use crate::utils::{is_copy, is_self_ty, snippet, span_lint_and_sugg};
use if_chain::if_chain;
-use matches::matches;
-use rustc::session::config::Config as SessionConfig;
use rustc::ty;
use rustc_errors::Applicability;
use rustc_hir as hir;
use rustc_hir::intravisit::FnKind;
use rustc_hir::{Body, FnDecl, HirId, ItemKind, MutTy, Mutability, Node};
use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::config::Config as SessionConfig;
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::Span;
use rustc_target::abi::LayoutOf;