cx, obj_ty, &paths::STRING) {
lint_string_extend(cx, expr, args);
}
fn lint_cstring_as_ptr(cx: &LateContext, expr: &hir::Expr, new: &hir::Expr, unwrap: &hir::Expr) {
if_chain! {
- if let hir::ExprCall(ref fun, ref args) = new.node;
+ if let hir::ExprKind::Call(ref fun, ref args) = new.node;
if args.len() == 1;
- if let hir::ExprPath(ref path) = fun.node;
+ if let hir::ExprKind::Path(ref path) = fun.node;
if let Def::Method(did) = cx.tables.qpath_def(path, fun.hir_id);
if match_def_path(cx.tcx, did, &paths::CSTRING_NEW);
then {
}
}
+fn lint_unnecessary_fold(cx: &LateContext, expr: &hir::Expr, fold_args: &[hir::Expr]) {
+ // Check that this is a call to Iterator::fold rather than just some function called fold
+ if !match_trait_method(cx, expr, &paths::ITERATOR) {
+ return;
+ }
+
+ assert!(fold_args.len() == 3,
+ "Expected fold_args to have three entries - the receiver, the initial value and the closure");
+
+ fn check_fold_with_op(
+ cx: &LateContext,
+ fold_args: &[hir::Expr],
+ op: hir::BinOpKind,
+ replacement_method_name: &str,
+ replacement_has_args: bool) {
+
+ if_chain! {
+ // Extract the body of the closure passed to fold
+ if let hir::ExprKind::Closure(_, _, body_id, _, _) = fold_args[2].node;
+ let closure_body = cx.tcx.hir.body(body_id);
+ let closure_expr = remove_blocks(&closure_body.value);
+
+ // Check if the closure body is of the form `acc <op> some_expr(x)`
+ if let hir::ExprKind::Binary(ref bin_op, ref left_expr, ref right_expr) = closure_expr.node;
+ if bin_op.node == op;
+
+ // Extract the names of the two arguments to the closure
+ if let Some(first_arg_ident) = get_arg_name(&closure_body.arguments[0].pat);
+ if let Some(second_arg_ident) = get_arg_name(&closure_body.arguments[1].pat);
+
+ if match_var(&*left_expr, first_arg_ident);
+ if replacement_has_args || match_var(&*right_expr, second_arg_ident);
+
+ then {
+ // Span containing `.fold(...)`
+ let next_point = cx.sess().codemap().next_point(fold_args[0].span);
+ let fold_span = next_point.with_hi(fold_args[2].span.hi() + BytePos(1));
+
+ let sugg = if replacement_has_args {
+ format!(
+ ".{replacement}(|{s}| {r})",
+ replacement = replacement_method_name,
+ s = second_arg_ident,
+ r = snippet(cx, right_expr.span, "EXPR"),
+ )
+ } else {
+ format!(
+ ".{replacement}()",
+ replacement = replacement_method_name,
+ )
+ };
+
+ span_lint_and_sugg(
+ cx,
+ UNNECESSARY_FOLD,
+ fold_span,
+ // TODO #2371 don't suggest e.g. .any(|x| f(x)) if we can suggest .any(f)
+ "this `.fold` can be written more succinctly using another method",
+ "try",
+ sugg,
+ );
+ }
+ }
+ }
+
+ // Check if the first argument to .fold is a suitable literal
+ match fold_args[1].node {
+ hir::ExprKind::Lit(ref lit) => {
+ match lit.node {
+ ast::LitKind::Bool(false) => check_fold_with_op(
+ cx, fold_args, hir::BinOpKind::Or, "any", true
+ ),
+ ast::LitKind::Bool(true) => check_fold_with_op(
+ cx, fold_args, hir::BinOpKind::And, "all", true
+ ),
+ ast::LitKind::Int(0, _) => check_fold_with_op(
+ cx, fold_args, hir::BinOpKind::Add, "sum", false
+ ),
+ ast::LitKind::Int(1, _) => check_fold_with_op(
+ cx, fold_args, hir::BinOpKind::Mul, "product", false
+ ),
+ _ => return
+ }
+ }
+ _ => return
+ };
+}
+
fn lint_iter_nth(cx: &LateContext, expr: &hir::Expr, iter_args: &[hir::Expr], is_mut: bool) {
let mut_str = if is_mut { "_mut" } else { "" };
let caller_type = if derefs_to_slice(cx, &iter_args[0], cx.tables.expr_ty(&iter_args[0])).is_some() {
ty::TySlice(_) => true,
ty::TyAdt(def, _) if def.is_box() => may_slice(cx, ty.boxed_ty()),
ty::TyAdt(..) => match_type(cx, ty, &paths::VEC),
- ty::TyArray(_, size) => const_to_u64(size) < 32,
