Misc doc updates

Author: ebroto

clippy_lints/src/utils/diagnostics.rs

@@ -51,6 +51,8 @@ pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<Mult
 ///
 /// The `help` message can be optionally attached to a `Span`.
 ///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
 /// # Example
 ///
 /// ```ignore
@@ -87,6 +89,8 @@ pub fn span_lint_and_help<'a, T: LintContext>(
 /// The `note` message is presented separately from the main lint message
 /// and is attached to a specific span:
 ///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
 /// # Example
 ///
 /// ```ignore
@@ -126,6 +130,7 @@ pub fn span_lint_and_note<'a, T: LintContext>(
 /// Like `span_lint` but allows to add notes, help and suggestions using a closure.
 ///
 /// If you need to customize your lint output a lot, use this function.
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
 pub fn span_lint_and_then<'a, T: LintContext, F>(cx: &'a T, lint: &'static Lint, sp: Span, msg: &str, f: F)
 where
     F: for<'b> FnOnce(&mut DiagnosticBuilder<'b>),
@@ -168,6 +173,10 @@ pub fn span_lint_hir_and_then(
 /// In the example below, `help` is `"try"` and `sugg` is the suggested replacement `".any(|x| x >
 /// 2)"`.
 ///
+/// If you change the signature, remember to update the internal lint `CollapsibleCalls`
+///
+/// # Example
+///
 /// ```ignore
 /// error: This `.fold` can be more succinctly expressed as `.any`
 /// --> $DIR/methods.rs:390:13

doc/common_tools_writing_lints.md

@@ -60,7 +60,7 @@ impl LateLintPass<'_> for MyStructLint {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
         if_chain! {
             // Check our expr is calling a method
-            if let hir::ExprKind::MethodCall(path, _, _args) = &expr.kind;
+            if let hir::ExprKind::MethodCall(path, _, _args, _) = &expr.kind;
             // Check the name of this method is `some_method`
             if path.ident.name == sym!(some_method);
             then {