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-rw-r--r--src/tools/clippy/clippy_lints/src/repeat_once.rs89
1 files changed, 0 insertions, 89 deletions
diff --git a/src/tools/clippy/clippy_lints/src/repeat_once.rs b/src/tools/clippy/clippy_lints/src/repeat_once.rs
deleted file mode 100644
index 898c70ace..000000000
--- a/src/tools/clippy/clippy_lints/src/repeat_once.rs
+++ /dev/null
@@ -1,89 +0,0 @@
-use clippy_utils::consts::{constant_context, Constant};
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet;
-use clippy_utils::ty::is_type_diagnostic_item;
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::sym;
-
-declare_clippy_lint! {
- /// ### What it does
- /// Checks for usage of `.repeat(1)` and suggest the following method for each types.
- /// - `.to_string()` for `str`
- /// - `.clone()` for `String`
- /// - `.to_vec()` for `slice`
- ///
- /// The lint will evaluate constant expressions and values as arguments of `.repeat(..)` and emit a message if
- /// they are equivalent to `1`. (Related discussion in [rust-clippy#7306](https://github.com/rust-lang/rust-clippy/issues/7306))
- ///
- /// ### Why is this bad?
- /// For example, `String.repeat(1)` is equivalent to `.clone()`. If cloning
- /// the string is the intention behind this, `clone()` should be used.
- ///
- /// ### Example
- /// ```rust
- /// fn main() {
- /// let x = String::from("hello world").repeat(1);
- /// }
- /// ```
- /// Use instead:
- /// ```rust
- /// fn main() {
- /// let x = String::from("hello world").clone();
- /// }
- /// ```
- #[clippy::version = "1.47.0"]
- pub REPEAT_ONCE,
- complexity,
- "using `.repeat(1)` instead of `String.clone()`, `str.to_string()` or `slice.to_vec()` "
-}
-
-declare_lint_pass!(RepeatOnce => [REPEAT_ONCE]);
-
-impl<'tcx> LateLintPass<'tcx> for RepeatOnce {
- fn check_expr(&mut self, cx: &LateContext<'_>, expr: &'tcx Expr<'_>) {
- if_chain! {
- if let ExprKind::MethodCall(path, [receiver, count], _) = &expr.kind;
- if path.ident.name == sym!(repeat);
- if constant_context(cx, cx.typeck_results()).expr(count) == Some(Constant::Int(1));
- if !receiver.span.from_expansion();
- then {
- let ty = cx.typeck_results().expr_ty(receiver).peel_refs();
- if ty.is_str() {
- span_lint_and_sugg(
- cx,
- REPEAT_ONCE,
- expr.span,
- "calling `repeat(1)` on str",
- "consider using `.to_string()` instead",
- format!("{}.to_string()", snippet(cx, receiver.span, r#""...""#)),
- Applicability::MachineApplicable,
- );
- } else if ty.builtin_index().is_some() {
- span_lint_and_sugg(
- cx,
- REPEAT_ONCE,
- expr.span,
- "calling `repeat(1)` on slice",
- "consider using `.to_vec()` instead",
- format!("{}.to_vec()", snippet(cx, receiver.span, r#""...""#)),
- Applicability::MachineApplicable,
- );
- } else if is_type_diagnostic_item(cx, ty, sym::String) {
- span_lint_and_sugg(
- cx,
- REPEAT_ONCE,
- expr.span,
- "calling `repeat(1)` on a string literal",
- "consider using `.clone()` instead",
- format!("{}.clone()", snippet(cx, receiver.span, r#""...""#)),
- Applicability::MachineApplicable,
- );
- }
- }
- }
- }
-}