Add suggestion to missing backticks error

clippy_lints/src/doc.rs

@@ -1,6 +1,6 @@
 use clippy_utils::attrs::is_doc_hidden;
-use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_note};
-use clippy_utils::source::first_line_of_span;
+use clippy_utils::diagnostics::{span_lint, span_lint_and_help, span_lint_and_note, span_lint_and_sugg};
+use clippy_utils::source::{first_line_of_span, snippet_with_applicability};
 use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
 use clippy_utils::{is_entrypoint_fn, is_expn_of, match_panic_def_id, method_chain_args, return_ty};
 use if_chain::if_chain;
@@ -10,7 +10,7 @@ use rustc_ast::token::CommentKind;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::emitter::EmitterWriter;
-use rustc_errors::Handler;
+use rustc_errors::{Applicability, Handler};
 use rustc_hir as hir;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_hir::{AnonConst, Expr, ExprKind, QPath};
@@ -48,7 +48,7 @@ declare_clippy_lint! {
     /// content are not linted.
     ///
     /// In addition, when writing documentation comments, including `[]` brackets
-    /// inside a link text would trip the parser. Therfore, documenting link with
+    /// inside a link text would trip the parser. Therefore, documenting link with
     /// `[`SmallVec<[T; INLINE_CAPACITY]>`]` and then [`SmallVec<[T; INLINE_CAPACITY]>`]: SmallVec
     /// would fail.
     ///
@@ -747,17 +747,22 @@ fn check_word(cx: &LateContext<'_>, word: &str, span: Span) {
         }
     }
 
-    // We assume that mixed-case words are not meant to be put inside bacticks. (Issue #2343)
+    // We assume that mixed-case words are not meant to be put inside backticks. (Issue #2343)
     if has_underscore(word) && has_hyphen(word) {
         return;
     }
 
     if has_underscore(word) || word.contains("::") || is_camel_case(word) {
-        span_lint(
+        let mut applicability = Applicability::MachineApplicable;
+
+        span_lint_and_sugg(
             cx,
             DOC_MARKDOWN,
             span,
-            &format!("you should put `{}` between ticks in the documentation", word),
+            "item in documentation is missing backticks",
+            "try",
+            format!("`{}`", snippet_with_applicability(cx, span, "..", &mut applicability)),
+            applicability,
         );
     }
 }
@@ -796,9 +801,9 @@ impl<'a, 'tcx> Visitor<'tcx> for FindPanicUnwrap<'a, 'tcx> {
 
         // check for `unwrap`
         if let Some(arglists) = method_chain_args(expr, &["unwrap"]) {
-            let reciever_ty = self.typeck_results.expr_ty(&arglists[0][0]).peel_refs();
-            if is_type_diagnostic_item(self.cx, reciever_ty, sym::Option)
-                || is_type_diagnostic_item(self.cx, reciever_ty, sym::Result)
+            let receiver_ty = self.typeck_results.expr_ty(&arglists[0][0]).peel_refs();
+            if is_type_diagnostic_item(self.cx, receiver_ty, sym::Option)
+                || is_type_diagnostic_item(self.cx, receiver_ty, sym::Result)
             {
                 self.panic_span = Some(expr.span);
             }

tests/ui/doc/doc.stderr

@@ -1,160 +1,160 @@
-error: you should put `foo_bar` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:8:9
    |
 LL | /// The foo_bar function does _nothing_. See also foo::bar. (note the dot there)
-   |         ^^^^^^^
+   |         ^^^^^^^ help: try: ``foo_bar``
    |
    = note: `-D clippy::doc-markdown` implied by `-D warnings`
 
-error: you should put `foo::bar` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:8:51
    |
 LL | /// The foo_bar function does _nothing_. See also foo::bar. (note the dot there)
-   |                                                   ^^^^^^^^
+   |                                                   ^^^^^^^^ help: try: ``foo::bar``
 
-error: you should put `Foo::some_fun` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:9:83
    |
 LL | /// Markdown is _weird_. I mean _really weird_. This /_ is ok. So is `_`. But not Foo::some_fun
-   |                                                                                   ^^^^^^^^^^^^^
+   |                                                                                   ^^^^^^^^^^^^^ help: try: ``Foo::some_fun``
 
-error: you should put `a::global:path` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:11:15
    |
 LL | /// Here be ::a::global:path.
-   |               ^^^^^^^^^^^^^^
+   |               ^^^^^^^^^^^^^^ help: try: ``a::global:path``
 
-error: you should put `NotInCodeBlock` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:12:22
    |
 LL | /// That's not code ~NotInCodeBlock~.
-   |                      ^^^^^^^^^^^^^^
+   |                      ^^^^^^^^^^^^^^ help: try: ``NotInCodeBlock``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:13:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:27:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:34:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:48:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:71:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `link_with_underscores` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:75:22
    |
 LL | /// This test has [a link_with_underscores][chunked-example] inside it. See #823.
-   |                      ^^^^^^^^^^^^^^^^^^^^^
+   |                      ^^^^^^^^^^^^^^^^^^^^^ help: try: ``link_with_underscores``
 