- ty::TyRef(_, ty::TypeAndMut { ty: inner, .. }) => may_slice(cx, inner),
+ ty::TyArray(_, size) => size.assert_usize(cx.tcx).expect("array length") < 32,
+ ty::TyRef(_, inner, _) => may_slice(cx, inner),
_ => false,
}
}
- if let hir::ExprMethodCall(ref path, _, ref args) = expr.node {
- if path.name == "iter" && may_slice(cx, cx.tables.expr_ty(&args[0])) {
+ if let hir::ExprKind::MethodCall(ref path, _, ref args) = expr.node {
+ if path.ident.name == "iter" && may_slice(cx, cx.tables.expr_ty(&args[0])) {
sugg::Sugg::hir_opt(cx, &args[0]).map(|sugg| sugg.addr())
} else {
None
match ty.sty {
ty::TySlice(_) => sugg::Sugg::hir_opt(cx, expr),
ty::TyAdt(def, _) if def.is_box() && may_slice(cx, ty.boxed_ty()) => sugg::Sugg::hir_opt(cx, expr),
- ty::TyRef(_, ty::TypeAndMut { ty: inner, .. }) => if may_slice(cx, inner) {
+ ty::TyRef(_, inner, _) => if may_slice(cx, inner) {
sugg::Sugg::hir_opt(cx, expr)
} else {
None
/// lint use of `unwrap()` for `Option`s and `Result`s
fn lint_unwrap(cx: &LateContext, expr: &hir::Expr, unwrap_args: &[hir::Expr]) {
- let (obj_ty, _) = walk_ptrs_ty_depth(cx.tables.expr_ty(&unwrap_args[0]));
+ let obj_ty = walk_ptrs_ty(cx.tables.expr_ty(&unwrap_args[0]));
let mess = if match_type(cx, obj_ty, &paths::OPTION) {
Some((OPTION_UNWRAP_USED, "an Option", "None"))
fn lint_map_or_none<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr, map_or_args: &'tcx [hir::Expr]) {
if match_type(cx, cx.tables.expr_ty(&map_or_args[0]), &paths::OPTION) {
// check if the first non-self argument to map_or() is None
- let map_or_arg_is_none = if let hir::Expr_::ExprPath(ref qpath) = map_or_args[1].node {
+ let map_or_arg_is_none = if let hir::ExprKind::Path(ref qpath) = map_or_args[1].node {
match_qpath(qpath, &paths::OPTION_NONE)
} else {
false
) -> bool {
if_chain! {
if let Some(args) = method_chain_args(info.chain, chain_methods);
- if let hir::ExprCall(ref fun, ref arg_char) = info.other.node;
+ if let hir::ExprKind::Call(ref fun, ref arg_char) = info.other.node;
if arg_char.len() == 1;
- if let hir::ExprPath(ref qpath) = fun.node;
+ if let hir::ExprKind::Path(ref qpath) = fun.node;
if let Some(segment) = single_segment_path(qpath);
- if segment.name == "Some";
+ if segment.ident.name == "Some";
then {
let self_ty = walk_ptrs_ty(cx.tables.expr_ty_adjusted(&args[0][0]));
) -> bool {
if_chain! {
if let Some(args) = method_chain_args(info.chain, chain_methods);
- if let hir::ExprLit(ref lit) = info.other.node;
+ if let hir::ExprKind::Lit(ref lit) = info.other.node;
if let ast::LitKind::Char(c) = lit.node;
then {
span_lint_and_sugg(
/// lint for length-1 `str`s for methods in `PATTERN_METHODS`
fn lint_single_char_pattern<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr, arg: &'tcx hir::Expr) {
- let parent_item = cx.tcx.hir.get_parent(arg.id);
- let parent_def_id = cx.tcx.hir.local_def_id(parent_item);
- let substs = Substs::identity_for_item(cx.tcx, parent_def_id);
- if let Ok(&ty::Const {
- val: ConstVal::Str(r),
- ..
- }) = ConstContext::new(cx.tcx, cx.param_env.and(substs), cx.tables).eval(arg)
- {
+ if let Some((Constant::Str(r), _)) = constant(cx, cx.tables, arg) {
if r.len() == 1 {
- let hint = snippet(cx, expr.span, "..").replace(&format!("\"{}\"", r), &format!("'{}'", r));
+ let c = r.chars().next().unwrap();
+ let snip = snippet(cx, expr.span, "..");
+ let hint = snip.replace(
+ &format!("\"{}\"", c.escape_default()),
+ &format!("'{}'", c.escape_default()));
span_lint_and_then(
cx,
SINGLE_CHAR_PATTERN,
impl SelfKind {
fn matches(
self,
+ cx: &LateContext,
ty: &hir::Ty,
arg: &hir::Arg,
self_ty: &hir::Ty,
// `Self`, `&mut Self`,
// and `Box<Self>`, including the equivalent types with `Foo`.
