warn on macro_use attr

cargo dev update lints fixed suggestion, check edition, ran `tests/ui/update-all-references.sh` fixed failing tests with update-references.sh warn on macro_use attr (issue rust-lang#5179) fixed suggestion, check edition, ran `tests/ui/update-all-references.sh` fixed failing tests with update-references.sh update-references.sh for missing-doc-impl.rs use if_chain cargo dev fmt
DevinR528 · Apr 3, 2020 · 53df638 · 53df638
1 parent 7907abe
commit 53df638
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Showing 4 changed files with 51 additions and 35 deletions.
diff --git a/clippy_lints/src/macro_use.rs b/clippy_lints/src/macro_use.rs
@@ -1,7 +1,6 @@
-use crate::utils::{snippet, span_lint_and_sugg};
+use crate::utils::span_lint_and_help;
 use if_chain::if_chain;
 use rustc_ast::ast;
-use rustc_errors::Applicability;
 use rustc_lint::{EarlyContext, EarlyLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::edition::Edition;
@@ -12,21 +11,21 @@ declare_clippy_lint! {
     /// **Why is this bad?** Since the Rust 2018 edition you can import
     /// macro's directly, this is considered idiomatic.
     ///
-    /// **Known problems:** This lint does not generate an auto-applicable suggestion.
+    /// **Known problems:** None.
     ///
     /// **Example:**
     /// ```rust
     /// #[macro_use]
     /// use lazy_static;
     /// ```
-    pub MACRO_USE_IMPORTS,
+    pub MACRO_USE_IMPORT,
     pedantic,
     "#[macro_use] is no longer needed"
 }
 
-declare_lint_pass!(MacroUseImports => [MACRO_USE_IMPORTS]);
+declare_lint_pass!(MacroUseImport => [MACRO_USE_IMPORT]);
 
-impl EarlyLintPass for MacroUseImports {
+impl EarlyLintPass for MacroUseImport {
     fn check_item(&mut self, ecx: &EarlyContext<'_>, item: &ast::Item) {
         if_chain! {
             if ecx.sess.opts.edition == Edition::Edition2018;
@@ -36,17 +35,24 @@ impl EarlyLintPass for MacroUseImports {
                 .iter()
                 .find(|attr| attr.ident().map(|s| s.to_string()) == Some("macro_use".to_string()));
             then {
-                let msg = "`macro_use` attributes are no longer needed in the Rust 2018 edition";
-                let help = format!("use {}::<macro name>", snippet(ecx, use_tree.span, "_"));
-                span_lint_and_sugg(
-                    ecx,
-                    MACRO_USE_IMPORTS,
-                    mac_attr.span,
-                    msg,
-                    "remove the attribute and import the macro directly, try",
-                    help,
-                    Applicability::HasPlaceholders,
-                );
+                let msg = "`macro_use` attribute's are no longer needed in the Rust 2018 edition";
+                    let help = format!(
+                        "remove the attribute and import the macro directly `use {}::<macro name>`",
+                        use_tree
+                            .clone()
+                            .into_inner()
+                            .prefix
+                            .segments
+                            .iter()
+                            .enumerate()
+                            .map(|(i, s)| if i == 0 {
+                                s.ident.to_string()
+                            } else {
+                                format!("::{}", s.ident)
+                            })
+                            .collect::<String>(),
+                    );
+                span_lint_and_help(ecx, MACRO_USE_IMPORT, mac_attr.span, msg, &help);
             }
         }
     }

diff --git a/tests/ui/declare_interior_mutable_const.stderr b/tests/ui/declare_interior_mutable_const.stderr
@@ -45,25 +45,19 @@ error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:44:5
    |
 LL |     const INPUT: T;
-   |     ^^^^^^^^^^^^^-^
-   |                  |
-   |                  consider requiring `T` to be `Copy`
+   |     ^^^^^^^^^^^^^^^
 
 error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:47:5
    |
 LL |     const ASSOC: Self::NonCopyType;
-   |     ^^^^^^^^^^^^^-----------------^
-   |                  |
-   |                  consider requiring `<Self as Trait<T>>::NonCopyType` to be `Copy`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:51:5
    |
 LL |     const AN_INPUT: T = Self::INPUT;
-   |     ^^^^^^^^^^^^^^^^-^^^^^^^^^^^^^^^
-   |                     |
-   |                     consider requiring `T` to be `Copy`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:16:9
@@ -80,9 +74,7 @@ error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:60:5
    |
 LL |     const SELF_2: Self;
-   |     ^^^^^^^^^^^^^^----^
-   |                   |
-   |                   consider requiring `Self` to be `Copy`
+   |     ^^^^^^^^^^^^^^^^^^^
 
 error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:81:5
@@ -94,17 +86,13 @@ error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:84:5
    |
 LL |     const U_SELF: U = U::SELF_2;
-   |     ^^^^^^^^^^^^^^-^^^^^^^^^^^^^
-   |                   |
-   |                   consider requiring `U` to be `Copy`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: a `const` item should never be interior mutable
   --> $DIR/declare_interior_mutable_const.rs:87:5
    |
 LL |     const T_ASSOC: T::NonCopyType = T::ASSOC;
-   |     ^^^^^^^^^^^^^^^--------------^^^^^^^^^^^^
-   |                    |
-   |                    consider requiring `<T as Trait<u32>>::NonCopyType` to be `Copy`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 13 previous errors
 
diff --git a/tests/ui/macro_use_import.rs b/tests/ui/macro_use_import.rs
@@ -0,0 +1,11 @@
+// compile-flags: --edition 2018
+#![warn(clippy::macro_use_import)]
+
+use std::collections::HashMap;
+#[macro_use]
+use std::prelude;
+
+fn main() {
+    let _ = HashMap::<u8, u8>::new();
+    println!();
+}
diff --git a/tests/ui/macro_use_import.stderr b/tests/ui/macro_use_import.stderr
@@ -0,0 +1,11 @@
+error: `macro_use` attribute's are no longer needed in the Rust 2018 edition
+  --> $DIR/macro_use_import.rs:5:1
+   |
+LL | #[macro_use]
+   | ^^^^^^^^^^^^
+   |
+   = note: `-D clippy::macro-use-import` implied by `-D warnings`
+   = help: remove the attribute and import the macro directly `use std::prelude::<macro name>`
+
+error: aborting due to previous error
+