Fix decompression CLI format detection

.github/workflows/wheel.yml

@@ -35,7 +35,7 @@ jobs:
         run: python setup.py sdist
 
       - name: Install python-snappy sdist
-        run: pip install dist/python-snappy*.tar.gz
+        run: pip install dist/python_snappy*.tar.gz
 
       - name: Pytest
         run: pytest --verbose test_snappy.py
@@ -44,26 +44,26 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: wheels
-          path: dist/python-snappy*.tar.gz
+          path: dist/python_snappy*.tar.gz
 
   build:
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-20.04, macos-12, windows-2019]
+        os: [ubuntu-22.04, macos-14, windows-2022]
         architecture: ["x64"]
         linux_archs: ["auto s390x"]
         include:
-          - os: windows-2019
+          - os: windows-2022
             architecture: "x86"
             skip: "*2*win* *win_amd64"
             environment_windows: INCLUDE="C:/Program Files (x86)/Snappy/include" LIB="C:/Program Files (x86)/Snappy/lib"
-          - os: windows-2019
+          - os: windows-2022
             architecture: "x64"
             skip: "*2*win* *win32"
             environment_windows: INCLUDE="C:/Program Files/Snappy/include" LIB="C:/Program Files/Snappy/lib"
-          - os: ubuntu-20.04
+          - os: ubuntu-22.04
             architecture: "x64"
             linux_archs: aarch64 ppc64le
 

src/snappy/__main__.py

@@ -76,13 +76,12 @@ def cmdline_main():
         method = formats.get_compress_function(args.target_format)
     else:
         try:
-            method, read_chunk = formats.get_decompress_function(
+            method = formats.get_decompress_function(
                 args.target_format,
                 args.infile
             )
         except UncompressError as err:
             sys.exit("Failed to get decompress function: {}".format(err))
-        additional_args['start_chunk'] = read_chunk
 
     method(args.infile, args.outfile, **additional_args)
 

test_formats.py

@@ -1,7 +1,9 @@
 import io
 import os
 from unittest import TestCase
-
+import subprocess
+import sys
+import tempfile
 from snappy import snappy_formats as formats
 
 
@@ -71,6 +73,58 @@ class TestFormatRawAuto(TestFormatBase):
     decompress_format = "auto"
     success = True
 
+class TestDecompressFunction(TestCase):
+    def test_auto_returns_function(self):
+        data = b"hello world"
+
+        compressed = io.BytesIO()
+        formats.get_compress_function("auto")(
+            io.BytesIO(data),
+            compressed
+        )
+        compressed.seek(0)
+
+        decompress_func = formats.get_decompress_function(
+            "auto",
+            compressed
+        )
+
+        decompressed = io.BytesIO()
+        decompress_func(compressed, decompressed)
+
+        self.assertEqual(data, decompressed.getvalue())
+
+    def test_cli_decompress(self):
+        data = b"hello world"
+
+        with tempfile.TemporaryDirectory() as tmpdir:
+            compressed = os.path.join(tmpdir, "input.snappy")
+            output = os.path.join(tmpdir, "output.txt")
+
+            with open(compressed, "wb") as f:
+                formats.get_compress_function("auto")(
+                    io.BytesIO(data),
+                    f
+                )
+
+            result = subprocess.run(
+                [
+                    sys.executable,
+                    "-m",
+                    "snappy",
+                    "-d",
+                    compressed,
+                    output,
+                ],
+                capture_output=True,
+                text=True,
+            )
+
+            self.assertEqual(result.returncode, 0)
+
+            with open(output, "rb") as f:
+                self.assertEqual(data, f.read())
+
 
 if __name__ == "__main__":
     import unittest