-error: you should put `inline_link2` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:78:21
    |
 LL | /// It can also be [inline_link2].
-   |                     ^^^^^^^^^^^^
+   |                     ^^^^^^^^^^^^ help: try: ``inline_link2``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:88:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `CamelCaseThing` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:96:8
    |
 LL | /// ## CamelCaseThing
-   |        ^^^^^^^^^^^^^^
+   |        ^^^^^^^^^^^^^^ help: try: ``CamelCaseThing``
 
-error: you should put `CamelCaseThing` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:99:7
    |
 LL | /// # CamelCaseThing
-   |       ^^^^^^^^^^^^^^
+   |       ^^^^^^^^^^^^^^ help: try: ``CamelCaseThing``
 
-error: you should put `CamelCaseThing` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:101:22
    |
 LL | /// Not a title #897 CamelCaseThing
-   |                      ^^^^^^^^^^^^^^
+   |                      ^^^^^^^^^^^^^^ help: try: ``CamelCaseThing``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:102:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:109:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:122:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `FooBar` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:133:43
    |
 LL | /** E.g., serialization of an empty list: FooBar
-   |                                           ^^^^^^
+   |                                           ^^^^^^ help: try: ``FooBar``
 
-error: you should put `BarQuz` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:138:5
    |
 LL | And BarQuz too.
-   |     ^^^^^^
+   |     ^^^^^^ help: try: ``BarQuz``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:139:1
    |
 LL | be_sure_we_got_to_the_end_of_it
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `FooBar` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:144:43
    |
 LL | /** E.g., serialization of an empty list: FooBar
-   |                                           ^^^^^^
+   |                                           ^^^^^^ help: try: ``FooBar``
 
-error: you should put `BarQuz` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:149:5
    |
 LL | And BarQuz too.
-   |     ^^^^^^
+   |     ^^^^^^ help: try: ``BarQuz``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:150:1
    |
 LL | be_sure_we_got_to_the_end_of_it
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
-error: you should put `be_sure_we_got_to_the_end_of_it` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:161:5
    |
 LL | /// be_sure_we_got_to_the_end_of_it
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: ``be_sure_we_got_to_the_end_of_it``
 
 error: you should put bare URLs between `<`/`>` or make a proper Markdown link
   --> $DIR/doc.rs:188:13
@@ -180,11 +180,11 @@ error: you should put bare URLs between `<`/`>` or make a proper Markdown link
 LL | /// Not ok: http://www.unicode.org/reports/tr9/#Reordering_Resolved_Levels
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: you should put `mycrate::Collection` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/doc.rs:194:22
    |
 LL | /// An iterator over mycrate::Collection's values.
-   |                      ^^^^^^^^^^^^^^^^^^^
+   |                      ^^^^^^^^^^^^^^^^^^^ help: try: ``mycrate::Collection``
 
 error: aborting due to 31 previous errors
 

tests/ui/doc/missing_ticks.fixed

@@ -0,0 +1,9 @@
+// run-rustfix
+#![allow(dead_code)]
+#![warn(clippy::doc_markdown)]
+
+/// `SomeItem`
+fn main() {}
+
+/// `SomeItem`
+fn main1() {}

tests/ui/doc/missing_ticks.rs

@@ -0,0 +1,9 @@
+// run-rustfix
+#![allow(dead_code)]
+#![warn(clippy::doc_markdown)]
+
+/// SomeItem
+fn main() {}
+
+/// `SomeItem`
+fn main1() {}

tests/ui/doc/missing_ticks.stderr

@@ -0,0 +1,10 @@
+error: item in documentation is missing backticks
+  --> $DIR/missing_ticks.rs:5:5
+   |
+LL | /// SomeItem
+   |     ^^^^^^^^ help: try: ``SomeItem``
+   |
+   = note: `-D clippy::doc-markdown` implied by `-D warnings`
+
+error: aborting due to previous error
+

tests/ui/doc/unbalanced_ticks.stderr

@@ -18,11 +18,11 @@ LL | /// This paragraph has `unbalanced_tick marks and should stop_linting.
    |
    = help: a backtick may be missing a pair
 
-error: you should put `should_be` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/unbalanced_ticks.rs:15:32
    |
 LL | /// This paragraph is fine and should_be linted normally.
-   |                                ^^^^^^^^^
+   |                                ^^^^^^^^^ help: try: ``should_be``
 
 error: backticks are unbalanced
   --> $DIR/unbalanced_ticks.rs:17:1
@@ -32,11 +32,11 @@ LL | /// Double unbalanced backtick from ``here to here` should lint.
    |
    = help: a backtick may be missing a pair
 
-error: you should put `not_fine` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/unbalanced_ticks.rs:30:8
    |
 LL | /// ## not_fine
-   |        ^^^^^^^^
+   |        ^^^^^^^^ help: try: ``not_fine``
 
 error: backticks are unbalanced
   --> $DIR/unbalanced_ticks.rs:32:1
@@ -54,11 +54,11 @@ LL | /// - This `item has unbalanced tick marks
    |
    = help: a backtick may be missing a pair
 
-error: you should put `backticks_here` between ticks in the documentation
+error: item in documentation is missing backticks
   --> $DIR/unbalanced_ticks.rs:35:23
    |
 LL | /// - This item needs backticks_here
-   |                       ^^^^^^^^^^^^^^
+   |                       ^^^^^^^^^^^^^^ help: try: ``backticks_here``
 
 error: aborting due to 8 previous errors