[do not merge] Relicensing rewrite

CHANGELOG.md

@@ -689,7 +689,6 @@ All notable changes to this project will be documented in this file.
 [`float_cmp`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#float_cmp
 [`float_cmp_const`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#float_cmp_const
 [`fn_to_numeric_cast`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#fn_to_numeric_cast
-[`fn_to_numeric_cast_with_truncation`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#fn_to_numeric_cast_with_truncation
 [`for_kv_map`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#for_kv_map
 [`for_loop_over_option`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#for_loop_over_option
 [`for_loop_over_result`]: https://rust-lang-nursery.github.io/rust-clippy/master/index.html#for_loop_over_result

README.md

@@ -9,7 +9,7 @@ We are currently in the process of discussing Clippy 1.0 via the RFC process in
 
 A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code.
 
-[There are 279 lints included in this crate!](https://rust-lang-nursery.github.io/rust-clippy/master/index.html)
+[There are 278 lints included in this crate!](https://rust-lang-nursery.github.io/rust-clippy/master/index.html)
 
 We have a bunch of lint categories to allow you to choose how much Clippy is supposed to ~~annoy~~ help you:
 

clippy_lints/src/lib.rs

@@ -328,6 +328,7 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
  reg.register_late_lint_pass(box strings::StringAdd);
  reg.register_early_lint_pass(box returns::ReturnPass);
  reg.register_late_lint_pass(box methods::Pass);
+ reg.register_late_lint_pass(box map_clone::Pass);
  reg.register_late_lint_pass(box shadow::Pass);
  reg.register_late_lint_pass(box types::LetPass);
  reg.register_late_lint_pass(box types::UnitCmp);
@@ -346,7 +347,6 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
  reg.register_late_lint_pass(box needless_borrow::NeedlessBorrow);
  reg.register_late_lint_pass(box needless_borrowed_ref::NeedlessBorrowedRef);
  reg.register_late_lint_pass(box no_effect::Pass);
- reg.register_late_lint_pass(box map_clone::Pass);
  reg.register_late_lint_pass(box temporary_assignment::Pass);
  reg.register_late_lint_pass(box transmute::Transmute);
  reg.register_late_lint_pass(
@@ -698,7 +698,6 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
  types::CAST_PTR_ALIGNMENT,
  types::CHAR_LIT_AS_U8,
  types::FN_TO_NUMERIC_CAST,
- types::FN_TO_NUMERIC_CAST_WITH_TRUNCATION,
  types::IMPLICIT_HASHER,
  types::LET_UNIT_VALUE,
  types::OPTION_OPTION,
@@ -921,7 +920,6 @@ pub fn register_plugins(reg: &mut rustc_plugin::Registry<'_>, conf: &Conf) {
  transmute::WRONG_TRANSMUTE,
  types::ABSURD_EXTREME_COMPARISONS,
  types::CAST_PTR_ALIGNMENT,
- types::FN_TO_NUMERIC_CAST_WITH_TRUNCATION,
  types::UNIT_CMP,
  unicode::ZERO_WIDTH_SPACE,
  unused_io_amount::UNUSED_IO_AMOUNT,

clippy_lints/src/map_clone.rs

@@ -1,140 +1,98 @@
+use crate::rustc::hir;
 use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
 use crate::rustc::{declare_tool_lint, lint_array};
+use crate::syntax::source_map::Span;
+use crate::utils::paths;
+use crate::utils::{
+ in_macro, match_trait_method, match_type,
+ remove_blocks, snippet,
+ span_lint_and_sugg,
+};
 use if_chain::if_chain;
-use crate::rustc::hir::*;
-use crate::rustc::ty;
-use crate::syntax::ast;
-use crate::utils::{get_arg_ident, is_adjusted, iter_input_pats, match_qpath, match_trait_method, match_type,
- paths, remove_blocks, snippet, span_help_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth, SpanlessEq};
+use crate::syntax::ast::Ident;
 
