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;
use syntax_pos::symbol::Symbol;
///
/// **Example:**
/// ```rust
+ /// # use core::iter::repeat;
+ /// # let len = 4;
/// let mut vec1 = Vec::with_capacity(len);
/// vec1.resize(len, 0);
///
"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! {
}
}
-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> {
/// `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);