feat(license): apply() for Bash with shebang-aware placement (ref #81)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/license-headers.py

@@ -48,6 +48,7 @@ def render_header(style: str) -> str:
 
 LANG_TABLE: dict[str, tuple[str, str]] = {
     ".py": ("hash", "python"),
+    ".sh": ("hash", "shebang_hash"),
 }
 
 
@@ -63,8 +64,16 @@ def _place_python(header: str, text: str) -> str:
     return "".join(lines[:insert_at]) + header + "\n" + "".join(lines[insert_at:])
 
 
+def _place_shebang_hash(header: str, text: str) -> str:
+    """Hash-comment language with a shebang line on line 1."""
+    lines = text.splitlines(keepends=True)
+    insert_at = 1 if lines and lines[0].startswith("#!") else 0
+    return "".join(lines[:insert_at]) + header + "\n" + "".join(lines[insert_at:])
+
+
 _PLACERS = {
     "python": _place_python,
+    "shebang_hash": _place_shebang_hash,
 }
 
 

tests/test_license_headers.py

@@ -155,3 +155,23 @@ def test_apply_python_with_shebang_and_encoding():
     assert lines[0] == "#!/usr/bin/env python3"
     assert lines[1] == "# -*- coding: utf-8 -*-"
     assert lines[2] == "# SPDX-License-Identifier: LicenseRef-CMSD-1.0"
+
+
+def test_apply_bash_with_shebang():
+    src = '#!/usr/bin/env bash\nset -euo pipefail\necho "hi"\n'
+    out = license_headers.apply(src, ".sh")
+    assert out.startswith("#!/usr/bin/env bash\n")
+    assert out.splitlines()[1] == "# SPDX-License-Identifier: LicenseRef-CMSD-1.0"
+
+
+def test_apply_bash_without_shebang():
+    src = 'echo "hi"\n'
+    out = license_headers.apply(src, ".sh")
+    assert out.startswith("# SPDX-License-Identifier: LicenseRef-CMSD-1.0\n")
+
+
+def test_apply_bash_idempotent():
+    src = '#!/usr/bin/env bash\nset -e\n'
+    once = license_headers.apply(src, ".sh")
+    twice = license_headers.apply(once, ".sh")
+    assert once == twice