[Form] NumberType: Fix parsing of numbers in exponential notation with negative exponent

Author: jbtronics

Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php

@@ -143,7 +143,8 @@ public function reverseTransform($value)
             $value = str_replace(',', $decSep, $value);
         }
 
-        if (str_contains($value, $decSep)) {
+        //If the value is in exponential notation with a negative exponent, we end up with a float value too
+        if (str_contains($value, $decSep) || false !== stripos($value, 'e-')) {
             $type = \NumberFormatter::TYPE_DOUBLE;
         } else {
             $type = \PHP_INT_SIZE === 8

Tests/Extension/Core/DataTransformer/NumberToLocalizedStringTransformerTest.php

@@ -632,4 +632,31 @@ public function testReverseTransformSmallInt()
 
         $this->assertSame(1.0, $transformer->reverseTransform('1'));
     }
+
+    /**
+     * @dataProvider eNotationProvider
+     */
+    public function testReverseTransformENotation($output, $input)
+    {
+        \Locale::setDefault('en');
+
+        $transformer = new NumberToLocalizedStringTransformer();
+
+        $this->assertSame($output, $transformer->reverseTransform($input));
+    }
+
+    public static function eNotationProvider(): array
+    {
+        return [
+            [0.001, '1E-3'],
+            [0.001, '1.0E-3'],
+            [0.001, '1e-3'],
+            [0.001, '1.0e-03'],
+            [1000.0, '1E3'],
+            [1000.0, '1.0E3'],
+            [1000.0, '1e3'],
+            [1000.0, '1.0e3'],
+            [1232.0, '1.232e3'],
+        ];
+    }
 }