Adding upstream version 1.65.0+dfsg1.upstream/1.65.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 70 insertions, 0 deletions

diff --git a/src/tools/clippy/clippy_lints/src/methods/bytecount.rs b/src/tools/clippy/clippy_lints/src/methods/bytecount.rs
new file mode 100644
index 000000000..fef90f6eb
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/methods/bytecount.rs
@@ -0,0 +1,70 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::match_type;
+use clippy_utils::visitors::is_local_used;
+use clippy_utils::{path_to_local_id, paths, peel_blocks, peel_ref_operators, strip_pat_refs};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{BinOpKind, Closure, Expr, ExprKind, PatKind};
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, UintTy};
+use rustc_span::sym;
+
+use super::NAIVE_BYTECOUNT;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    filter_recv: &'tcx Expr<'_>,
+    filter_arg: &'tcx Expr<'_>,
+) {
+    if_chain! {
+        if let ExprKind::Closure(&Closure { body, .. }) = filter_arg.kind;
+        let body = cx.tcx.hir().body(body);
+        if let [param] = body.params;
+        if let PatKind::Binding(_, arg_id, _, _) = strip_pat_refs(param.pat).kind;
+        if let ExprKind::Binary(ref op, l, r) = body.value.kind;
+        if op.node == BinOpKind::Eq;
+        if match_type(cx,
+                    cx.typeck_results().expr_ty(filter_recv).peel_refs(),
+                    &paths::SLICE_ITER);
+        let operand_is_arg = |expr| {
+            let expr = peel_ref_operators(cx, peel_blocks(expr));
+            path_to_local_id(expr, arg_id)
+        };
+        let needle = if operand_is_arg(l) {
+            r
+        } else if operand_is_arg(r) {
+            l
+        } else {
+            return;
+        };
+        if ty::Uint(UintTy::U8) == *cx.typeck_results().expr_ty(needle).peel_refs().kind();
+        if !is_local_used(cx, needle, arg_id);
+        then {
+            let haystack = if let ExprKind::MethodCall(path, receiver, [], _) =
+                    filter_recv.kind {
+                let p = path.ident.name;
+                if p == sym::iter || p == sym!(iter_mut) {
+                    receiver
+                } else {
+                    filter_recv
+                }
+            } else {
+                filter_recv
+            };
+            let mut applicability = Applicability::MaybeIncorrect;
+            span_lint_and_sugg(
+                cx,
+                NAIVE_BYTECOUNT,
+                expr.span,
+                "you appear to be counting bytes the naive way",
+                "consider using the bytecount crate",
+                format!("bytecount::count({}, {})",
+                        snippet_with_applicability(cx, haystack.span, "..", &mut applicability),
+                        snippet_with_applicability(cx, needle.span, "..", &mut applicability)),
+                applicability,
+            );
+        }
+    };
+}