-use crate::utils::{is_type_diagnostic_item, iter_input_pats, method_chain_args, snippet, span_lint_and_then};
+use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::source::snippet;
+use clippy_utils::ty::is_type_diagnostic_item;
+use clippy_utils::{iter_input_pats, method_chain_args};
use if_chain::if_chain;
use rustc_errors::Applicability;
use rustc_hir as hir;
use rustc_middle::ty::{self, Ty};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::source_map::Span;
+use rustc_span::sym;
declare_clippy_lint! {
/// **What it does:** Checks for usage of `option.map(f)` where f is a function
// Calls can't be reduced any more
Some(expr.span)
},
- hir::ExprKind::Block(ref block, _) => {
- match (&block.stmts[..], block.expr.as_ref()) {
+ hir::ExprKind::Block(block, _) => {
+ match (block.stmts, block.expr.as_ref()) {
(&[], Some(inner_expr)) => {
// If block only contains an expression,
// reduce `{ X }` to `X`
// If block only contains statements,
// reduce `{ X; }` to `X` or `X;`
match inner_stmt.kind {
- hir::StmtKind::Local(ref local) => Some(local.span),
- hir::StmtKind::Expr(ref e) => Some(e.span),
+ hir::StmtKind::Local(local) => Some(local.span),
+ hir::StmtKind::Expr(e) => Some(e.span),
hir::StmtKind::Semi(..) => Some(inner_stmt.span),
hir::StmtKind::Item(..) => None,
}
cx: &LateContext<'tcx>,
expr: &hir::Expr<'_>,
) -> Option<(&'tcx hir::Param<'tcx>, &'tcx hir::Expr<'tcx>)> {
- if let hir::ExprKind::Closure(_, ref decl, inner_expr_id, _, _) = expr.kind {
+ if_chain! {
+ if let hir::ExprKind::Closure(_, decl, inner_expr_id, _, _) = expr.kind;
let body = cx.tcx.hir().body(inner_expr_id);
let body_expr = &body.value;
-
- if_chain! {
- if decl.inputs.len() == 1;
- if is_unit_expression(cx, body_expr);
- if let Some(binding) = iter_input_pats(&decl, body).next();
- then {
- return Some((binding, body_expr));
- }
+ if decl.inputs.len() == 1;
+ if is_unit_expression(cx, body_expr);
+ if let Some(binding) = iter_input_pats(decl, body).next();
+ then {
+ return Some((binding, body_expr));
}
}
None
let var_arg = &map_args[0];
let (map_type, variant, lint) =
- if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(var_arg), sym!(option_type)) {
+ if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(var_arg), sym::option_type) {
("Option", "Some", OPTION_MAP_UNIT_FN)
- } else if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(var_arg), sym!(result_type)) {
+ } else if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(var_arg), sym::result_type) {
("Result", "Ok", RESULT_MAP_UNIT_FN)
} else {
return;
return;
}
- if let hir::StmtKind::Semi(ref expr) = stmt.kind {
+ if let hir::StmtKind::Semi(expr) = stmt.kind {
if let Some(arglists) = method_chain_args(expr, &["map"]) {
lint_map_unit_fn(cx, stmt, expr, arglists[0]);
}