Move BytesCountToLen into Methods lint pass

clippy_lints/src/bytes_count_to_len.rs

@@ -1,70 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{match_def_path, paths};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::sym;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// It checks for `str::bytes().count()` and suggests replacing it with
-    /// `str::len()`.
-    ///
-    /// ### Why is this bad?
-    /// `str::bytes().count()` is longer and may not be as performant as using
-    /// `str::len()`.
-    ///
-    /// ### Example
-    /// ```rust
-    /// "hello".bytes().count();
-    /// String::from("hello").bytes().count();
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// "hello".len();
-    /// String::from("hello").len();
-    /// ```
-    #[clippy::version = "1.62.0"]
-    pub BYTES_COUNT_TO_LEN,
-    complexity,
-    "Using `bytes().count()` when `len()` performs the same functionality"
-}
-
-declare_lint_pass!(BytesCountToLen => [BYTES_COUNT_TO_LEN]);
-
-impl<'tcx> LateLintPass<'tcx> for BytesCountToLen {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        if_chain! {
-            if let hir::ExprKind::MethodCall(_, expr_args, _) = &expr.kind;
-            if let Some(expr_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
-            if match_def_path(cx, expr_def_id, &paths::ITER_COUNT);
-
-            if let [bytes_expr] = &**expr_args;
-            if let hir::ExprKind::MethodCall(_, bytes_args, _) = &bytes_expr.kind;
-            if let Some(bytes_def_id) = cx.typeck_results().type_dependent_def_id(bytes_expr.hir_id);
-            if match_def_path(cx, bytes_def_id, &paths::STR_BYTES);
-
-            if let [str_expr] = &**bytes_args;
-            let ty = cx.typeck_results().expr_ty(str_expr).peel_refs();
-
-            if is_type_diagnostic_item(cx, ty, sym::String) || ty.kind() == &ty::Str;
-            then {
-                let mut applicability = Applicability::MachineApplicable;
-                span_lint_and_sugg(
-                    cx,
-                    BYTES_COUNT_TO_LEN,
-                    expr.span,
-                    "using long and hard to read `.bytes().count()`",
-                    "consider calling `.len()` instead",
-                    format!("{}.len()", snippet_with_applicability(cx, str_expr.span, "..", &mut applicability)),
-                    applicability
-                );
-            }
-        };
-    }
-}

clippy_lints/src/lib.register_all.rs

@@ -20,7 +20,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(booleans::NONMINIMAL_BOOL),
     LintId::of(booleans::OVERLY_COMPLEX_BOOL_EXPR),
     LintId::of(borrow_deref_ref::BORROW_DEREF_REF),
-    LintId::of(bytes_count_to_len::BYTES_COUNT_TO_LEN),
     LintId::of(casts::CAST_ABS_TO_UNSIGNED),
     LintId::of(casts::CAST_ENUM_CONSTRUCTOR),
     LintId::of(casts::CAST_ENUM_TRUNCATION),
@@ -151,6 +150,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(mem_replace::MEM_REPLACE_WITH_DEFAULT),
     LintId::of(mem_replace::MEM_REPLACE_WITH_UNINIT),
     LintId::of(methods::BIND_INSTEAD_OF_MAP),
+    LintId::of(methods::BYTES_COUNT_TO_LEN),
     LintId::of(methods::BYTES_NTH),
     LintId::of(methods::CHARS_LAST_CMP),
     LintId::of(methods::CHARS_NEXT_CMP),

clippy_lints/src/lib.register_complexity.rs

@@ -6,7 +6,6 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(attrs::DEPRECATED_CFG_ATTR),
     LintId::of(booleans::NONMINIMAL_BOOL),
     LintId::of(borrow_deref_ref::BORROW_DEREF_REF),
-    LintId::of(bytes_count_to_len::BYTES_COUNT_TO_LEN),
     LintId::of(casts::CHAR_LIT_AS_U8),
     LintId::of(casts::UNNECESSARY_CAST),
     LintId::of(dereference::EXPLICIT_AUTO_DEREF),
@@ -33,6 +32,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(matches::NEEDLESS_MATCH),
     LintId::of(matches::WILDCARD_IN_OR_PATTERNS),
     LintId::of(methods::BIND_INSTEAD_OF_MAP),
+    LintId::of(methods::BYTES_COUNT_TO_LEN),
     LintId::of(methods::CLONE_ON_COPY),
     LintId::of(methods::FILTER_MAP_IDENTITY),
     LintId::of(methods::FILTER_NEXT),

