diff --git a/clippy_lints/src/loops/same_item_push.rs b/clippy_lints/src/loops/same_item_push.rs
index f7b3b2358a0..5fffb27cda2 100644
--- a/clippy_lints/src/loops/same_item_push.rs
+++ b/clippy_lints/src/loops/same_item_push.rs
@@ -185,7 +185,7 @@ fn get_vec_push<'tcx>(
if let StmtKind::Semi(semi_stmt) = &stmt.kind;
if let ExprKind::MethodCall(path, self_expr, args, _) = &semi_stmt.kind;
// Figure out the parameters for the method call
- if let Some(pushed_item) = args.get(0);
+ if let Some(pushed_item) = args.first();
// Check that the method being called is push() on a Vec
if is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(self_expr), sym::Vec);
if path.ident.name.as_str() == "push";
diff --git a/clippy_lints/src/manual_bits.rs b/clippy_lints/src/manual_bits.rs
index 6c7c57ba1d6..552c57d5e02 100644
--- a/clippy_lints/src/manual_bits.rs
+++ b/clippy_lints/src/manual_bits.rs
@@ -103,9 +103,9 @@ fn get_size_of_ty<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<
if let ExprKind::Path(ref count_func_qpath) = count_func.kind;
if let QPath::Resolved(_, count_func_path) = count_func_qpath;
- if let Some(segment_zero) = count_func_path.segments.get(0);
+ if let Some(segment_zero) = count_func_path.segments.first();
if let Some(args) = segment_zero.args;
- if let Some(GenericArg::Type(real_ty)) = args.args.get(0);
+ if let Some(GenericArg::Type(real_ty)) = args.args.first();
if let Some(def_id) = cx.qpath_res(count_func_qpath, count_func.hir_id).opt_def_id();
if cx.tcx.is_diagnostic_item(sym::mem_size_of, def_id);
diff --git a/clippy_lints/src/methods/get_first.rs b/clippy_lints/src/methods/get_first.rs
index ee063adac64..e7b4564c651 100644
--- a/clippy_lints/src/methods/get_first.rs
+++ b/clippy_lints/src/methods/get_first.rs
@@ -1,5 +1,4 @@
use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::is_slice_of_primitives;
use clippy_utils::source::snippet_with_applicability;
use if_chain::if_chain;
use rustc_ast::LitKind;
@@ -20,7 +19,6 @@ pub(super) fn check<'tcx>(
if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
if cx.tcx.type_of(impl_id).instantiate_identity().is_slice();
- if let Some(_) = is_slice_of_primitives(cx, recv);
if let hir::ExprKind::Lit(Spanned { node: LitKind::Int(0, _), .. }) = arg.kind;
then {
let mut app = Applicability::MachineApplicable;
diff --git a/clippy_lints/src/methods/search_is_some.rs b/clippy_lints/src/methods/search_is_some.rs
index afdb8ce94ac..04ddaaa2f46 100644
--- a/clippy_lints/src/methods/search_is_some.rs
+++ b/clippy_lints/src/methods/search_is_some.rs
@@ -39,7 +39,7 @@ pub(super) fn check<'tcx>(
if search_method == "find";
if let hir::ExprKind::Closure(&hir::Closure { body, .. }) = search_arg.kind;
let closure_body = cx.tcx.hir().body(body);
- if let Some(closure_arg) = closure_body.params.get(0);
+ if let Some(closure_arg) = closure_body.params.first();
then {
if let hir::PatKind::Ref(..) = closure_arg.pat.kind {
Some(search_snippet.replacen('&', "", 1))
diff --git a/clippy_lints/src/missing_doc.rs b/clippy_lints/src/missing_doc.rs
index f2773cad400..0629dee4f72 100644
--- a/clippy_lints/src/missing_doc.rs
+++ b/clippy_lints/src/missing_doc.rs
@@ -67,7 +67,7 @@ impl MissingDoc {
if_chain! {
if let Some(meta) = meta;
if let MetaItemKind::List(list) = meta.kind;
- if let Some(meta) = list.get(0);
+ if let Some(meta) = list.first();
if let Some(name) = meta.ident();
then {
name.name == sym::include
diff --git a/clippy_lints/src/needless_continue.rs b/clippy_lints/src/needless_continue.rs
index 38a75034cd3..377cbef7b99 100644
--- a/clippy_lints/src/needless_continue.rs
