fix validation of ints with leading unary minus (#1291)

Author: RajatRajdeep

src/input/shared.rs

@@ -114,8 +114,13 @@ fn clean_int_str(mut s: &str) -> Option<Cow<str>> {
     // strip leading and trailing whitespace
     s = s.trim();
 
-    // strip leading unary plus
-    s = s.strip_prefix('+').unwrap_or(s);
+    // Check for and remove a leading unary plus and ensure the next character is not a unary minus. e.g.: '+-1'.
+    if let Some(suffix) = s.strip_prefix('+') {
+        if suffix.starts_with('-') {
+            return None;
+        }
+        s = suffix;
+    }
 
     // strip loading zeros
     s = strip_leading_zeros(s)?;
@@ -149,17 +154,17 @@ fn strip_leading_zeros(s: &str) -> Option<&str> {
     match char_iter.next() {
         // if we get a leading zero we continue
         Some((_, '0')) => (),
-        // if we get another digit we return the whole string
-        Some((_, c)) if ('1'..='9').contains(&c) => return Some(s),
+        // if we get another digit or unary minus we return the whole string
+        Some((_, c)) if ('1'..='9').contains(&c) || c == '-' => return Some(s),
         // anything else is invalid, we return None
         _ => return None,
     };
     for (i, c) in char_iter {
         match c {
             // continue on more leading zeros or if we get an underscore we continue - we're "within the number"
             '0' | '_' => (),
-            // any other digit we return the rest of the string
-            '1'..='9' => return Some(&s[i..]),
+            // any other digit or unary minus we return the rest of the string
+            '1'..='9' | '-' => return Some(&s[i..]),
             // if we get a dot we return the rest of the string but include the last zero
             '.' => return Some(&s[(i - 1)..]),
             // anything else is invalid, we return None

tests/validators/test_int.py

@@ -29,6 +29,8 @@
         ('+0_000', 0),
         (1, 1),
         ('  1  ', 1),
+        ('-1', -1),
+        ('-1.0', -1),
         (42, 42),
         ('42', 42),
         (42.0, 42),
@@ -48,6 +50,7 @@
         ('+4_2.0', 42),
         ('+04_2.0', 42),
         ('++4_2', Err('Input should be a valid integer, unable to parse string as an integer')),
+        ('-+1', Err('Input should be a valid integer, unable to parse string as an integer')),
         ('+-1', Err('Input should be a valid integer, unable to parse string as an integer')),
         ('4_2', 42),
         ('0_42', 42),