Handle unicode minus character when parsing floats

crates/egui/src/widgets/drag_value.rs

@@ -677,8 +677,14 @@ fn parse(custom_parser: &Option<NumParser<'_>>, value_text: &str) -> Option<f64>
 }
 
 fn default_parser(value_text: &str) -> Option<f64> {
+    let value_text: String = value_text
+        .chars()
         // Ignore whitespace (trailing, leading, and thousands separators):
-    let value_text: String = value_text.chars().filter(|c| !c.is_whitespace()).collect();
+        .filter(|c| !c.is_whitespace())
+        // Replace special minus character with normal minus (hyphen):
+        .map(|c| if c == '−' { '-' } else { c })
+        .collect();
+
     value_text.parse().ok()
 }
 
@@ -744,5 +750,16 @@ mod tests {
             Some(1_234_567.0),
             "We should handle thousands separators using half-space"
         );
+
+        assert_eq!(
+            super::default_parser("-1.23"),
+            Some(-1.23),
+            "Should handle normal hyphen as minus character"
+        );
+        assert_eq!(
+            super::default_parser("−1.23"),
+            Some(-1.23),
+            "Should handle special minus character (https://www.compart.com/en/unicode/U+2212)"
+        );
     }
 }