1 files changed, 77 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs b/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs
new file mode 100644
index 000000000..cacd05262
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/utils/internal_lints/compiler_lint_functions.rs
@@ -0,0 +1,77 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::ty::match_type;
+use clippy_utils::{is_lint_allowed, paths};
+use if_chain::if_chain;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
+    /// variant of the function.
+    ///
+    /// ### Why is this bad?
+    /// The `utils::*` variants also add a link to the Clippy documentation to the
+    /// warning/error messages.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// cx.span_lint(LINT_NAME, "message");
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust,ignore
+    /// utils::span_lint(cx, LINT_NAME, "message");
+    /// ```
+    pub COMPILER_LINT_FUNCTIONS,
+    internal,
+    "usage of the lint functions of the compiler instead of the utils::* variant"
+}
+
+impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]);
+
+#[derive(Clone, Default)]
+pub struct CompilerLintFunctions {
+    map: FxHashMap<&'static str, &'static str>,
+}
+
+impl CompilerLintFunctions {
+    #[must_use]
+    pub fn new() -> Self {
+        let mut map = FxHashMap::default();
+        map.insert("span_lint", "utils::span_lint");
+        map.insert("struct_span_lint", "utils::span_lint");
+        map.insert("lint", "utils::span_lint");
+        map.insert("span_lint_note", "utils::span_lint_and_note");
+        map.insert("span_lint_help", "utils::span_lint_and_help");
+        Self { map }
+    }
+}
+
+impl<'tcx> LateLintPass<'tcx> for CompilerLintFunctions {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
+        if is_lint_allowed(cx, COMPILER_LINT_FUNCTIONS, expr.hir_id) {
+            return;
+        }
+
+        if_chain! {
+            if let ExprKind::MethodCall(path, self_arg, _, _) = &expr.kind;
+            let fn_name = path.ident;
+            if let Some(sugg) = self.map.get(fn_name.as_str());
+            let ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
+            if match_type(cx, ty, &paths::EARLY_CONTEXT) || match_type(cx, ty, &paths::LATE_CONTEXT);
+            then {
+                span_lint_and_help(
+                    cx,
+                    COMPILER_LINT_FUNCTIONS,
+                    path.ident.span,
+                    "usage of a compiler lint function",
+                    None,
+                    &format!("please use the Clippy variant of this function: `{sugg}`"),
+                );
+            }
+        }
+    }
+}