Merge pull request #111 from pycompression/noname

Add --no-name flag.

Author: rhpvorderman

CHANGELOG.rst

@@ -22,6 +22,7 @@ that PyPy is no longer supported.
   for decompressing gzip files. PyPy should not be used for workloads that
   require heavy zlib-compatible compression/decompression. As such it was
   deemed unnecessary to continue supporting PyPy.
++ A ``--no-name`` flag has been added to ``python -m isal.igzip``.
 + Cython is no longer required as a build dependency.
 + a fast function calling method ``METH_FASTCALL`` is now used to call the
   functions. This method is only  supported by Python 3.7 and higher. This has

src/isal/igzip.py

@@ -442,6 +442,10 @@ def _argument_parser():
                               help="write on standard output")
     output_group.add_argument("-o", "--output",
                               help="Write to this output file")
+    parser.add_argument("-n", "--no-name", action="store_true",
+                        dest="reproducible",
+                        help="do not save or restore the original name and "
+                             "timestamp")
     parser.add_argument("-f", "--force", action="store_true",
                         help="Overwrite output without prompting")
     # -b flag not taken by either gzip or igzip. Hidden attribute. Above 32K
@@ -485,10 +489,16 @@ def main():
         else:
             in_file = io.open(args.file, mode="rb")
         if out_filepath is not None:
-            out_file = open(out_filepath, "wb", compresslevel=compresslevel)
+            out_buffer = io.open(out_filepath, "wb")
         else:
-            out_file = IGzipFile(mode="wb", fileobj=sys.stdout.buffer,
-                                 compresslevel=compresslevel)
+            out_buffer = sys.stdout.buffer
+
+        if args.reproducible:
+            gzip_file_kwargs = {"mtime": 0, "filename": b""}
+        else:
+            gzip_file_kwargs = {"filename": out_filepath}
+        out_file = IGzipFile(mode="wb", fileobj=out_buffer,
+                             compresslevel=compresslevel, **gzip_file_kwargs)
     else:
         if args.file:
             in_file = open(args.file, mode="rb")

tests/test_igzip.py

@@ -222,6 +222,21 @@ def test_compress_infile_out_file_inmplicit_name_prompt_accept(
     assert err == b""
 
 
+def test_compress_infile_out_file_no_name(tmp_path, capsysbinary):
+    test = tmp_path / "test"
+    test.write_bytes(DATA)
+    out_file = tmp_path / "compressed.gz"
+    sys.argv = ['', '-n', '-o', str(out_file), str(test)]
+    igzip.main()
+    out, err = capsysbinary.readouterr()
+    output = out_file.read_bytes()
+    assert gzip.decompress(output) == DATA
+    assert err == b''
+    assert out == b''
+    assert output[4] & gzip.FNAME == 0  # No filename set.
+    assert output[4:8] == b"\x00\x00\x00\x00"  # No timestamp set.
+
+
 def test_decompress():
     assert igzip.decompress(COMPRESSED_DATA) == DATA