diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs b/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs new file mode 100644 index 000000000..b3c2c7c9a --- /dev/null +++ b/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs @@ -0,0 +1,41 @@ +use clippy_utils::diagnostics::span_lint_and_help; +use clippy_utils::ty::is_type_diagnostic_item; +use if_chain::if_chain; +use rustc_ast::ast::LitKind; +use rustc_hir::{Expr, ExprKind}; +use rustc_lint::LateContext; +use rustc_span::{source_map::Spanned, symbol::sym, Span}; + +use super::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS; + +pub(super) fn check<'tcx>( + cx: &LateContext<'tcx>, + expr: &'tcx Expr<'_>, + call_span: Span, + recv: &'tcx Expr<'_>, + arg: &'tcx Expr<'_>, +) { + if_chain! { + if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id); + if let Some(impl_id) = cx.tcx.impl_of_method(method_id); + if cx.tcx.type_of(impl_id).is_str(); + if let ExprKind::Lit(Spanned { node: LitKind::Str(ext_literal, ..), ..}) = arg.kind; + if (2..=6).contains(&ext_literal.as_str().len()); + let ext_str = ext_literal.as_str(); + if ext_str.starts_with('.'); + if ext_str.chars().skip(1).all(|c| c.is_uppercase() || c.is_ascii_digit()) + || ext_str.chars().skip(1).all(|c| c.is_lowercase() || c.is_ascii_digit()); + let recv_ty = cx.typeck_results().expr_ty(recv).peel_refs(); + if recv_ty.is_str() || is_type_diagnostic_item(cx, recv_ty, sym::String); + then { + span_lint_and_help( + cx, + CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS, + call_span, + "case-sensitive file extension comparison", + None, + "consider using a case-insensitive comparison instead", + ); + } + } +} |