use rustc::hir::intravisit::{walk_block, walk_expr, walk_stmt, NestedVisitorMap, Visitor};
use rustc::hir::*;
use rustc::lint::{LateContext, LateLintPass, Lint, LintArray, LintPass};
-use rustc::{declare_tool_lint, lint_array};
+use rustc::{declare_lint_pass, declare_tool_lint};
use rustc_errors::Applicability;
-use syntax::ast::{LitKind, NodeId};
+use syntax::ast::LitKind;
use syntax_pos::symbol::Symbol;
-/// **What it does:** Checks slow zero-filled vector initialization
-///
-/// **Why is this bad?** These structures are non-idiomatic and less efficient than simply using
-/// `vec![0; len]`.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// let mut vec1 = Vec::with_capacity(len);
-/// vec1.resize(len, 0);
-///
-/// let mut vec2 = Vec::with_capacity(len);
-/// vec2.extend(repeat(0).take(len))
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks slow zero-filled vector initialization
+ ///
+ /// **Why is this bad?** These structures are non-idiomatic and less efficient than simply using
+ /// `vec![0; len]`.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// # use core::iter::repeat;
+ /// # let len = 4;
+ /// let mut vec1 = Vec::with_capacity(len);
+ /// vec1.resize(len, 0);
+ ///
+ /// let mut vec2 = Vec::with_capacity(len);
+ /// vec2.extend(repeat(0).take(len))
+ /// ```
pub SLOW_VECTOR_INITIALIZATION,
perf,
"slow vector initialization"
}
-#[derive(Copy, Clone, Default)]
-pub struct Pass;
-
-impl LintPass for Pass {
- fn get_lints(&self) -> LintArray {
- lint_array!(SLOW_VECTOR_INITIALIZATION,)
- }
-
- fn name(&self) -> &'static str {
- "SlowVectorInit"
- }
-}
+declare_lint_pass!(SlowVectorInit => [SLOW_VECTOR_INITIALIZATION]);
/// `VecAllocation` contains data regarding a vector allocated with `with_capacity` and then
/// assigned to a variable. For example, `let mut vec = Vec::with_capacity(0)` or
Resize(&'tcx Expr),
}
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for SlowVectorInit {
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
// Matches initialization on reassignements. For example: `vec = Vec::with_capacity(100)`
if_chain! {
len_expr: len_arg,
};
- Self::search_initialization(cx, vi, expr.id);
+ Self::search_initialization(cx, vi, expr.hir_id);
}
}
}
len_expr: len_arg,
};
- Self::search_initialization(cx, vi, stmt.id);
+ Self::search_initialization(cx, vi, stmt.hir_id);
}
}
}
}
-impl Pass {
+impl SlowVectorInit {
/// Checks if the given expression is `Vec::with_capacity(..)`. It will return the expression
/// of the first argument of `with_capacity` call if it matches or `None` if it does not.
fn is_vec_with_capacity(expr: &Expr) -> Option<&Expr> {
}
/// Search initialization for the given vector
- fn search_initialization<'tcx>(cx: &LateContext<'_, 'tcx>, vec_alloc: VecAllocation<'tcx>, parent_node: NodeId) {
+ fn search_initialization<'tcx>(cx: &LateContext<'_, 'tcx>, vec_alloc: VecAllocation<'tcx>, parent_node: HirId) {
let enclosing_body = get_enclosing_block(cx, parent_node);
if enclosing_body.is_none() {
/// `VectorInitializationVisitor` searches for unsafe or slow vector initializations for the given
/// vector.
-struct VectorInitializationVisitor<'a, 'tcx: 'a> {
+struct VectorInitializationVisitor<'a, 'tcx> {
cx: &'a LateContext<'a, 'tcx>,
- /// Contains the information
+ /// Contains the information.
vec_alloc: VecAllocation<'tcx>,
- /// Contains, if found, the slow initialization expression
+ /// Contains the slow initialization expression, if one was found.
slow_expression: Option<InitializationType<'tcx>>,
- /// true if the initialization of the vector has been found on the visited block
+ /// `true` if the initialization of the vector has been found on the visited block.
initialization_found: bool,
}
if self.initialization_found;
if let ExprKind::MethodCall(ref path, _, ref args) = expr.node;
if let ExprKind::Path(ref qpath_subj) = args[0].node;
- if match_qpath(&qpath_subj, &[&self.vec_alloc.variable_name.to_string()]);
- if path.ident.name == "extend";
+ if match_qpath(&qpath_subj, &[&*self.vec_alloc.variable_name.as_str()]);
+ if path.ident.name == sym!(extend);
if let Some(ref extend_arg) = args.get(1);
if self.is_repeat_take(extend_arg);
if self.initialization_found;
if let ExprKind::MethodCall(ref path, _, ref args) = expr.node;
if let ExprKind::Path(ref qpath_subj) = args[0].node;
- if match_qpath(&qpath_subj, &[&self.vec_alloc.variable_name.to_string()]);
- if path.ident.name == "resize";
+ if match_qpath(&qpath_subj, &[&*self.vec_alloc.variable_name.as_str()]);
+ if path.ident.name == sym!(resize);
if let (Some(ref len_arg), Some(fill_arg)) = (args.get(1), args.get(2));
// Check that is filled with 0
fn is_repeat_take(&self, expr: &Expr) -> bool {
if_chain! {
if let ExprKind::MethodCall(ref take_path, _, ref take_args) = expr.node;
- if take_path.ident.name == "take";
+ if take_path.ident.name == sym!(take);
// Check that take is applied to `repeat(0)`
if let Some(ref repeat_expr) = take_args.get(0);
fn visit_expr(&mut self, expr: &'tcx Expr) {
// Skip all the expressions previous to the vector initialization
- if self.vec_alloc.allocation_expr.id == expr.id {
+ if self.vec_alloc.allocation_expr.hir_id == expr.hir_id {
self.initialization_found = true;
}
projects / rust.git / blobdiff