Change argument checking in SoundFile.__init__()

pysoundfile.py

@@ -334,43 +334,18 @@ def __init__(self, file, mode='r', samplerate=None, channels=None,
         except KeyError:
             raise ValueError("Invalid mode: %s" % repr(mode))
 
-        original_format = format
-        filename = getattr(file, 'name', file)
-        file_extension = str(filename).rsplit('.', 1)[-1].upper()
-        if format is None and ('w' in self.mode or
-                               file_extension == 'RAW'):
-            if file_extension not in _formats:
-                if self.mode == 'w':
-                    raise TypeError(
-                        "No format specified and unable to get format from "
-                        "file extension: %s" % repr(filename))
-            else:
-                format = file_extension
+        if format is None:
+            ext = str(getattr(file, 'name', file)).rsplit('.', 1)[-1].upper()
+            if ext in _formats:
+                format = ext
 
         self._info = _ffi.new("SF_INFO*")
-        if self.mode == 'w' or str(format).upper() == 'RAW':
-            if samplerate is None:
-                raise TypeError("samplerate must be specified")
+        if samplerate is not None:
             self._info.samplerate = samplerate
-            if channels is None:
-                raise TypeError("channels must be specified")
+        if channels is not None:
             self._info.channels = channels
-            if str(format).upper() == 'RAW' and subtype is None:
-                raise TypeError("RAW files must specify a subtype")
+        if format is not None:
             self._info.format = _format_int(format, subtype, endian)
-        elif self.mode == 'rw':
-            if samplerate is not None:
-                self._info.samplerate = samplerate
-            if channels is not None:
-                self._info.channels = channels
-            if format is not None:
-                self._info.format = _format_int(format, subtype, endian)
-        else:
-            if [samplerate, channels, original_format, subtype, endian] != \
-                    [None] * 5:
-                raise TypeError("Only allowed if mode='w' or format='RAW': "
-                                "samplerate, channels, "
-                                "format, subtype, endian")
 
         self._name = file
         if isinstance(file, str):
@@ -383,10 +358,23 @@ def __init__(self, file, mode='r', samplerate=None, channels=None,
                 self._init_virtual_io(file), mode_int, self._info, _ffi.NULL)
             self._name = str(file)
         else:
-            raise RuntimeError("file must be a filename, a file descriptor or "
-                               "a file-like object with the methods "
-                               "'seek()', 'read()', 'write()' and 'tell()'")
-        self._handle_error()
+            raise TypeError("Invalid file: %s" % repr(file))
+
+        err = _snd.sf_error(self._file)
+        if err != 0 and (self.mode != 'r' or self.format == 'RAW'):
+            missing = []
+            if self._info.samplerate == 0:
+                missing.append("samplerate")
+            if self._info.channels == 0:
+                missing.append("channels")
+            if self._info.format & _snd.SF_FORMAT_TYPEMASK == 0:
+                missing.append("format")
+            if missing:
+                raise RuntimeError(
+                    "Error opening %r. Missing %s? (libsndfile: %s)" % (
+                        self.name, "/".join(missing),
+                        _ffi.string(_snd.sf_error_number(err)).decode()))
+        self._handle_error_number(err)
 
     name = property(lambda self: self._name)
     mode = property(lambda self: self._mode)
@@ -502,9 +490,6 @@ def __setattr__(self, name, value):
         # access text data in the sound file through properties
         if name in _str_types:
             self._check_if_closed()
-            if self.mode == 'r':
-                raise RuntimeError("Can not change %s of file in read mode" %
-                                   repr(name))
             data = _ffi.new('char[]', value.encode())
             err = _snd.sf_set_string(self._file, _str_types[name], data)
             self._handle_error_number(err)
@@ -557,8 +542,6 @@ def __setitem__(self, frame, data):
         # access the file as if it where a one-dimensional Numpy
         # array. Data must be in the form (frames x channels).
         # Both open slice bounds and negative values are allowed.
-        if self.mode == 'r':
-            raise RuntimeError("Cannot write to file opened in read mode")
         start, stop = self._get_slice_bounds(frame)
         if stop - start != len(data):
             raise IndexError(
@@ -634,6 +617,7 @@ def _create_empty_array(self, frames, always_2d, dtype):
 
     def _read_or_write(self, funcname, array, frames):
         # Call into libsndfile
+        self._check_if_closed()
         ffi_type = _ffi_types[array.dtype]
         assert array.flags.c_contiguous
         assert array.dtype.itemsize == _ffi.sizeof(ffi_type)
@@ -671,7 +655,6 @@ def read(self, frames=-1, dtype='float64', always_2d=True,
         containing all valid frames is returned.
 
