fix(cli): only consume --black-box value when it is a directory

cobol_testgen/__init__.py

@@ -1391,6 +1391,41 @@ def _inject_c01_coverage_records(records, fields, base_assignments):
 
 # ── 入口 ──
 
+def _extract_black_box_args(args: list) -> tuple[bool, str | None]:
+    """就地解析 --black-box / --no-black-box，返回 (do_black_box, black_box_arg)。
+
+    `--black-box <dir>`：仅当后一个 token 是「已存在的目录」且非 COBOL 源码后缀时
+    才消费为目录；否则视为裸 `--black-box`（自动探测 <outdir>/<PGM>/black_box）。
+    """
+    do_black_box = False
+    black_box_arg = None
+    i = 0
+    while i < len(args):
+        a = args[i]
+        if a == '--no-black-box':
+            do_black_box = False
+            args.pop(i)
+            continue
+        if a == '--black-box':
+            do_black_box = True
+            if i + 1 < len(args):
+                nxt = args[i + 1]
+                if (not nxt.startswith('--')
+                        and Path(nxt).is_dir()
+                        and Path(nxt).suffix.upper() not in ('.CBL', '.COB', '.CPY')):
+                    black_box_arg = nxt
+                    args.pop(i + 1)
+            args.pop(i)
+            continue
+        if a.startswith('--black-box='):
+            do_black_box = True
+            black_box_arg = a.split('=', 1)[1]
+            args.pop(i)
+            continue
+        i += 1
+    return do_black_box, black_box_arg
+
+
 def main():
     if len(sys.argv) < 2:
         print("用法: python -m cobol_testgen <cobol文件1> [cobol文件2 ...] [输出目录]")
@@ -1411,28 +1446,7 @@ def main():
             logger.warning("--gcov: runner.py not found. Compile/run will be skipped. "
                            "Use --gcov without runner only generates test data + static coverage.")
 
-    do_black_box = False
-    black_box_arg = None
-    i = 0
-    while i < len(args):
-        a = args[i]
-        if a == '--no-black-box':
-            do_black_box = False
-            args.pop(i)
-            continue
-        if a == '--black-box':
-            do_black_box = True
-            if i + 1 < len(args) and not args[i + 1].startswith('--'):
-                black_box_arg = args[i + 1]
-                args.pop(i + 1)
-            args.pop(i)
-            continue
-        if a.startswith('--black-box='):
-            do_black_box = True
-            black_box_arg = a.split('=', 1)[1]
-            args.pop(i)
-            continue
-        i += 1
+    do_black_box, black_box_arg = _extract_black_box_args(args)
 
     i = 0
     while i < len(args):

tests/cobol_testgen/test_cli_blackbox.py

@@ -0,0 +1,50 @@
+"""cobol_testgen --black-box CLI 参数解析测试"""
+
+import os
+import sys
+
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..")))
+
+from cobol_testgen import _extract_black_box_args
+
+
+def test_black_box_dir_consumed(tmp_path):
+    d = tmp_path / "prog"
+    d.mkdir()
+    args = ["--black-box", str(d), "src.cbl", "out"]
+    do, arg = _extract_black_box_args(args)
+    assert do is True
+    assert arg == str(d)
+    assert args == ["src.cbl", "out"]
+
+
+def test_black_box_bare_does_not_consume_source():
+    args = ["--black-box", "src.cbl", "out"]
+    do, arg = _extract_black_box_args(args)
+    assert do is True
+    assert arg is None
+    assert args == ["src.cbl", "out"]
+
+
+def test_black_box_equals_form():
+    args = ["--black-box=bbdir", "src.cbl"]
+    do, arg = _extract_black_box_args(args)
+    assert do is True
+    assert arg == "bbdir"
+    assert args == ["src.cbl"]
+
+
+def test_no_black_box():
+    args = ["--no-black-box", "src.cbl"]
+    do, arg = _extract_black_box_args(args)
+    assert do is False
+    assert arg is None
+    assert args == ["src.cbl"]
+
+
+def test_no_flags_leaves_args_untouched():
+    args = ["src.cbl", "out"]
+    do, arg = _extract_black_box_args(args)
+    assert do is False
+    assert arg is None
+    assert args == ["src.cbl", "out"]