Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/src/tools/clippy/clippy_lints/src/methods/single_char_insert_string.rs b/src/tools/clippy/clippy_lints/src/methods/single_char_insert_string.rs
new file mode 100644
index 000000000..6cdc954c0
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/methods/single_char_insert_string.rs
@@ -0,0 +1,28 @@
+use super::utils::get_hint_if_single_char_arg;
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+
+use super::SINGLE_CHAR_ADD_STR;
+
+/// lint for length-1 `str`s as argument for `insert_str`
+pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, args: &[hir::Expr<'_>]) {
+    let mut applicability = Applicability::MachineApplicable;
+    if let Some(extension_string) = get_hint_if_single_char_arg(cx, &args[2], &mut applicability) {
+        let base_string_snippet =
+            snippet_with_applicability(cx, args[0].span.source_callsite(), "_", &mut applicability);
+        let pos_arg = snippet_with_applicability(cx, args[1].span, "..", &mut applicability);
+        let sugg = format!("{}.insert({}, {})", base_string_snippet, pos_arg, extension_string);
+        span_lint_and_sugg(
+            cx,
+            SINGLE_CHAR_ADD_STR,
+            expr.span,
+            "calling `insert_str()` using a single-character string literal",
+            "consider using `insert` with a character literal",
+            sugg,
+            applicability,
+        );
+    }
+}