Merge pull request #1268 from nschloe/double-filetypes

Double filetypes

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = meshio
-version = 5.2.6
+version = 5.3.0
 author = Nico Schlömer et al.
 author_email = nico.schloemer@gmail.com
 description = I/O for many mesh formats

src/meshio/__init__.py

@@ -34,7 +34,8 @@
 from .__about__ import __version__
 from ._exceptions import ReadError, WriteError
 from ._helpers import (
-    extension_to_filetype,
+    deregister_format,
+    extension_to_filetypes,
     read,
     register_format,
     write,
@@ -77,8 +78,9 @@
     "read",
     "write",
     "register_format",
+    "deregister_format",
     "write_points_cells",
-    "extension_to_filetype",
+    "extension_to_filetypes",
     "Mesh",
     "CellBlock",
     "ReadError",

src/meshio/_cli/_ascii.py

@@ -3,7 +3,7 @@
 
 from .. import ansys, flac3d, gmsh, mdpa, ply, stl, vtk, vtu, xdmf
 from .._common import error
-from .._helpers import _filetype_from_path, read, reader_map
+from .._helpers import _filetypes_from_path, read, reader_map
 
 
 def add_args(parser):
@@ -20,8 +20,12 @@ def add_args(parser):
 
 
 def ascii(args):
-    # read mesh data
-    fmt = args.input_format or _filetype_from_path(pathlib.Path(args.infile))
+    if args.input_format:
+        fmts = [args.input_format]
+    else:
+        fmts = _filetypes_from_path(pathlib.Path(args.infile))
+    # pick the first
+    fmt = fmts[0]
 
     size = os.stat(args.infile).st_size
     print(f"File size before: {size / 1024 ** 2:.2f} MB")

src/meshio/_cli/_binary.py

@@ -2,7 +2,7 @@
 import pathlib
 
 from .. import ansys, flac3d, gmsh, mdpa, ply, stl, vtk, vtu, xdmf
-from .._helpers import _filetype_from_path, read, reader_map
+from .._helpers import _filetypes_from_path, read, reader_map
 
 
 def add_args(parser):
@@ -19,8 +19,12 @@ def add_args(parser):
 
 
 def binary(args):
-    # read mesh data
-    fmt = args.input_format or _filetype_from_path(pathlib.Path(args.infile))
+    if args.input_format:
+        fmts = [args.input_format]
+    else:
+        fmts = _filetypes_from_path(pathlib.Path(args.infile))
+    # pick the first
+    fmt = fmts[0]
 
     size = os.stat(args.infile).st_size
     print(f"File size before: {size / 1024 ** 2:.2f} MB")

src/meshio/_cli/_compress.py

@@ -3,7 +3,7 @@
 
 from .. import ansys, cgns, gmsh, h5m, mdpa, ply, stl, vtk, vtu, xdmf
 from .._common import error
-from .._helpers import _filetype_from_path, read, reader_map
+from .._helpers import _filetypes_from_path, read, reader_map
 
 
 def add_args(parser):
@@ -26,8 +26,12 @@ def add_args(parser):
 
 
 def compress(args):
-    # read mesh data
-    fmt = args.input_format or _filetype_from_path(pathlib.Path(args.infile))
+    if args.input_format:
+        fmts = [args.input_format]
+    else:
+        fmts = _filetypes_from_path(pathlib.Path(args.infile))
+    # pick the first
+    fmt = fmts[0]
 
     size = os.stat(args.infile).st_size
     print(f"File size before: {size / 1024 ** 2:.2f} MB")

src/meshio/_cli/_decompress.py

@@ -3,7 +3,7 @@
 
 from .. import cgns, h5m, vtu, xdmf
 from .._common import error
-from .._helpers import _filetype_from_path, read, reader_map
+from .._helpers import _filetypes_from_path, read, reader_map
 
 
 def add_args(parser):
@@ -19,8 +19,12 @@ def add_args(parser):
 
 
 def decompress(args):
-    # read mesh data
-    fmt = args.input_format or _filetype_from_path(pathlib.Path(args.infile))
+    if args.input_format:
+        fmts = [args.input_format]
+    else:
+        fmts = _filetypes_from_path(pathlib.Path(args.infile))
+    # pick the first
+    fmt = fmts[0]
 
     size = os.stat(args.infile).st_size
     print(f"File size before: {size / 1024 ** 2:.2f} MB")

src/meshio/_helpers.py

@@ -1,39 +1,59 @@
 from __future__ import annotations
 
-import pathlib
+import sys
+from pathlib import Path
 
 import numpy as np
 from numpy.typing import ArrayLike
 
-from ._common import num_nodes_per_cell
+from ._common import error, num_nodes_per_cell
 from ._exceptions import ReadError, WriteError
 from ._files import is_buffer
 from ._mesh import CellBlock, Mesh
 
