diff --git a/clippy_lints/src/methods/chars_cmp.rs b/clippy_lints/src/methods/chars_cmp.rs new file mode 100644 index 000000000000..f9af06d200c8 --- /dev/null +++ b/clippy_lints/src/methods/chars_cmp.rs @@ -0,0 +1,54 @@ +use crate::utils::{method_chain_args, single_segment_path}; +use clippy_utils::diagnostics::span_lint_and_sugg; +use clippy_utils::source::snippet_with_applicability; +use if_chain::if_chain; +use rustc_errors::Applicability; +use rustc_hir as hir; +use rustc_lint::LateContext; +use rustc_lint::Lint; +use rustc_middle::ty; +use rustc_span::sym; + +/// Wrapper fn for `CHARS_NEXT_CMP` and `CHARS_LAST_CMP` lints. +pub(super) fn check( + cx: &LateContext<'_>, + info: &crate::methods::BinaryExprInfo<'_>, + chain_methods: &[&str], + lint: &'static Lint, + suggest: &str, +) -> bool { + if_chain! { + if let Some(args) = method_chain_args(info.chain, chain_methods); + if let hir::ExprKind::Call(ref fun, ref arg_char) = info.other.kind; + if arg_char.len() == 1; + if let hir::ExprKind::Path(ref qpath) = fun.kind; + if let Some(segment) = single_segment_path(qpath); + if segment.ident.name == sym::Some; + then { + let mut applicability = Applicability::MachineApplicable; + let self_ty = cx.typeck_results().expr_ty_adjusted(&args[0][0]).peel_refs(); + + if *self_ty.kind() != ty::Str { + return false; + } + + span_lint_and_sugg( + cx, + lint, + info.expr.span, + &format!("you should use the `{}` method", suggest), + "like this", + format!("{}{}.{}({})", + if info.eq { "" } else { "!" }, + snippet_with_applicability(cx, args[0][0].span, "..", &mut applicability), + suggest, + snippet_with_applicability(cx, arg_char[0].span, "..", &mut applicability)), + applicability, + ); + + return true; + } + } + + false +} diff --git a/clippy_lints/src/methods/chars_next_cmp.rs b/clippy_lints/src/methods/chars_next_cmp.rs new file mode 100644 index 000000000000..a6701d8830e7 --- /dev/null +++ b/clippy_lints/src/methods/chars_next_cmp.rs @@ -0,0 +1,8 @@ +use rustc_lint::LateContext; + +use super::CHARS_NEXT_CMP; + +/// Checks for the `CHARS_NEXT_CMP` lint. +pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, info: &crate::methods::BinaryExprInfo<'_>) -> bool { + crate::methods::chars_cmp::check(cx, info, &["chars", "next"], CHARS_NEXT_CMP, "starts_with") +} diff --git a/clippy_lints/src/methods/mod.rs b/clippy_lints/src/methods/mod.rs index cbfb350ebb13..d288c51907e2 100644 --- a/clippy_lints/src/methods/mod.rs +++ b/clippy_lints/src/methods/mod.rs @@ -1,5 +1,7 @@ mod bind_instead_of_map; mod bytes_nth; +mod chars_cmp; +mod chars_next_cmp; mod clone_on_copy; mod clone_on_ref_ptr; mod expect_fun_call; @@ -2024,7 +2026,7 @@ struct BinaryExprInfo<'a> { /// Checks for the `CHARS_NEXT_CMP` and `CHARS_LAST_CMP` lints. fn lint_binary_expr_with_method_call(cx: &LateContext<'_>, info: &mut BinaryExprInfo<'_>) { macro_rules! lint_with_both_lhs_and_rhs { - ($func:ident, $cx:expr, $info:ident) => { + ($func:expr, $cx:expr, $info:ident) => { if !$func($cx, $info) { ::std::mem::swap(&mut $info.chain, &mut $info.other); if $func($cx, $info) { @@ -2034,67 +2036,18 @@ fn lint_binary_expr_with_method_call(cx: &LateContext<'_>, info: &mut BinaryExpr }; } - lint_with_both_lhs_and_rhs!(lint_chars_next_cmp, cx, info); + lint_with_both_lhs_and_rhs!(chars_next_cmp::check, cx, info); lint_with_both_lhs_and_rhs!(lint_chars_last_cmp, cx, info); lint_with_both_lhs_and_rhs!(lint_chars_next_cmp_with_unwrap, cx, info); lint_with_both_lhs_and_rhs!(lint_chars_last_cmp_with_unwrap, cx, info); } -/// Wrapper fn for `CHARS_NEXT_CMP` and `CHARS_LAST_CMP` lints. -fn lint_chars_cmp( - cx: &LateContext<'_>, - info: &BinaryExprInfo<'_>, - chain_methods: &[&str], - lint: &'static Lint, - suggest: &str, -) -> bool { - if_chain! { - if let Some(args) = method_chain_args(info.chain, chain_methods); - if let hir::ExprKind::Call(ref fun, ref arg_char) = info.other.kind; - if arg_char.len() == 1; - if let hir::ExprKind::Path(ref qpath) = fun.kind; - if let Some(segment) = single_segment_path(qpath); - if segment.ident.name == sym::Some; - then { - let mut applicability = Applicability::MachineApplicable; - let self_ty = cx.typeck_results().expr_ty_adjusted(&args[0][0]).peel_refs(); - - if *self_ty.kind() != ty::Str { - return false; - } - - span_lint_and_sugg( - cx, - lint, - info.expr.span, - &format!("you should use the `{}` method", suggest), - "like this", - format!("{}{}.{}({})", - if info.eq { "" } else { "!" }, - snippet_with_applicability(cx, args[0][0].span, "..", &mut applicability), - suggest, - snippet_with_applicability(cx, arg_char[0].span, "..", &mut applicability)), - applicability, - ); - - return true; - } - } - - false -} - -/// Checks for the `CHARS_NEXT_CMP` lint. -fn lint_chars_next_cmp<'tcx>(cx: &LateContext<'tcx>, info: &BinaryExprInfo<'_>) -> bool { - lint_chars_cmp(cx, info, &["chars", "next"], CHARS_NEXT_CMP, "starts_with") -} - /// Checks for the `CHARS_LAST_CMP` lint. fn lint_chars_last_cmp<'tcx>(cx: &LateContext<'tcx>, info: &BinaryExprInfo<'_>) -> bool { - if lint_chars_cmp(cx, info, &["chars", "last"], CHARS_LAST_CMP, "ends_with") { + if chars_cmp::check(cx, info, &["chars", "last"], CHARS_LAST_CMP, "ends_with") { true } else { - lint_chars_cmp(cx, info, &["chars", "next_back"], CHARS_LAST_CMP, "ends_with") + chars_cmp::check(cx, info, &["chars", "next_back"], CHARS_LAST_CMP, "ends_with") } }