+++ b/clippy_lints/src/needless_continue.rs
@@ -189,7 +189,7 @@ fn needless_continue_in_else(else_expr: &ast::Expr, label: Option<&ast::Label>)
}
fn is_first_block_stmt_continue(block: &ast::Block, label: Option<&ast::Label>) -> bool {
- block.stmts.get(0).map_or(false, |stmt| match stmt.kind {
+ block.stmts.first().map_or(false, |stmt| match stmt.kind {
ast::StmtKind::Semi(ref e) | ast::StmtKind::Expr(ref e) => {
if let ast::ExprKind::Continue(ref l) = e.kind {
compare_labels(label, l.as_ref())
@@ -434,7 +434,7 @@ fn erode_from_back(s: &str) -> String {
}
fn span_of_first_expr_in_block(block: &ast::Block) -> Option<Span> {
- block.stmts.get(0).map(|stmt| stmt.span)
+ block.stmts.first().map(|stmt| stmt.span)
}
#[cfg(test)]
diff --git a/clippy_lints/src/slow_vector_initialization.rs b/clippy_lints/src/slow_vector_initialization.rs
index 9db18c2976c..2278e41be37 100644
--- a/clippy_lints/src/slow_vector_initialization.rs
+++ b/clippy_lints/src/slow_vector_initialization.rs
@@ -335,7 +335,7 @@ impl<'a, 'tcx> Visitor<'tcx> for VectorInitializationVisitor<'a, 'tcx> {
fn visit_block(&mut self, block: &'tcx Block<'_>) {
if self.initialization_found {
- if let Some(s) = block.stmts.get(0) {
+ if let Some(s) = block.stmts.first() {
self.visit_stmt(s);
}
diff --git a/clippy_lints/src/uninit_vec.rs b/clippy_lints/src/uninit_vec.rs
index 6756df8e716..72569e10f05 100644
--- a/clippy_lints/src/uninit_vec.rs
+++ b/clippy_lints/src/uninit_vec.rs
@@ -201,7 +201,7 @@ fn extract_set_len_self<'tcx>(cx: &LateContext<'_>, expr: &'tcx Expr<'_>) -> Opt
let expr = peel_hir_expr_while(expr, |e| {
if let ExprKind::Block(block, _) = e.kind {
// Extract the first statement/expression
- match (block.stmts.get(0).map(|stmt| &stmt.kind), block.expr) {
+ match (block.stmts.first().map(|stmt| &stmt.kind), block.expr) {
(None, Some(expr)) => Some(expr),
(Some(StmtKind::Expr(expr) | StmtKind::Semi(expr)), _) => Some(expr),
_ => None,
diff --git a/clippy_lints/src/unnecessary_map_on_constructor.rs b/clippy_lints/src/unnecessary_map_on_constructor.rs
index 5aa057580e9..894de0d85c1 100644
--- a/clippy_lints/src/unnecessary_map_on_constructor.rs
+++ b/clippy_lints/src/unnecessary_map_on_constructor.rs
@@ -40,7 +40,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryMapOnConstructor {
let (constructor_path, constructor_item) =
if let hir::ExprKind::Call(constructor, constructor_args) = recv.kind
&& let hir::ExprKind::Path(constructor_path) = constructor.kind
- && let Some(arg) = constructor_args.get(0)
+ && let Some(arg) = constructor_args.first()
{
if constructor.span.from_expansion() || arg.span.from_expansion() {
return;
@@ -66,7 +66,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryMapOnConstructor {
_ => return,
}
- if let Some(map_arg) = args.get(0)
+ if let Some(map_arg) = args.first()
&& let hir::ExprKind::Path(fun) = map_arg.kind
{
if map_arg.span.from_expansion() {
diff --git a/clippy_utils/src/consts.rs b/clippy_utils/src/consts.rs
index 0bae7056c4f..79c04c7c7f4 100644
--- a/clippy_utils/src/consts.rs
+++ b/clippy_utils/src/consts.rs
@@ -504,7 +504,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
},
(Some(Constant::Vec(vec)), _) => {
if !vec.is_empty() && vec.iter().all(|x| *x == vec[0]) {
- match vec.get(0) {
+ match vec.first() {
Some(Constant::F32(x)) => Some(Constant::F32(*x)),
Some(Constant::F64(x)) => Some(Constant::F64(*x)),
_ => None,
diff --git a/clippy_utils/src/higher.rs b/clippy_utils/src/higher.rs
index 802adbd4d2d..7c1be625bd3 100644
--- a/clippy_utils/src/higher.rs
+++ b/clippy_utils/src/higher.rs
