Correctly handle signs in exponents in numeric_literal::format()

[rust.git] / clippy_utils / src / numeric_literal.rs

diff --git a/clippy_utils/src/numeric_literal.rs b/clippy_utils/src/numeric_literal.rs
index d02603d7702c7f3c6a8f7f48d30b29a027ff7e00..98f65039b7da9fb2765e72d7a6f6e44bd8ab077f 100644 (file)
--- a/clippy_utils/src/numeric_literal.rs
+++ b/clippy_utils/src/numeric_literal.rs
@@ -1,4 +1,5 @@
 use rustc_ast::ast::{Lit, LitFloatType, LitIntType, LitKind};
+use std::iter;
 
 #[derive(Debug, PartialEq, Copy, Clone)]
 pub enum Radix {
@@ -51,7 +52,7 @@ pub fn from_lit(src: &'a str, lit: &Lit) -> Option<NumericLiteral<'a>> {
 
     pub fn from_lit_kind(src: &'a str, lit_kind: &LitKind) -> Option<NumericLiteral<'a>> {
         if lit_kind.is_numeric() && src.chars().next().map_or(false, |c| c.is_digit(10)) {
-            let (unsuffixed, suffix) = split_suffix(&src, lit_kind);
+            let (unsuffixed, suffix) = split_suffix(src, lit_kind);
             let float = matches!(lit_kind, LitKind::Float(..));
             Some(NumericLiteral::new(unsuffixed, suffix, float))
         } else {
@@ -161,6 +162,9 @@ pub fn format(&self) -> String {
         }
 
         if let Some(suffix) = self.suffix {
+            if output.ends_with('.') {
+                output.push('0');
+            }
             output.push('_');
             output.push_str(suffix);
         }
@@ -173,6 +177,13 @@ pub fn group_digits(output: &mut String, input: &str, group_size: usize, partial
 
         let mut digits = input.chars().filter(|&c| c != '_');
 
+        // The exponent may have a sign, output it early, otherwise it will be
+        // treated as a digit
+        if let Some('-') = digits.clone().next() {
+            let _ = digits.next();
+            output.push('-');
+        }
+
         let first_group_size;
 
         if partial_group_first {
@@ -192,7 +203,7 @@ pub fn group_digits(output: &mut String, input: &str, group_size: usize, partial
             }
         }
 
-        for (c, i) in digits.zip((0..group_size).cycle()) {
+        for (c, i) in iter::zip(digits, (0..group_size).cycle()) {
             if i == 0 {
                 output.push('_');
             }