diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs | 90 |
1 files changed, 62 insertions, 28 deletions
diff --git a/src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs b/src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs index 82d368bb8..1d9096ea6 100644 --- a/src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs +++ b/src/tools/clippy/clippy_lints/src/bool_assert_comparison.rs @@ -1,10 +1,12 @@ +use clippy_utils::diagnostics::span_lint_and_then; use clippy_utils::macros::{find_assert_eq_args, root_macro_call_first_node}; -use clippy_utils::{diagnostics::span_lint_and_sugg, ty::implements_trait}; +use clippy_utils::sugg::Sugg; +use clippy_utils::ty::{implements_trait, is_copy}; use rustc_ast::ast::LitKind; use rustc_errors::Applicability; use rustc_hir::{Expr, ExprKind, Lit}; -use rustc_lint::{LateContext, LateLintPass}; -use rustc_middle::ty; +use rustc_lint::{LateContext, LateLintPass, LintContext}; +use rustc_middle::ty::{self, Ty}; use rustc_session::{declare_lint_pass, declare_tool_lint}; use rustc_span::symbol::Ident; @@ -33,19 +35,19 @@ declare_clippy_lint! { declare_lint_pass!(BoolAssertComparison => [BOOL_ASSERT_COMPARISON]); -fn is_bool_lit(e: &Expr<'_>) -> bool { - matches!( - e.kind, - ExprKind::Lit(Lit { - node: LitKind::Bool(_), - .. - }) - ) && !e.span.from_expansion() +fn extract_bool_lit(e: &Expr<'_>) -> Option<bool> { + if let ExprKind::Lit(Lit { + node: LitKind::Bool(b), .. + }) = e.kind + && !e.span.from_expansion() + { + Some(b) + } else { + None + } } -fn is_impl_not_trait_with_bool_out(cx: &LateContext<'_>, e: &Expr<'_>) -> bool { - let ty = cx.typeck_results().expr_ty(e); - +fn is_impl_not_trait_with_bool_out<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { cx.tcx .lang_items() .not_trait() @@ -70,38 +72,70 @@ impl<'tcx> LateLintPass<'tcx> for BoolAssertComparison { fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { let Some(macro_call) = root_macro_call_first_node(cx, expr) else { return }; let macro_name = cx.tcx.item_name(macro_call.def_id); - if !matches!( - macro_name.as_str(), - "assert_eq" | "debug_assert_eq" | "assert_ne" | "debug_assert_ne" - ) { - return; - } + let eq_macro = match macro_name.as_str() { + "assert_eq" | "debug_assert_eq" => true, + "assert_ne" | "debug_assert_ne" => false, + _ => return, + }; let Some ((a, b, _)) = find_assert_eq_args(cx, expr, macro_call.expn) else { return }; - if !(is_bool_lit(a) ^ is_bool_lit(b)) { + + let a_span = a.span.source_callsite(); + let b_span = b.span.source_callsite(); + + let (lit_span, bool_value, non_lit_expr) = match (extract_bool_lit(a), extract_bool_lit(b)) { + // assert_eq!(true/false, b) + // ^^^^^^^^^^^^ + (Some(bool_value), None) => (a_span.until(b_span), bool_value, b), + // assert_eq!(a, true/false) + // ^^^^^^^^^^^^ + (None, Some(bool_value)) => (b_span.with_lo(a_span.hi()), bool_value, a), // If there are two boolean arguments, we definitely don't understand // what's going on, so better leave things as is... // // Or there is simply no boolean and then we can leave things as is! - return; - } + _ => return, + }; + + let non_lit_ty = cx.typeck_results().expr_ty(non_lit_expr); - if !is_impl_not_trait_with_bool_out(cx, a) || !is_impl_not_trait_with_bool_out(cx, b) { + if !is_impl_not_trait_with_bool_out(cx, non_lit_ty) { // At this point the expression which is not a boolean // literal does not implement Not trait with a bool output, // so we cannot suggest to rewrite our code return; } + if !is_copy(cx, non_lit_ty) { + // Only lint with types that are `Copy` because `assert!(x)` takes + // ownership of `x` whereas `assert_eq(x, true)` does not + return; + } + let macro_name = macro_name.as_str(); let non_eq_mac = ¯o_name[..macro_name.len() - 3]; - span_lint_and_sugg( + span_lint_and_then( cx, BOOL_ASSERT_COMPARISON, macro_call.span, &format!("used `{macro_name}!` with a literal bool"), - "replace it with", - format!("{non_eq_mac}!(..)"), - Applicability::MaybeIncorrect, + |diag| { + // assert_eq!(...) + // ^^^^^^^^^ + let name_span = cx.sess().source_map().span_until_char(macro_call.span, '!'); + + let mut suggestions = vec![(name_span, non_eq_mac.to_string()), (lit_span, String::new())]; + + if bool_value ^ eq_macro { + let Some(sugg) = Sugg::hir_opt(cx, non_lit_expr) else { return }; + suggestions.push((non_lit_expr.span, (!sugg).to_string())); + } + + diag.multipart_suggestion( + format!("replace it with `{non_eq_mac}!(..)`"), + suggestions, + Applicability::MachineApplicable, + ); + }, ); } } |