]> git.lizzy.rs Git - rust.git/blobdiff - clippy_lints/src/drop_forget_ref.rs
Merge pull request #3465 from flip1995/rustfmt
[rust.git] / clippy_lints / src / drop_forget_ref.rs
index dfa8ddbab6ccaa3027c9d82043788e42ec8f483d..a9741c7a2ddc60abeefd74518cd5a6874171c849 100644 (file)
@@ -1,7 +1,18 @@
-use rustc::lint::*;
-use rustc::ty;
-use rustc::hir::*;
-use utils::{match_def_path, paths, span_note_and_lint, is_copy};
+// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use crate::rustc::hir::*;
+use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use crate::rustc::ty;
+use crate::rustc::{declare_tool_lint, lint_array};
+use crate::utils::{is_copy, match_def_path, opt_def_id, paths, span_note_and_lint};
+use if_chain::if_chain;
 
 /// **What it does:** Checks for calls to `std::mem::drop` with a reference
 /// instead of an owned value.
 /// ```rust
 /// let mut lock_guard = mutex.lock();
 /// std::mem::drop(&lock_guard) // Should have been drop(lock_guard), mutex
-/// still locked
+/// // still locked
 /// operation_that_requires_mutex_to_be_unlocked();
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub DROP_REF,
-    Warn,
+    correctness,
     "calls to `std::mem::drop` with a reference instead of an owned value"
 }
 
@@ -41,9 +52,9 @@
 /// let x = Box::new(1);
 /// std::mem::forget(&x) // Should have been forget(x), x will still be dropped
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub FORGET_REF,
-    Warn,
+    correctness,
     "calls to `std::mem::forget` with a reference instead of an owned value"
 }
 
 ///
 /// **Example:**
 /// ```rust
-/// let x:i32 = 42;   // i32 implements Copy
+/// let x: i32 = 42; // i32 implements Copy
 /// std::mem::drop(x) // A copy of x is passed to the function, leaving the
-/// original unaffected
+///                   // original unaffected
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub DROP_COPY,
-    Warn,
+    correctness,
     "calls to `std::mem::drop` with a value that implements Copy"
 }
 
 ///
 /// **Example:**
 /// ```rust
-/// let x:i32 = 42;     // i32 implements Copy
+/// let x: i32 = 42; // i32 implements Copy
 /// std::mem::forget(x) // A copy of x is passed to the function, leaving the
-/// original unaffected
+///                     // original unaffected
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub FORGET_COPY,
-    Warn,
+    correctness,
     "calls to `std::mem::forget` with a value that implements Copy"
 }
 
 const DROP_REF_SUMMARY: &str = "calls to `std::mem::drop` with a reference instead of an owned value. \
-                               Dropping a reference does nothing.";
+                                Dropping a reference does nothing.";
 const FORGET_REF_SUMMARY: &str = "calls to `std::mem::forget` with a reference instead of an owned value. \
-                                 Forgetting a reference does nothing.";
+                                  Forgetting a reference does nothing.";
 const DROP_COPY_SUMMARY: &str = "calls to `std::mem::drop` with a value that implements Copy. \
-                                Dropping a copy leaves the original intact.";
+                                 Dropping a copy leaves the original intact.";
 const FORGET_COPY_SUMMARY: &str = "calls to `std::mem::forget` with a value that implements Copy. \
-                                  Forgetting a copy leaves the original intact.";
+                                   Forgetting a copy leaves the original intact.";
 
-#[allow(missing_copy_implementations)]
 pub struct Pass;
 
 impl LintPass for Pass {
@@ -115,50 +125,51 @@ fn get_lints(&self) -> LintArray {
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
-        if_let_chain!{[
-            let ExprCall(ref path, ref args) = expr.node,
-            let ExprPath(ref qpath) = path.node,
-            args.len() == 1,
-        ], {
-            let def_id = cx.tables.qpath_def(qpath, path.hir_id).def_id();
-            let lint;
-            let msg;
-            let arg = &args[0];
-            let arg_ty = cx.tables.expr_ty(arg);
+        if_chain! {
+            if let ExprKind::Call(ref path, ref args) = expr.node;
+            if let ExprKind::Path(ref qpath) = path.node;
+            if args.len() == 1;
+            if let Some(def_id) = opt_def_id(cx.tables.qpath_def(qpath, path.hir_id));
+            then {
+                let lint;
+                let msg;
+                let arg = &args[0];
+                let arg_ty = cx.tables.expr_ty(arg);
 
-            if let ty::TyRef(..) = arg_ty.sty {
-                if match_def_path(cx.tcx, def_id, &paths::DROP) {
-                    lint = DROP_REF;
-                    msg = DROP_REF_SUMMARY.to_string();
-                } else if match_def_path(cx.tcx, def_id, &paths::MEM_FORGET) {
-                    lint = FORGET_REF;
-                    msg = FORGET_REF_SUMMARY.to_string();
-                } else {
-                    return;
-                }
-                span_note_and_lint(cx,
-                                   lint,
-                                   expr.span,
-                                   &msg,
-                                   arg.span,
-                                   &format!("argument has type {}", arg_ty));
-            } else if is_copy(cx, arg_ty) {
-                if match_def_path(cx.tcx, def_id, &paths::DROP) {
-                    lint = DROP_COPY;
-                    msg = DROP_COPY_SUMMARY.to_string();
-                } else if match_def_path(cx.tcx, def_id, &paths::MEM_FORGET) {
-                    lint = FORGET_COPY;
-                    msg = FORGET_COPY_SUMMARY.to_string();
-                } else {
-                    return;
+                if let ty::Ref(..) = arg_ty.sty {
+                    if match_def_path(cx.tcx, def_id, &paths::DROP) {
+                        lint = DROP_REF;
+                        msg = DROP_REF_SUMMARY.to_string();
+                    } else if match_def_path(cx.tcx, def_id, &paths::MEM_FORGET) {
+                        lint = FORGET_REF;
+                        msg = FORGET_REF_SUMMARY.to_string();
+                    } else {
+                        return;
+                    }
+                    span_note_and_lint(cx,
+                                       lint,
+                                       expr.span,
+                                       &msg,
+                                       arg.span,
+                                       &format!("argument has type {}", arg_ty));
+                } else if is_copy(cx, arg_ty) {
+                    if match_def_path(cx.tcx, def_id, &paths::DROP) {
+                        lint = DROP_COPY;
+                        msg = DROP_COPY_SUMMARY.to_string();
+                    } else if match_def_path(cx.tcx, def_id, &paths::MEM_FORGET) {
+                        lint = FORGET_COPY;
+                        msg = FORGET_COPY_SUMMARY.to_string();
+                    } else {
+                        return;
+                    }
+                    span_note_and_lint(cx,
+                                       lint,
+                                       expr.span,
+                                       &msg,
+                                       arg.span,
+                                       &format!("argument has type {}", arg_ty));
                 }
-                span_note_and_lint(cx,
-                                   lint,
-                                   expr.span,
-                                   &msg,
-                                   arg.span,
-                                   &format!("argument has type {}", arg_ty));
             }
-        }}
+        }
     }
 }