- let is_actually_self = |ty| is_self_ty(ty) || ty == self_ty;
+ let is_actually_self = |ty| is_self_ty(ty) || SpanlessEq::new(cx).eq_ty(ty, self_ty);
if is_self(arg) {
match self {
SelfKind::Value => is_actually_self(ty),
return true;
}
match ty.node {
- hir::TyRptr(_, ref mt_ty) => {
+ hir::TyKind::Rptr(_, ref mt_ty) => {
let mutability_match = if self == SelfKind::Ref {
mt_ty.mutbl == hir::MutImmutable
} else {
}
}
- fn description(&self) -> &'static str {
- match *self {
+ fn description(self) -> &'static str {
+ match self {
SelfKind::Value => "self by value",
SelfKind::Ref => "self by reference",
SelfKind::RefMut => "self by mutable reference",
fn is_as_ref_or_mut_trait(ty: &hir::Ty, self_ty: &hir::Ty, generics: &hir::Generics, name: &[&str]) -> bool {
single_segment_ty(ty).map_or(false, |seg| {
- generics.ty_params().any(|param| {
- param.name == seg.name && param.bounds.iter().any(|bound| {
- if let hir::TyParamBound::TraitTyParamBound(ref ptr, ..) = *bound {
- let path = &ptr.trait_ref.path;
- match_path(path, name) && path.segments.last().map_or(false, |s| {
- if let Some(ref params) = s.parameters {
- if params.parenthesized {
- false
+ generics.params.iter().any(|param| match param.kind {
+ hir::GenericParamKind::Type { .. } => {
+ param.name.ident().name == seg.ident.name && param.bounds.iter().any(|bound| {
+ if let hir::GenericBound::Trait(ref ptr, ..) = *bound {
+ let path = &ptr.trait_ref.path;
+ match_path(path, name) && path.segments.last().map_or(false, |s| {
+ if let Some(ref params) = s.args {
+ if params.parenthesized {
+ false
+ } else {
+ // FIXME(flip1995): messy, improve if there is a better option
+ // in the compiler
+ let types: Vec<_> = params.args.iter().filter_map(|arg| match arg {
+ hir::GenericArg::Type(ty) => Some(ty),
+ _ => None,
+ }).collect();
+ types.len() == 1
+ && (is_self_ty(&types[0]) || is_ty(&*types[0], self_ty))
+ }
} else {
- params.types.len() == 1
- && (is_self_ty(¶ms.types[0]) || is_ty(&*params.types[0], self_ty))
+ false
}
- } else {
- false
- }
- })
- } else {
- false
- }
- })
+ })
+ } else {
+ false
+ }
+ })
+ },
+ _ => false,
})
})
}
fn is_ty(ty: &hir::Ty, self_ty: &hir::Ty) -> bool {
match (&ty.node, &self_ty.node) {
(
- &hir::TyPath(hir::QPath::Resolved(_, ref ty_path)),
- &hir::TyPath(hir::QPath::Resolved(_, ref self_ty_path)),
+ &hir::TyKind::Path(hir::QPath::Resolved(_, ref ty_path)),
+ &hir::TyKind::Path(hir::QPath::Resolved(_, ref self_ty_path)),
) => ty_path
.segments
.iter()
- .map(|seg| seg.name)
- .eq(self_ty_path.segments.iter().map(|seg| seg.name)),
+ .map(|seg| seg.ident.name)
+ .eq(self_ty_path.segments.iter().map(|seg| seg.ident.name)),
_ => false,
}
}
fn single_segment_ty(ty: &hir::Ty) -> Option<&hir::PathSegment> {
- if let hir::TyPath(ref path) = ty.node {
+ if let hir::TyKind::Path(ref path) = ty.node {
single_segment_path(path)
} else {
None
}
impl OutType {
- fn matches(&self, ty: &hir::FunctionRetTy) -> bool {
+ fn matches(self, cx: &LateContext, ty: &hir::FunctionRetTy) -> bool {
+ let is_unit = |ty: &hir::Ty| SpanlessEq::new(cx).eq_ty_kind(&ty.node, &hir::TyKind::Tup(vec![].into()));
match (self, ty) {
- (&OutType::Unit, &hir::DefaultReturn(_)) => true,
- (&OutType::Unit, &hir::Return(ref ty)) if ty.node == hir::TyTup(vec![].into()) => true,
- (&OutType::Bool, &hir::Return(ref ty)) if is_bool(ty) => true,
- (&OutType::Any, &hir::Return(ref ty)) if ty.node != hir::TyTup(vec![].into()) => true,
- (&OutType::Ref, &hir::Return(ref ty)) => matches!(ty.node, hir::TyRptr(_, _)),
+ (OutType::Unit, &hir::DefaultReturn(_)) => true,
+ (OutType::Unit, &hir::Return(ref ty)) if is_unit(ty) => true,
+ (OutType::Bool, &hir::Return(ref ty)) if is_bool(ty) => true,
+ (OutType::Any, &hir::Return(ref ty)) if !is_unit(ty) => true,
+ (OutType::Ref, &hir::Return(ref ty)) => matches!(ty.node, hir::TyKind::Rptr(_, _)),
_ => false,
}
}
}
fn is_bool(ty: &hir::Ty) -> bool {
- if let hir::TyPath(ref p) = ty.node {
+ if let hir::TyKind::Path(ref p) = ty.node {
match_qpath(p, &["bool"])
} else {
false
projects / rust.git / blobdiff