diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/manual_ok_or.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/manual_ok_or.rs | 98 |
1 files changed, 0 insertions, 98 deletions
diff --git a/src/tools/clippy/clippy_lints/src/manual_ok_or.rs b/src/tools/clippy/clippy_lints/src/manual_ok_or.rs deleted file mode 100644 index 9abf2507b..000000000 --- a/src/tools/clippy/clippy_lints/src/manual_ok_or.rs +++ /dev/null @@ -1,98 +0,0 @@ -use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt}; -use clippy_utils::ty::is_type_diagnostic_item; -use clippy_utils::{is_lang_ctor, path_to_local_id}; -use if_chain::if_chain; -use rustc_errors::Applicability; -use rustc_hir::LangItem::{ResultErr, ResultOk}; -use rustc_hir::{Closure, Expr, ExprKind, PatKind}; -use rustc_lint::LintContext; -use rustc_lint::{LateContext, LateLintPass}; -use rustc_middle::lint::in_external_macro; -use rustc_session::{declare_lint_pass, declare_tool_lint}; -use rustc_span::symbol::sym; - -declare_clippy_lint! { - /// ### What it does - /// - /// Finds patterns that reimplement `Option::ok_or`. - /// - /// ### Why is this bad? - /// - /// Concise code helps focusing on behavior instead of boilerplate. - /// - /// ### Examples - /// ```rust - /// let foo: Option<i32> = None; - /// foo.map_or(Err("error"), |v| Ok(v)); - /// ``` - /// - /// Use instead: - /// ```rust - /// let foo: Option<i32> = None; - /// foo.ok_or("error"); - /// ``` - #[clippy::version = "1.49.0"] - pub MANUAL_OK_OR, - pedantic, - "finds patterns that can be encoded more concisely with `Option::ok_or`" -} - -declare_lint_pass!(ManualOkOr => [MANUAL_OK_OR]); - -impl<'tcx> LateLintPass<'tcx> for ManualOkOr { - fn check_expr(&mut self, cx: &LateContext<'tcx>, scrutinee: &'tcx Expr<'tcx>) { - if in_external_macro(cx.sess(), scrutinee.span) { - return; - } - - if_chain! { - if let ExprKind::MethodCall(method_segment, args, _) = scrutinee.kind; - if method_segment.ident.name == sym!(map_or); - if args.len() == 3; - let method_receiver = &args[0]; - let ty = cx.typeck_results().expr_ty(method_receiver); - if is_type_diagnostic_item(cx, ty, sym::Option); - let or_expr = &args[1]; - if is_ok_wrapping(cx, &args[2]); - if let ExprKind::Call(Expr { kind: ExprKind::Path(err_path), .. }, &[ref err_arg]) = or_expr.kind; - if is_lang_ctor(cx, err_path, ResultErr); - if let Some(method_receiver_snippet) = snippet_opt(cx, method_receiver.span); - if let Some(err_arg_snippet) = snippet_opt(cx, err_arg.span); - if let Some(indent) = indent_of(cx, scrutinee.span); - then { - let reindented_err_arg_snippet = - reindent_multiline(err_arg_snippet.into(), true, Some(indent + 4)); - span_lint_and_sugg( - cx, - MANUAL_OK_OR, - scrutinee.span, - "this pattern reimplements `Option::ok_or`", - "replace with", - format!( - "{}.ok_or({})", - method_receiver_snippet, - reindented_err_arg_snippet - ), - Applicability::MachineApplicable, - ); - } - } - } -} - -fn is_ok_wrapping(cx: &LateContext<'_>, map_expr: &Expr<'_>) -> bool { - if let ExprKind::Path(ref qpath) = map_expr.kind { - if is_lang_ctor(cx, qpath, ResultOk) { - return true; - } - } - if_chain! { - if let ExprKind::Closure(&Closure { body, .. }) = map_expr.kind; - let body = cx.tcx.hir().body(body); - if let PatKind::Binding(_, param_id, ..) = body.params[0].pat.kind; - if let ExprKind::Call(Expr { kind: ExprKind::Path(ok_path), .. }, &[ref ok_arg]) = body.value.kind; - if is_lang_ctor(cx, ok_path, ResultOk); - then { path_to_local_id(ok_arg, param_id) } else { false } - } -} |