use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::higher::{get_vec_init_kind, VecInitKind};
use clippy_utils::source::snippet;
-use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{match_def_path, path_to_local, path_to_local_id, paths};
+use clippy_utils::{path_to_local, path_to_local_id};
use if_chain::if_chain;
-use rustc_ast::ast::LitKind;
use rustc_errors::Applicability;
-use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, HirId, Local, PatKind, QPath, Stmt, StmtKind};
+use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, HirId, Local, PatKind, Stmt, StmtKind};
use rustc_lint::{LateContext, LateLintPass, LintContext};
use rustc_middle::lint::in_external_macro;
use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::{symbol::sym, Span};
-use std::convert::TryInto;
+use rustc_span::Span;
declare_clippy_lint! {
/// ### What it does
/// ```rust
/// let v = vec![0];
/// ```
+ #[clippy::version = "1.51.0"]
pub VEC_INIT_THEN_PUSH,
perf,
"`push` immediately after `Vec` creation"
searcher: Option<VecPushSearcher>,
}
-#[derive(Clone, Copy)]
-enum VecInitKind {
- New,
- WithCapacity(u64),
-}
struct VecPushSearcher {
local_id: HirId,
init: VecInitKind,
fn display_err(&self, cx: &LateContext<'_>) {
match self.init {
_ if self.found == 0 => return,
- VecInitKind::WithCapacity(x) if x > self.found => return,
+ VecInitKind::WithLiteralCapacity(x) if x > self.found => return,
+ VecInitKind::WithExprCapacity(_) => return,
_ => (),
};
}
}
-impl LateLintPass<'_> for VecInitThenPush {
+impl<'tcx> LateLintPass<'tcx> for VecInitThenPush {
fn check_block(&mut self, _: &LateContext<'tcx>, _: &'tcx Block<'tcx>) {
self.searcher = None;
}
if let Some(searcher) = self.searcher.take() {
if_chain! {
if let StmtKind::Expr(expr) | StmtKind::Semi(expr) = stmt.kind;
- if let ExprKind::MethodCall(path, _, [self_arg, _], _) = expr.kind;
+ if let ExprKind::MethodCall(path, [self_arg, _], _) = expr.kind;
if path_to_local_id(self_arg, searcher.local_id);
if path.ident.name.as_str() == "push";
then {
}
}
}
-
-fn get_vec_init_kind<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<VecInitKind> {
- if let ExprKind::Call(func, args) = expr.kind {
- match func.kind {
- ExprKind::Path(QPath::TypeRelative(ty, name))
- if is_type_diagnostic_item(cx, cx.typeck_results().node_type(ty.hir_id), sym::vec_type) =>
- {
- if name.ident.name == sym::new {
- return Some(VecInitKind::New);
- } else if name.ident.name.as_str() == "with_capacity" {
- return args.get(0).and_then(|arg| {
- if_chain! {
- if let ExprKind::Lit(lit) = &arg.kind;
- if let LitKind::Int(num, _) = lit.node;
- then {
- Some(VecInitKind::WithCapacity(num.try_into().ok()?))
- } else {
- None
- }
- }
- });
- }
- }
- ExprKind::Path(QPath::Resolved(_, path))
- if match_def_path(cx, path.res.opt_def_id()?, &paths::DEFAULT_TRAIT_METHOD)
- && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::vec_type) =>
- {
- return Some(VecInitKind::New);
- }
- _ => (),
- }
- }
- None
-}