-extension_to_filetype = {}
+extension_to_filetypes = {}
 reader_map = {}
 _writer_map = {}
 
 
-def register_format(name: str, extensions: list[str], reader, writer_map):
+def register_format(
+    format_name: str, extensions: list[str], reader, writer_map
+) -> None:
     for ext in extensions:
-        extension_to_filetype[ext] = name
+        if ext not in extension_to_filetypes:
+            extension_to_filetypes[ext] = []
+        extension_to_filetypes[ext].append(format_name)
 
     if reader is not None:
-        reader_map[name] = reader
+        reader_map[format_name] = reader
+
     _writer_map.update(writer_map)
 
 
-def _filetype_from_path(path: pathlib.Path):
+def deregister_format(format_name: str):
+    for value in extension_to_filetypes.values():
+        if format_name in value:
+            value.remove(format_name)
+
+    if format_name in reader_map:
+        reader_map.pop(format_name)
+
+    if format_name in _writer_map:
+        _writer_map.pop(format_name)
+
+
+def _filetypes_from_path(path: Path) -> list[str]:
     ext = ""
-    out = None
+    out = []
     for suffix in reversed(path.suffixes):
         ext = (suffix + ext).lower()
-        if ext in extension_to_filetype:
-            out = extension_to_filetype[ext]
+        try:
+            out += extension_to_filetypes[ext]
+        except KeyError:
+            pass
 
-    if out is None:
-        raise ReadError(f"Could not deduce file format from extension '{ext}'.")
+    if not out:
+        raise ReadError(f"Could not deduce file format from path '{path}'.")
     return out
 
 
@@ -46,31 +66,48 @@ def read(filename, file_format: str | None = None):
     :returns mesh{2,3}d: The mesh data.
     """
     if is_buffer(filename, "r"):
-        if file_format is None:
-            raise ReadError("File format must be given if buffer is used")
-        if file_format == "tetgen":
-            raise ReadError(
-                "tetgen format is spread across multiple files "
-                "and so cannot be read from a buffer"
-            )
-        msg = f"Unknown file format '{file_format}'"
-    else:
-        path = pathlib.Path(filename)
-        if not path.exists():
-            raise ReadError(f"File {filename} not found.")
+        return _read_buffer(filename, file_format)
 
-        if not file_format:
-            # deduce file format from extension
-            file_format = _filetype_from_path(path)
+    return _read_file(Path(filename), file_format)
 
-        msg = f"Unknown file format '{file_format}' of '{filename}'."
 
+def _read_buffer(filename, file_format: str | None):
+    if file_format is None:
+        raise ReadError("File format must be given if buffer is used")
+    if file_format == "tetgen":
+        raise ReadError(
+            "tetgen format is spread across multiple files "
+            "and so cannot be read from a buffer"
+        )
     if file_format not in reader_map:
-        raise ReadError(msg)
+        raise ReadError(f"Unknown file format '{file_format}'")
 
     return reader_map[file_format](filename)
 
 
+def _read_file(path: Path, file_format: str | None):
+    if not path.exists():
+        raise ReadError(f"File {path} not found.")
+
+    if file_format:
+        possible_file_formats = [file_format]
+    else:
+        # deduce possible file formats from extension
+        possible_file_formats = _filetypes_from_path(path)
+
+    for file_format in possible_file_formats:
+        if file_format not in reader_map:
+            raise ReadError(f"Unknown file format '{file_format}' of '{path}'.")
+
+        try:
+            return reader_map[file_format](str(path))
+        except ReadError:
+            pass
+
+    error(f"Couldn't read file {path} as either of {', '.join(possible_file_formats)}")
+    sys.exit(1)
+
+
 def write_points_cells(
     filename,
     points: ArrayLike,
@@ -113,10 +150,12 @@ def write(filename, mesh: Mesh, file_format: str | None = None, **kwargs):
                 "tetgen format is spread across multiple files, and so cannot be written to a buffer"
             )
     else:
-        path = pathlib.Path(filename)
+        path = Path(filename)
         if not file_format:
-            # deduce file format from extension
-            file_format = _filetype_from_path(path)
+            # deduce possible file formats from extension
+            file_formats = _filetypes_from_path(path)
+            # just take the first one
+            file_format = file_formats[0]
 
     try:
         writer = _writer_map[file_format]

src/meshio/ansys/_ansys.py

@@ -461,4 +461,4 @@ def write(filename, mesh, binary=True):
             first_index = last_index + 1
 
 
-register_format("ansys", [], read, {"ansys": write})
+register_format("ansys", [".msh"], read, {"ansys": write})

tests/test_public.py

@@ -3,4 +3,4 @@
 
 def test_public_attributes():
     # Just make sure this is here
-    meshio.extension_to_filetype
+    meshio.extension_to_filetypes