}
fn check_missing_else(cx: &EarlyContext<'_>, first: &Expr, second: &Expr) {
- if !differing_macro_contexts(first.span, second.span)
- && !first.span.from_expansion()
- && is_if(first)
- && (is_block(second) || is_if(second))
- {
- // where the else would be
- let else_span = first.span.between(second.span);
+ if_chain! {
+ if !differing_macro_contexts(first.span, second.span);
+ if !first.span.from_expansion();
+ if let ExprKind::If(cond_expr, ..) = &first.kind;
+ if is_block(second) || is_if(second);
- if let Some(else_snippet) = snippet_opt(cx, else_span) {
- if !else_snippet.contains('\n') {
- let (looks_like, next_thing) = if is_if(second) {
- ("an `else if`", "the second `if`")
- } else {
- ("an `else {..}`", "the next block")
- };
+ // Proc-macros can give weird spans. Make sure this is actually an `if`.
+ if let Some(if_snip) = snippet_opt(cx, first.span.until(cond_expr.span));
+ if if_snip.starts_with("if");
- span_lint_and_note(
- cx,
- SUSPICIOUS_ELSE_FORMATTING,
- else_span,
- &format!("this looks like {} but the `else` is missing", looks_like),
- None,
- &format!(
- "to remove this lint, add the missing `else` or add a new line before {}",
- next_thing,
- ),
- );
- }
+ // If there is a line break between the two expressions, don't lint.
+ // If there is a non-whitespace character, this span came from a proc-macro.
+ let else_span = first.span.between(second.span);
+ if let Some(else_snippet) = snippet_opt(cx, else_span);
+ if !else_snippet.chars().any(|c| c == '\n' || !c.is_whitespace());
+ then {
+ let (looks_like, next_thing) = if is_if(second) {
+ ("an `else if`", "the second `if`")
+ } else {
+ ("an `else {..}`", "the next block")
+ };
+
+ span_lint_and_note(
+ cx,
+ SUSPICIOUS_ELSE_FORMATTING,
+ else_span,
+ &format!("this looks like {} but the `else` is missing", looks_like),
+ None,
+ &format!(
+ "to remove this lint, add the missing `else` or add a new line before {}",
+ next_thing,
+ ),
+ );
}
}
}