src/tools/clippy/clippy_lints/src/misc_early/zero_prefixed_literal.rs

   1 use clippy_utils::diagnostics::span_lint_and_then;
   2 use rustc_errors::Applicability;
   3 use rustc_lint::EarlyContext;
   4 use rustc_span::Span;
   5
   6 use super::ZERO_PREFIXED_LITERAL;
   7
   8 pub(super) fn check(cx: &EarlyContext<'_>, lit_span: Span, lit_snip: &str) {
   9     let trimmed_lit_snip = lit_snip.trim_start_matches(|c| c == '_' || c == '0');
  10     span_lint_and_then(
  11         cx,
  12         ZERO_PREFIXED_LITERAL,
  13         lit_span,
  14         "this is a decimal constant",
  15         |diag| {
  16             diag.span_suggestion(
  17                 lit_span,
  18                 "if you mean to use a decimal constant, remove the `0` to avoid confusion",
  19                 trimmed_lit_snip.to_string(),
  20                 Applicability::MaybeIncorrect,
  21             );
  22             // do not advise to use octal form if the literal cannot be expressed in base 8.
  23             if !lit_snip.contains(|c| c == '8' || c == '9') {
  24                 diag.span_suggestion(
  25                     lit_span,
  26                     "if you mean to use an octal constant, use `0o`",
  27                     format!("0o{trimmed_lit_snip}"),
  28                     Applicability::MaybeIncorrect,
  29                 );
  30             }
  31         },
  32     );
  33 }