clippy_lints/src/lib.register_lints.rs

@@ -59,7 +59,6 @@ store.register_lints(&[
     booleans::NONMINIMAL_BOOL,
     booleans::OVERLY_COMPLEX_BOOL_EXPR,
     borrow_deref_ref::BORROW_DEREF_REF,
-    bytes_count_to_len::BYTES_COUNT_TO_LEN,
     cargo::CARGO_COMMON_METADATA,
     cargo::MULTIPLE_CRATE_VERSIONS,
     cargo::NEGATIVE_FEATURE_NAMES,
@@ -284,6 +283,7 @@ store.register_lints(&[
     mem_replace::MEM_REPLACE_WITH_DEFAULT,
     mem_replace::MEM_REPLACE_WITH_UNINIT,
     methods::BIND_INSTEAD_OF_MAP,
+    methods::BYTES_COUNT_TO_LEN,
     methods::BYTES_NTH,
     methods::CHARS_LAST_CMP,
     methods::CHARS_NEXT_CMP,

clippy_lints/src/lib.rs

@@ -180,7 +180,6 @@ mod blocks_in_if_conditions;
 mod bool_assert_comparison;
 mod booleans;
 mod borrow_deref_ref;
-mod bytes_count_to_len;
 mod cargo;
 mod case_sensitive_file_extension_comparisons;
 mod casts;
@@ -907,7 +906,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(unnecessary_owned_empty_strings::UnnecessaryOwnedEmptyStrings));
     store.register_early_pass(|| Box::new(pub_use::PubUse));
     store.register_late_pass(|| Box::new(format_push_string::FormatPushString));
-    store.register_late_pass(|| Box::new(bytes_count_to_len::BytesCountToLen));
     let max_include_file_size = conf.max_include_file_size;
     store.register_late_pass(move || Box::new(large_include_file::LargeIncludeFile::new(max_include_file_size)));
     store.register_late_pass(|| Box::new(strings::TrimSplitWhitespace));

clippy_lints/src/methods/bytes_count_to_len.rs

@@ -0,0 +1,37 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::is_type_diagnostic_item;
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+use rustc_span::sym;
+
+use super::BYTES_COUNT_TO_LEN;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'_>,
+    count_recv: &'tcx hir::Expr<'_>,
+    bytes_recv: &'tcx hir::Expr<'_>,
+) {
+    if_chain! {
+        if let Some(bytes_id) = cx.typeck_results().type_dependent_def_id(count_recv.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(bytes_id);
+        if cx.tcx.type_of(impl_id).is_str();
+        let ty = cx.typeck_results().expr_ty(bytes_recv).peel_refs();
+        if ty.is_str() || is_type_diagnostic_item(cx, ty, sym::String);
+        then {
+            let mut applicability = Applicability::MachineApplicable;
+            span_lint_and_sugg(
+                cx,
+                BYTES_COUNT_TO_LEN,
+                expr.span,
+                "using long and hard to read `.bytes().count()`",
+                "consider calling `.len()` instead",
+                format!("{}.len()", snippet_with_applicability(cx, bytes_recv.span, "..", &mut applicability)),
+                applicability
+            );
+        }
+    };
+}

clippy_lints/src/methods/mod.rs

@@ -1,5 +1,6 @@
 mod bind_instead_of_map;
 mod bytecount;
+mod bytes_count_to_len;
 mod bytes_nth;
 mod chars_cmp;
 mod chars_cmp_with_unwrap;
@@ -2402,6 +2403,31 @@ declare_clippy_lint! {
     "use of naive `<slice>.filter(|&x| x == y).count()` to count byte values"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// It checks for `str::bytes().count()` and suggests replacing it with
+    /// `str::len()`.
+    ///
+    /// ### Why is this bad?
+    /// `str::bytes().count()` is longer and may not be as performant as using
+    /// `str::len()`.
+    ///
+    /// ### Example
+    /// ```rust
+    /// "hello".bytes().count();
+    /// String::from("hello").bytes().count();
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// "hello".len();
+    /// String::from("hello").len();
+    /// ```
+    #[clippy::version = "1.62.0"]
+    pub BYTES_COUNT_TO_LEN,
+    complexity,
+    "Using `bytes().count()` when `len()` performs the same functionality"
+}
+
 pub struct Methods {
     avoid_breaking_exported_api: bool,
     msrv: Option<RustcVersion>,
@@ -2507,6 +2533,7 @@ impl_lint_pass!(Methods => [
     ITER_ON_SINGLE_ITEMS,
     ITER_ON_EMPTY_COLLECTIONS,
     NAIVE_BYTECOUNT,
+    BYTES_COUNT_TO_LEN,
 ]);
 
 /// Extracts a method call name, args, and `Span` of the method name.
@@ -2768,6 +2795,7 @@ impl Methods {
                     },
                     Some(("map", [_, arg], _)) => suspicious_map::check(cx, expr, recv, arg),
                     Some(("filter", [recv2, arg], _)) => bytecount::check(cx, expr, recv2, arg),
+                    Some(("bytes", [recv2], _)) => bytes_count_to_len::check(cx, expr, recv, recv2),
                     _ => {},
                 },
                 ("drain", [arg]) => {