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-rw-r--r--src/tools/clippy/clippy_lints/src/get_first.rs68
1 files changed, 0 insertions, 68 deletions
diff --git a/src/tools/clippy/clippy_lints/src/get_first.rs b/src/tools/clippy/clippy_lints/src/get_first.rs
deleted file mode 100644
index 529f7baba..000000000
--- a/src/tools/clippy/clippy_lints/src/get_first.rs
+++ /dev/null
@@ -1,68 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::{is_slice_of_primitives, match_def_path, paths};
-use if_chain::if_chain;
-use rustc_ast::LitKind;
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::source_map::Spanned;
-
-declare_clippy_lint! {
- /// ### What it does
- /// Checks for using `x.get(0)` instead of
- /// `x.first()`.
- ///
- /// ### Why is this bad?
- /// Using `x.first()` is easier to read and has the same
- /// result.
- ///
- /// ### Example
- /// ```rust
- /// let x = vec![2, 3, 5];
- /// let first_element = x.get(0);
- /// ```
- ///
- /// Use instead:
- /// ```rust
- /// let x = vec![2, 3, 5];
- /// let first_element = x.first();
- /// ```
- #[clippy::version = "1.63.0"]
- pub GET_FIRST,
- style,
- "Using `x.get(0)` when `x.first()` is simpler"
-}
-declare_lint_pass!(GetFirst => [GET_FIRST]);
-
-impl<'tcx> LateLintPass<'tcx> for GetFirst {
- fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
- if_chain! {
- if let hir::ExprKind::MethodCall(_, [struct_calling_on, method_arg], _) = &expr.kind;
- if let Some(expr_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
- if match_def_path(cx, expr_def_id, &paths::SLICE_GET);
-
- if let Some(_) = is_slice_of_primitives(cx, struct_calling_on);
- if let hir::ExprKind::Lit(Spanned { node: LitKind::Int(0, _), .. }) = method_arg.kind;
-
- then {
- let mut applicability = Applicability::MachineApplicable;
- let slice_name = snippet_with_applicability(
- cx,
- struct_calling_on.span, "..",
- &mut applicability,
- );
- span_lint_and_sugg(
- cx,
- GET_FIRST,
- expr.span,
- &format!("accessing first element with `{0}.get(0)`", slice_name),
- "try",
- format!("{}.first()", slice_name),
- applicability,
- );
- }
- }
- }
-}