Fixed formatting.

Author: ofeeg

clippy_lints/src/methods/mod.rs

@@ -3218,19 +3218,32 @@ declare_clippy_lint! {
 }
 
 declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for initial '/' in an argument to .join on a path.
+    /// Checks for initial `'/'` in an argument to `.join()` on a `Path`.
+    ///
     /// ### Why is this bad?
-    /// .join() calls on paths already attach the '/'.
+    /// `.join()` comments starting with a separator, can replace the entire path.
+    /// If this is intentional, prefer creating a new `Path` instead.
+    ///
+    /// See [`Path::join()`](https://doc.rust-lang.org/std/path/struct.Path.html#method.join)
+    ///
     /// ### Example
     /// ```rust
-    /// // example code where clippy issues a warning
     /// let path = std::path::Path::new("/bin");
-    /// path.join("/sh");
+    /// let res = path.join("/sh");
+    /// assert_eq!(res, PathBuf::from("/sh"));
     /// ```
+    ///
     /// Use instead:
     /// ```rust
-    /// // path.join("sh");
+    /// let path = std::path::Path::new("/bin");
+    ///
+    /// // If this was unintentional, remove the leading separator
+    /// let extend = path.join("sh");
+    /// assert_eq!(extend, PathBuf::from("/bin/sh"));
+    ///
+    /// // If this was intentional, create a new path instead
+    /// let new = Path::new("/sh")
+    /// assert_eq!(new PathBuf::from("/sh"));
     /// ```
     #[clippy::version = "1.70.0"]
     pub PATH_JOIN_CORRECTION,
@@ -3678,7 +3691,7 @@ impl Methods {
                     if let Some(("collect", _, _, span, _)) = method_call(recv) {
                         unnecessary_join::check(cx, expr, recv, join_arg, span);
                     }
-		    else {path_join_correction::check(cx, expr,  join_arg, span);}
+                    else {path_join_correction::check(cx, expr,  join_arg, span);}
                 },
                 ("last", []) | ("skip", [_]) => {
                     if let Some((name2, recv2, args2, _span2, _)) = method_call(recv) {

clippy_lints/src/methods/path_join_correction.rs

@@ -10,21 +10,21 @@ use super::PATH_JOIN_CORRECTION;
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>, join_arg: &'tcx Expr<'tcx>, span: Span) {
     let ty = cx.typeck_results().expr_ty(expr);
     if_chain!(
-    if is_type_diagnostic_item(cx, ty, Path);
-    let applicability = Applicability::MachineApplicable;
-    if let ExprKind::Lit(spanned) = &join_arg.kind;
-    if let LitKind::Str(symbol, _) = spanned.node;
-    if symbol.as_str().starts_with('/') || symbol.as_str().starts_with('\\');
+     if is_type_diagnostic_item(cx, ty, Path);
+     let applicability = Applicability::MachineApplicable;
+     if let ExprKind::Lit(spanned) = &join_arg.kind;
+     if let LitKind::Str(symbol, _) = spanned.node;
+     if symbol.as_str().starts_with('/') || symbol.as_str().starts_with('\\');
      then {
       span_lint_and_sugg(
       cx,
       PATH_JOIN_CORRECTION,
       span.with_hi(expr.span.hi()),
-           r#"argument in join called on path contains a starting '/'"#,
-           "try removing first '/' or '\\'",
-           "join(\"your/path/here\")".to_owned(),
-           applicability
-         );
-        }
-        );
+      r#"argument in join called on path contains a starting '/'"#,
+      "try removing first '/' or '\\'",
+      "join(\"your/path/here\")".to_owned(),
+      applicability
+      );
+     }
+    );
 }