diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/methods/single_char_insert_string.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/methods/single_char_insert_string.rs | 28 |
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, + ); + } +} |