-/// **What it does:** Checks for mapping `clone()` over an iterator.
+#[derive(Clone)]
+pub struct Pass;
+
+/// **What it does:** Checks for usage of `iterator.map(|x| x.clone())` and suggests
+/// `iterator.cloned()` instead
 ///
-/// **Why is this bad?** It makes the code less readable than using the
-/// `.cloned()` adapter.
+/// **Why is this bad?** Readability, this can be written more concisely
 ///
-/// **Known problems:** Sometimes `.cloned()` requires stricter trait
-/// bound than `.map(|e| e.clone())` (which works because of the coercion).
-/// See [#498](https://github.com/rust-lang-nursery/rust-clippy/issues/498).
+/// **Known problems:** None.
 ///
 /// **Example:**
+///
+/// ```rust
+/// let x = vec![42, 43];
+/// let y = x.iter();
+/// let z = y.map(|i| *i);
+/// ```
+///
+/// The correct use would be:
+///
 /// ```rust
-/// x.map(|e| e.clone());
+/// let x = vec![42, 43];
+/// let y = x.iter();
+/// let z = y.cloned();
 /// ```
 declare_clippy_lint! {
  pub MAP_CLONE,
  style,
- "using `.map(|x| x.clone())` to clone an iterator or option's contents"
+ "using `iterator.map(|x| x.clone())`, or dereferencing closures for `Copy` types"
 }
 
-#[derive(Copy, Clone)]
-pub struct Pass;
+impl LintPass for Pass {
+ fn get_lints(&self) -> LintArray {
+ lint_array!(MAP_CLONE)
+ }
+}
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
- // call to .map()
- if let ExprKind::MethodCall(ref method, _, ref args) = expr.node {
- if method.ident.name == "map" && args.len() == 2 {
- match args[1].node {
- ExprKind::Closure(_, ref decl, closure_eid, _, _) => {
- let body = cx.tcx.hir.body(closure_eid);
- let closure_expr = remove_blocks(&body.value);
- if_chain! {
- // nothing special in the argument, besides reference bindings
- // (e.g. .map(|&x| x) )
- if let Some(first_arg) = iter_input_pats(decl, body).next();
- if let Some(arg_ident) = get_arg_ident(&first_arg.pat);
- // the method is being called on a known type (option or iterator)
- if let Some(type_name) = get_type_name(cx, expr, &args[0]);
- then {
- // We know that body.arguments is not empty at this point
- let ty = cx.tables.pat_ty(&body.arguments[0].pat);
- // look for derefs, for .map(|x| *x)
- if only_derefs(cx, &*closure_expr, arg_ident) &&
- // .cloned() only removes one level of indirection, don't lint on more
- walk_ptrs_ty_depth(cx.tables.pat_ty(&first_arg.pat)).1 == 1
- {
- // the argument is not an &mut T
- if let ty::Ref(_, _, mutbl) = ty.sty {
- if mutbl == MutImmutable {
- span_help_and_lint(cx, MAP_CLONE, expr.span, &format!(
- "you seem to be using .map() to clone the contents of an {}, consider \
- using `.cloned()`", type_name),
- &format!("try\n{}.cloned()", snippet(cx, args[0].span, "..")));
- }
- }
- }
- // explicit clone() calls ( .map(|x| x.clone()) )
- else if let ExprKind::MethodCall(ref clone_call, _, ref clone_args) = closure_expr.node {
- if clone_call.ident.name == "clone" &&
- clone_args.len() == 1 &&
- match_trait_method(cx, closure_expr, &paths::CLONE_TRAIT) &&
- expr_eq_name(cx, &clone_args[0], arg_ident)
- {
- span_help_and_lint(cx, MAP_CLONE, expr.span, &format!(
- "you seem to be using .map() to clone the contents of an {}, consider \
- using `.cloned()`", type_name),
- &format!("try\n{}.cloned()", snippet(cx, args[0].span, "..")));
- }
- }
- }
- }
+ fn check_expr(&mut self, cx: &LateContext<'_, '_>, e: &hir::Expr) {
+ if in_macro(e.span) {
+ return;
+ }
+
+ if_chain! {
+ if let hir::ExprKind::MethodCall(ref method, _, ref args) = e.node;
+ if args.len() == 2;
+ if method.ident.as_str() == "map";
+ let ty = cx.tables.expr_ty(&args[0]);
+ if match_type(cx, ty, &paths::OPTION) || match_trait_method(cx, e, &paths::ITERATOR);
+ if let hir::ExprKind::Closure(_, _, body_id, _, _) = args[1].node;
+ let closure_body = cx.tcx.hir.body(body_id);
+ let closure_expr = remove_blocks(&closure_body.value);
+ then {
+ match closure_body.arguments[0].pat.node {
+ hir::PatKind::Ref(ref inner, _) => if let hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, _, name, None) = inner.node {
+ lint(cx, e.span, args[0].span, name, closure_expr);
  },
- ExprKind::Path(ref path) => if match_qpath(path, &paths::CLONE) {
- let type_name = get_type_name(cx, expr, &args[0]).unwrap_or("_");
- span_help_and_lint(
- cx,
- MAP_CLONE,
- expr.span,
- &format!(
- "you seem to be using .map() to clone the contents of an \
- {}, consider using `.cloned()`",
- type_name
- ),
- &format!("try\n{}.cloned()", snippet(cx, args[0].span, "..")),
- );
+ hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, _, name, None) => match closure_expr.node {
+ hir::ExprKind::Unary(hir::UnOp::UnDeref, ref inner) => lint(cx, e.span, args[0].span, name, inner),
+ hir::ExprKind::MethodCall(ref method, _, ref obj) => if method.ident.as_str() == "clone" && match_trait_method(cx, closure_expr, &paths::CLONE_TRAIT) {
+ lint(cx, e.span, args[0].span, name, &obj[0]);
+ }
+ _ => {},
  },
- _ => (),
+ _ => {},
  }
  }
  }
  }
 }
 
