Merge remote-tracking branch 'upstream/master' into rustup

[rust.git] / clippy_lints / src / ref_option_ref.rs

diff --git a/clippy_lints/src/ref_option_ref.rs b/clippy_lints/src/ref_option_ref.rs
index 3b9465ec13d7939e7fe79a1c579de69b04bb3c11..a914a77d48b4e3a1f1168925a9098d3896edceea 100644 (file)
--- a/clippy_lints/src/ref_option_ref.rs
+++ b/clippy_lints/src/ref_option_ref.rs
@@ -1,4 +1,4 @@
-use crate::utils::{last_path_segment, match_def_path, paths, snippet, span_lint_and_sugg};
+use crate::utils::{last_path_segment, snippet, span_lint_and_sugg};
 use rustc_hir::{GenericArg, Mutability, Ty, TyKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -12,21 +12,20 @@
     /// **Why is this bad?** Since `&` is Copy, it's useless to have a
     /// reference on `Option<&T>`.
     ///
-    /// **Known problems:** None.
+    /// **Known problems:** It may be irrevelent to use this lint on
+    /// public API code as it will make a breaking change to apply it.
     ///
     /// **Example:**
     ///
     /// ```rust,ignore
-    /// // example code where clippy issues a warning
     /// let x: &Option<&u32> = &Some(&0u32);
     /// ```
     /// Use instead:
     /// ```rust,ignore
-    /// // example code which does not raise clippy warning
     /// let x: Option<&u32> = Some(&0u32);
     /// ```
     pub REF_OPTION_REF,
-    style,
+    pedantic,
     "use `Option<&T>` instead of `&Option<&T>`"
 }
 
@@ -34,12 +33,6 @@
 
 impl<'tcx> LateLintPass<'tcx> for RefOptionRef {
     fn check_ty(&mut self, cx: &LateContext<'tcx>, ty: &'tcx Ty<'tcx>) {
-        self.check_ref_option_ref(cx, ty);
-    }
-}
-
-impl RefOptionRef {
-    fn check_ref_option_ref(&self, cx: &LateContext<'tcx>, ty: &'tcx Ty<'tcx>) {
         if_chain! {
             if let TyKind::Rptr(_, ref mut_ty) = ty.kind;
             if mut_ty.mutbl == Mutability::Not;
@@ -48,7 +41,7 @@ fn check_ref_option_ref(&self, cx: &LateContext<'tcx>, ty: &'tcx Ty<'tcx>) {
             if let Some(res) = last.res;
             if let Some(def_id) = res.opt_def_id();
 
-            if match_def_path(cx, def_id, &paths::OPTION);
+            if cx.tcx.is_diagnostic_item(sym!(option_type), def_id);
             if let Some(ref params) = last_path_segment(qpath).args ;
             if !params.parenthesized;
             if let Some(inner_ty) = params.args.iter().find_map(|arg| match arg {
@@ -62,10 +55,10 @@ fn check_ref_option_ref(&self, cx: &LateContext<'tcx>, ty: &'tcx Ty<'tcx>) {
                     cx,
                     REF_OPTION_REF,
                     ty.span,
-                    "since & implements Copy trait, &Option<&T> can be simplifyied into Option<&T>",
+                    "since `&` implements the `Copy` trait, `&Option<&T>` can be simplified to `Option<&T>`",
                     "try",
                     format!("Option<{}>", &snippet(cx, inner_ty.span, "..")),
-                    Applicability::Unspecified,
+                    Applicability::MaybeIncorrect,
                 );
             }
         }