         """
-        self._check_if_closed()
         if self.mode == 'w':
             raise RuntimeError("Cannot read from file opened in write mode")
 
@@ -709,7 +692,6 @@ def write(self, data):
         array or as one-dimensional array for mono signals.
 
         """
-        self._check_if_closed()
         if self.mode == 'r':
             raise RuntimeError("Cannot write to file opened in read mode")
 

tests/test_pysoundfile.py

@@ -312,6 +312,59 @@ def test_blocks_write(sf_stereo_w):
         list(sf_stereo_w.blocks(blocksize=2))
 
 
+# -----------------------------------------------------------------------------
+# Test open()
+# -----------------------------------------------------------------------------
+
+
+def test_open_with_invalid_file():
+    with pytest.raises(TypeError) as excinfo:
+        sf.open(3.1415)
+    assert "Invalid file" in str(excinfo.value)
+
+
+def test_open_with_invalid_mode():
+    with pytest.raises(ValueError) as excinfo:
+        sf.open(filename_stereo, 42)
+    assert "Invalid mode" in str(excinfo.value)
+    with pytest.raises(ValueError) as excinfo:
+        sf.open(filename_stereo, 'wr')
+    assert "Invalid mode" in str(excinfo.value)
+
+
+def test_open_with_more_invalid_arguments():
+    with pytest.raises(TypeError) as excinfo:
+        sf.open(filename_new, 'w', samplerate=3.1415, channels=2)
+    assert "integer" in str(excinfo.value)
+    with pytest.raises(TypeError) as excinfo:
+        sf.open(filename_new, 'w', samplerate=44100, channels=3.1415)
+    assert "integer" in str(excinfo.value)
+    with pytest.raises(ValueError) as excinfo:
+        sf.open(filename_new, 'w', 44100, 2, format='WAF')
+    assert "Invalid format string" in str(excinfo.value)
+    with pytest.raises(ValueError) as excinfo:
+        sf.open(filename_new, 'w', 44100, 2, subtype='PCM16')
+    assert "Invalid subtype string" in str(excinfo.value)
+    with pytest.raises(ValueError) as excinfo:
+        sf.open(filename_new, 'w', 44100, 2, endian='BOTH')
+    assert "Invalid endian-ness" in str(excinfo.value)
+
+
+def test_open_w_and_rw_new_with_too_few_arguments(tmpdir):
+    with tmpdir.as_cwd():
+        filename = 'not_existing.xyz'
+        for mode in 'w', 'rw':
+            with pytest.raises(RuntimeError) as excinfo:
+                sf.open(filename, mode, samplerate=44100, channels=2)
+            assert "Missing format" in str(excinfo.value)
+            with pytest.raises(RuntimeError) as excinfo:
+                sf.open(filename, mode, samplerate=44100, format='WAV')
+            assert "channels" in str(excinfo.value)
+            with pytest.raises(RuntimeError) as excinfo:
+                sf.open(filename, mode, channels=2, format='WAV')
+            assert "samplerate" in str(excinfo.value)
+
+
 # -----------------------------------------------------------------------------
 # Test file metadata
 # -----------------------------------------------------------------------------
@@ -548,17 +601,20 @@ def test_non_file_attributes_should_not_save_to_disk():
 
 
 def test_read_raw_files_should_read_data():
-    with sf.open(filename_raw, samplerate=44100,
-                 channels=1, subtype='PCM_16') as f:
+    with sf.open(filename_raw, 'r', 44100, 1, 'PCM_16') as f:
         assert np.all(f.read(dtype='int16') == data_mono)
 
 
 def test_read_raw_files_with_too_few_arguments_should_fail():
-    with pytest.raises(TypeError):  # missing everything
+    with pytest.raises(TypeError) as excinfo:  # missing everything
         sf.open(filename_raw)
-    with pytest.raises(TypeError):  # missing subtype
+    assert "No default subtype" in str(excinfo.value)
+    with pytest.raises(TypeError) as excinfo:  # missing subtype
         sf.open(filename_raw, samplerate=44100, channels=2)
-    with pytest.raises(TypeError):  # missing channels
+    assert "No default subtype" in str(excinfo.value)
+    with pytest.raises(RuntimeError) as excinfo:  # missing channels
         sf.open(filename_raw, samplerate=44100, subtype='PCM_16')
-    with pytest.raises(TypeError):  # missing samplerate
+    assert "channels" in str(excinfo.value)
+    with pytest.raises(RuntimeError) as excinfo:  # missing samplerate
         sf.open(filename_raw, channels=2, subtype='PCM_16')
+    assert "samplerate" in str(excinfo.value)