Make ".e0" not parse as 0.0

This forces floats to have either a digit before the separating point, or after. Thus ".e0" is invalid like ".", when using `parse()`.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/libcore/tests/num/dec2flt/mod.rs b/src/libcore/tests/num/dec2flt/mod.rs
index 9934e1dab96..17b2f59cd4d 100644
--- a/src/libcore/tests/num/dec2flt/mod.rs
+++ b/src/libcore/tests/num/dec2flt/mod.rs
@@ -102,6 +102,12 @@ fn lonely_dot() {
 }
 
 #[test]
+fn exponentiated_dot() {
+    assert!(".e0".parse::<f32>().is_err());
+    assert!(".e0".parse::<f64>().is_err());
+}
+
+#[test]
 fn lonely_sign() {
     assert!("+".parse::<f32>().is_err());
     assert!("-".parse::<f64>().is_err());