fix wording, remove commented out code, add additonal testcase

Author: Jacherr

clippy_lints/src/doc/doc_comment_double_space_linebreak.rs

@@ -14,10 +14,10 @@ pub fn check(cx: &LateContext<'_>, collected_breaks: &[Span]) {
             cx,
             DOC_COMMENT_DOUBLE_SPACE_LINEBREAK,
             lo_span.to(hi_span),
-            "doc comments should use a back-slash (\\) instead of a double space to indicate a linebreak",
+            "doc comment uses two spaces for a hard line break",
             |diag| {
                 diag.multipart_suggestion(
-                    "replace this double space with a back-slash",
+                    "replace this double space with a backslash",
                     replacements,
                     Applicability::MachineApplicable,
                 );
@@ -38,59 +38,3 @@ fn collect_doc_replacements(cx: &LateContext<'_>, spans: &[Span]) -> Vec<(Span,
         })
         .collect()
 }
-
-/*
-use clippy_utils::diagnostics::span_lint_and_then;
-use rustc_ast::token::CommentKind;
-use rustc_ast::{AttrKind, AttrStyle, Attribute};
-use rustc_errors::Applicability;
-use rustc_lint::LateContext;
-use rustc_span::Span;
-
-use super::DOC_COMMENT_DOUBLE_SPACE_LINEBREAK;
-
-pub fn check(cx: &LateContext<'_>, attrs: &[Attribute]) {
-    let replacements: Vec<_> = collect_doc_replacements(attrs);
-
-    if let Some((&(lo_span, _), &(hi_span, _))) = replacements.first().zip(replacements.last()) {
-        span_lint_and_then(
-            cx,
-            DOC_COMMENT_DOUBLE_SPACE_LINEBREAK,
-            lo_span.to(hi_span),
-            "doc comments should use a back-slash (\\) instead of a double space to indicate a linebreak",
-            |diag| {
-                diag.multipart_suggestion(
-                    "replace this double space with a back-slash",
-                    replacements,
-                    Applicability::MachineApplicable,
-                );
-            },
-        );
-    }
-}
-
-fn collect_doc_replacements(attrs: &[Attribute]) -> Vec<(Span, String)> {
-    attrs
-        .iter()
-        .filter_map(|attr| {
-            if let AttrKind::DocComment(com_kind, sym) = attr.kind
-                && !attr.span.from_expansion()
-                && com_kind == CommentKind::Line
-                && let comment = sym.as_str()
-                && comment.ends_with("  ")
-            {
-                let pre = match attr.style {
-                    AttrStyle::Outer => "///",
-                    AttrStyle::Inner => "//!",
-                };
-
-                let len = comment.len();
-                let new_comment = format!("{pre}{}\\", &comment[..len - 2]);
-                Some((attr.span, new_comment))
-            } else {
-                None
-            }
-        })
-        .collect()
-}
-*/

tests/ui/doc/doc_comment_double_space_linebreak.rs

@@ -83,4 +83,12 @@ fn inline() {}
 /// https://example.com) in a URL.  
 fn url() {}
 
+/// here we mix  
+/// double spaces\
+/// and also  
+/// adding backslash\
+/// to some of them  
+/// to see how that looks
+fn mixed() {}
+
 fn main() {}