@@ -449,7 +449,7 @@ pub fn get_vec_init_kind<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -
} else if name.ident.name == symbol::kw::Default {
return Some(VecInitKind::Default);
} else if name.ident.name.as_str() == "with_capacity" {
- let arg = args.get(0)?;
+ let arg = args.first()?;
return match constant_simple(cx, cx.typeck_results(), arg) {
Some(Constant::Int(num)) => Some(VecInitKind::WithConstCapacity(num)),
_ => Some(VecInitKind::WithExprCapacity(arg.hir_id)),
diff --git a/tests/ui/get_first.fixed b/tests/ui/get_first.fixed
index b1a597fc4dd..a7cdd2a93ba 100644
--- a/tests/ui/get_first.fixed
+++ b/tests/ui/get_first.fixed
@@ -14,17 +14,20 @@ impl Bar {
fn main() {
let x = vec![2, 3, 5];
- let _ = x.first(); // Use x.first()
+ let _ = x.first();
+ //~^ ERROR: accessing first element with `x.get(0)`
let _ = x.get(1);
let _ = x[0];
let y = [2, 3, 5];
- let _ = y.first(); // Use y.first()
+ let _ = y.first();
+ //~^ ERROR: accessing first element with `y.get(0)`
let _ = y.get(1);
let _ = y[0];
let z = &[2, 3, 5];
- let _ = z.first(); // Use z.first()
+ let _ = z.first();
+ //~^ ERROR: accessing first element with `z.get(0)`
let _ = z.get(1);
let _ = z[0];
@@ -37,4 +40,8 @@ fn main() {
let bar = Bar { arr: [0, 1, 2] };
let _ = bar.get(0); // Do not lint, because Bar is struct.
+
+ let non_primitives = [vec![1, 2], vec![3, 4]];
+ let _ = non_primitives.first();
+ //~^ ERROR: accessing first element with `non_primitives.get(0)`
}
diff --git a/tests/ui/get_first.rs b/tests/ui/get_first.rs
index e27ee4be8c0..cca743c4bf5 100644
--- a/tests/ui/get_first.rs
+++ b/tests/ui/get_first.rs
@@ -14,17 +14,20 @@ impl Bar {
fn main() {
let x = vec![2, 3, 5];
- let _ = x.get(0); // Use x.first()
+ let _ = x.get(0);
+ //~^ ERROR: accessing first element with `x.get(0)`
let _ = x.get(1);
let _ = x[0];
let y = [2, 3, 5];
- let _ = y.get(0); // Use y.first()
+ let _ = y.get(0);
+ //~^ ERROR: accessing first element with `y.get(0)`
let _ = y.get(1);
let _ = y[0];
let z = &[2, 3, 5];
- let _ = z.get(0); // Use z.first()
+ let _ = z.get(0);
+ //~^ ERROR: accessing first element with `z.get(0)`
let _ = z.get(1);
let _ = z[0];
@@ -37,4 +40,8 @@ fn main() {
let bar = Bar { arr: [0, 1, 2] };
let _ = bar.get(0); // Do not lint, because Bar is struct.
+
+ let non_primitives = [vec![1, 2], vec![3, 4]];
+ let _ = non_primitives.get(0);
+ //~^ ERROR: accessing first element with `non_primitives.get(0)`
}
diff --git a/tests/ui/get_first.stderr b/tests/ui/get_first.stderr
index 56b4c29a313..8ee66e33cc8 100644
--- a/tests/ui/get_first.stderr
+++ b/tests/ui/get_first.stderr
@@ -1,23 +1,29 @@
error: accessing first element with `x.get(0)`
--> $DIR/get_first.rs:17:13
|
-LL | let _ = x.get(0); // Use x.first()
+LL | let _ = x.get(0);
| ^^^^^^^^ help: try: `x.first()`
|
= note: `-D clippy::get-first` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::get_first)]`
error: accessing first element with `y.get(0)`
- --> $DIR/get_first.rs:22:13
+ --> $DIR/get_first.rs:23:13
|
-LL | let _ = y.get(0); // Use y.first()
+LL | let _ = y.get(0);
| ^^^^^^^^ help: try: `y.first()`
error: accessing first element with `z.get(0)`
- --> $DIR/get_first.rs:27:13
+ --> $DIR/get_first.rs:29:13
|
-LL | let _ = z.get(0); // Use z.first()
+LL | let _ = z.get(0);
| ^^^^^^^^ help: try: `z.first()`
-error: aborting due to 3 previous errors
+error: accessing first element with `non_primitives.get(0)`
+ --> $DIR/get_first.rs:45:13
+ |
+LL | let _ = non_primitives.get(0);
+ | ^^^^^^^^^^^^^^^^^^^^^ help: try: `non_primitives.first()`
+
+error: aborting due to 4 previous errors