-fn expr_eq_name(cx: &LateContext<'_, '_>, expr: &Expr, id: ast::Ident) -> bool {
- match expr.node {
- ExprKind::Path(QPath::Resolved(None, ref path)) => {
- let arg_segment = [
- PathSegment {
- ident: id,
- args: None,
- infer_types: true,
- },
- ];
- !path.is_global() && SpanlessEq::new(cx).eq_path_segments(&path.segments[..], &arg_segment)
- },
- _ => false,
- }
-}
-
-fn get_type_name(cx: &LateContext<'_, '_>, expr: &Expr, arg: &Expr) -> Option<&'static str> {
- if match_trait_method(cx, expr, &paths::ITERATOR) {
- Some("iterator")
- } else if match_type(cx, walk_ptrs_ty(cx.tables.expr_ty(arg)), &paths::OPTION) {
- Some("Option")
- } else {
- None
- }
-}
-
-fn only_derefs(cx: &LateContext<'_, '_>, expr: &Expr, id: ast::Ident) -> bool {
- match expr.node {
- ExprKind::Unary(UnDeref, ref subexpr) if !is_adjusted(cx, subexpr) => only_derefs(cx, subexpr, id),
- _ => expr_eq_name(cx, expr, id),
- }
-}
-
-impl LintPass for Pass {
- fn get_lints(&self) -> LintArray {
- lint_array!(MAP_CLONE)
+fn lint(cx: &LateContext<'_, '_>, replace: Span, root: Span, name: Ident, path: &hir::Expr) {
+ if let hir::ExprKind::Path(hir::QPath::Resolved(None, ref path)) = path.node {
+ if path.segments.len() == 1 && path.segments[0].ident == name {
+ span_lint_and_sugg(
+ cx,
+ MAP_CLONE,
+ replace,
+ "You are using an explicit closure for cloning elements",
+ "Consider calling the dedicated `cloned` method",
+ format!("{}.cloned()", snippet(cx, root, "..")),
+ )
+ }
  }
 }