-use crate::utils::span_lint;
+use crate::utils::{fn_def_id, span_lint};
use rustc_data_structures::fx::FxHashSet;
-use rustc_hir::{Expr, ExprKind};
+use rustc_hir::Expr;
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::Symbol;
declare_clippy_lint! {
- /// **What it does:** Lints for specific trait methods defined in clippy.toml
+ /// **What it does:** Denies the configured methods and functions in clippy.toml
///
/// **Why is this bad?** Some methods are undesirable in certain contexts,
- /// and it would be beneficial to lint for them as needed.
+ /// and it's beneficial to lint for them as needed.
///
- /// **Known problems:** None.
+ /// **Known problems:** Currently, you must write each function as a
+ /// fully-qualified path. This lint doesn't support aliases or reexported
+ /// names; be aware that many types in `std` are actually reexports.
+ ///
+ /// For example, if you want to disallow `Duration::as_secs`, your clippy.toml
+ /// configuration would look like
+ /// `disallowed-methods = ["core::time::Duration::as_secs"]` and not
+ /// `disallowed-methods = ["std::time::Duration::as_secs"]` as you might expect.
///
/// **Example:**
///
+ /// An example clippy.toml configuration:
+ /// ```toml
+ /// # clippy.toml
+ /// disallowed-methods = ["alloc::vec::Vec::leak", "std::time::Instant::now"]
+ /// ```
+ ///
/// ```rust,ignore
- /// // example code where clippy issues a warning
- /// foo.bad_method(); // Foo::bad_method is disallowed in the configuration
+ /// // Example code where clippy issues a warning
+ /// let xs = vec![1, 2, 3, 4];
+ /// xs.leak(); // Vec::leak is disallowed in the config.
+ ///
+ /// let _now = Instant::now(); // Instant::now is disallowed in the config.
/// ```
+ ///
/// Use instead:
/// ```rust,ignore
- /// // example code which does not raise clippy warning
- /// goodStruct.bad_method(); // GoodStruct::bad_method is not disallowed
+ /// // Example code which does not raise clippy warning
+ /// let mut xs = Vec::new(); // Vec::new is _not_ disallowed in the config.
+ /// xs.push(123); // Vec::push is _not_ disallowed in the config.
/// ```
pub DISALLOWED_METHOD,
nursery,
impl<'tcx> LateLintPass<'tcx> for DisallowedMethod {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
- if let ExprKind::MethodCall(_path, _, _args, _) = &expr.kind {
- let def_id = cx.typeck_results().type_dependent_def_id(expr.hir_id).unwrap();
-
- let method_call = cx.get_def_path(def_id);
- if self.disallowed.contains(&method_call) {
- let method = method_call
- .iter()
- .map(|s| s.to_ident_string())
+ if let Some(def_id) = fn_def_id(cx, expr) {
+ let func_path = cx.get_def_path(def_id);
+ if self.disallowed.contains(&func_path) {
+ let func_path_string = func_path
+ .into_iter()
+ .map(Symbol::to_ident_string)
.collect::<Vec<_>>()
.join("::");
cx,
DISALLOWED_METHOD,
expr.span,
- &format!("use of a disallowed method `{}`", method),
+ &format!("use of a disallowed method `{}`", func_path_string),
);
}
}