init

.venv/lib/python3.8/site-packages/isort/io.py

@@ -0,0 +1,73 @@
+"""Defines any IO utilities used by isort"""
+import re
+import tokenize
+from contextlib import contextmanager
+from io import BytesIO, StringIO, TextIOWrapper
+from pathlib import Path
+from typing import Any, Callable, Iterator, TextIO, Union
+
+from isort._future import dataclass
+from isort.exceptions import UnsupportedEncoding
+
+_ENCODING_PATTERN = re.compile(br"^[ \t\f]*#.*?coding[:=][ \t]*([-_.a-zA-Z0-9]+)")
+
+
+@dataclass(frozen=True)
+class File:
+    stream: TextIO
+    path: Path
+    encoding: str
+
+    @staticmethod
+    def detect_encoding(filename: Union[str, Path], readline: Callable[[], bytes]) -> str:
+        try:
+            return tokenize.detect_encoding(readline)[0]
+        except Exception:
+            raise UnsupportedEncoding(filename)
+
+    @staticmethod
+    def from_contents(contents: str, filename: str) -> "File":
+        encoding = File.detect_encoding(filename, BytesIO(contents.encode("utf-8")).readline)
+        return File(  # type: ignore
+            stream=StringIO(contents), path=Path(filename).resolve(), encoding=encoding
+        )
+
+    @property
+    def extension(self) -> str:
+        return self.path.suffix.lstrip(".")
+
+    @staticmethod
+    def _open(filename: Union[str, Path]) -> TextIOWrapper:
+        """Open a file in read only mode using the encoding detected by
+        detect_encoding().
+        """
+        buffer = open(filename, "rb")
+        try:
+            encoding = File.detect_encoding(filename, buffer.readline)
+            buffer.seek(0)
+            text = TextIOWrapper(buffer, encoding, line_buffering=True, newline="")
+            text.mode = "r"  # type: ignore
+            return text
+        except Exception:
+            buffer.close()
+            raise
+
+    @staticmethod
+    @contextmanager
+    def read(filename: Union[str, Path]) -> Iterator["File"]:
+        file_path = Path(filename).resolve()
+        stream = None
+        try:
+            stream = File._open(file_path)
+            yield File(stream=stream, path=file_path, encoding=stream.encoding)  # type: ignore
+        finally:
+            if stream is not None:
+                stream.close()
+
+
+class _EmptyIO(StringIO):
+    def write(self, *args: Any, **kwargs: Any) -> None:  # type: ignore # skipcq: PTC-W0049
+        pass
+
+
+Empty = _EmptyIO()