phase3: nullfix arg-bang handler (argument_type/invalid_assignment). 872 -> 621

tools/nullfix.py

@@ -101,6 +101,29 @@ def insert_bang(line, col0, name, kind):
         return None
     return None
 
+def insert_arg_bang(line, col0):
+    """在参数值末尾插 '!'（仅限简单值：标识符/成员/调用/下标）。"""
+    depth=0; end=None
+    for i in range(col0, len(line)):
+        ch=line[i]
+        if ch in '([{': depth+=1
+        elif ch in ')]}':
+            if depth==0: end=i; break
+            depth-=1
+        elif ch==',' and depth==0: end=i; break
+    if end is None: end=len(line)
+    # 值的实际末尾（跳过空白）
+    j=end-1
+    while j>=col0 and line[j] in ' \t': j-=1
+    if j<col0: return None
+    if line[j]=='!': return None
+    val=line[col0:j+1].strip()
+    if not val: return None
+    if val[0] in '0123456789"\'': return None      # 字面量跳过
+    if val in ('true','false','null'): return None
+    if not re.fullmatch(r'[\w.\[\]()]+', val): return None  # 含运算符等跳过
+    return line[:j+1]+'!'+line[j+1:]
+
 def make_field_nullable(lines, name):
     """找字段声明 'Type name;' 并在类型后加 '?'。返回 (行索引, 新行) 或 (None,None)。"""
     pat = re.compile(r'^(\s+(?:final\s+|const\s+)?(?:static\s+)?)(.+)\s+'+re.escape(name)+r';\s*$')
@@ -170,6 +193,8 @@ def apply_round(errs):
                     new=insert_nullable_before_name(old, pname, col-1)
         elif rule in ('not_initialized_non_nullable_instance_field','not_initialized_non_nullable_variable'):
             new=insert_late(old)
+        elif rule in ('argument_type_not_assignable','invalid_assignment'):
+            new=insert_arg_bang(old, col-1)
         if new and new!=old:
             L[line-1]=new; changed+=1
     flush()