Enable assigning a Number to java.lang.Character

Use coerceToNumber when JS Type is numeric and target type is java.lang.Character. This lets you assign a JavaScript number to a java.lang.Character without triggering an exception.

rhino/src/main/java/org/mozilla/javascript/NativeJavaObject.java

@@ -534,7 +534,8 @@ static Object coerceTypeImpl(Class<?> type, Object value) {
                     return coerceToNumber(
                             jsTypeCode == JSTYPE_BIGINT ? BigInteger.class : Double.TYPE, value);
                 } else if ((type.isPrimitive() && type != Boolean.TYPE)
-                        || ScriptRuntime.NumberClass.isAssignableFrom(type)) {
+                        || ScriptRuntime.NumberClass.isAssignableFrom(type)
+                        || ScriptRuntime.CharacterClass.isAssignableFrom(type)) {
                     return coerceToNumber(type, value);
                 } else {
                     reportConversionError(value, type);

tests/src/test/java/org/mozilla/javascript/tests/CharacterAssignmentTest.java

@@ -0,0 +1,50 @@
+package org.mozilla.javascript.tests;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.Test;
+import org.mozilla.javascript.tools.shell.Global;
+
+/**
+ * @author Jakob Silbereisen, Foconis Analytics GmbH
+ */
+public class CharacterAssignmentTest {
+
+    public static class X {
+        public Character bigCharacter;
+        public char primitiveCharacter;
+
+        public X() {}
+
+        public X(char c) {
+            bigCharacter = c;
+            primitiveCharacter = c;
+        }
+    }
+
+    @Test
+    public void assignCharacterTypesFromNumbers() {
+        Utils.runWithAllModes(
+                cx -> {
+                    final Global scope = new Global();
+                    scope.init(cx);
+                    X x1 = new X(), x2 = new X();
+                    scope.put("x1", scope, x1);
+                    scope.put("x2", scope, x2);
+                    scope.put("src", scope, new X('X'));
+                    Object ret =
+                            cx.evaluateString(
+                                    scope,
+                                    "x1.bigCharacter = 65;"
+                                            + "x1.primitiveCharacter = 65;"
+                                            + "x2.bigCharacter = src.primitiveCharacter;",
+                                    "myScript.js",
+                                    1,
+                                    null);
+                    assertEquals('A', x1.bigCharacter);
+                    assertEquals('A', x1.primitiveCharacter);
+                    assertEquals('X', x2.bigCharacter);
+                    return null;
+                });
+    }
+}