Add patches for conda compatibility

For the conda-forge packages I package wgpu-native myself and install
them in the "system" libraries.

This should continue to allow you to use the "wheel" vendored headers
but then also look for the headers in the "system" locations.

I've been dragging on a simpler (less upstreamable) version of this
patch for about a year but I'm hoping I don't have to with this
addition.

wgpu/_coreutils.py

@@ -9,6 +9,7 @@
 import logging
 import importlib.resources
 from contextlib import ExitStack
+from pathlib import Path
 
 
 # Our resources are most probably always on the file system. But in
@@ -17,15 +18,52 @@
 atexit.register(_resource_files.close)
 
 
-def get_resource_filename(name):
-    """Get the filename to a wgpu resource."""
-    if sys.version_info < (3, 9):
-        context = importlib.resources.path("wgpu.resources", name)
-    else:
-        ref = importlib.resources.files("wgpu.resources") / name
-        context = importlib.resources.as_file(ref)
+def get_header_filename(name):
+    """Get the filename to a wgpu related header resource."""
+    ref = importlib.resources.files("wgpu.resources") / name
+    context = importlib.resources.as_file(ref)
     path = _resource_files.enter_context(context)
-    return str(path)
+    if path.exists():
+        return str(path)
+
+    # conda or system based installations may have the headers in other
+    # locations
+    path = Path(sys.exec_prefix) / "include" / name
+    if path.exists():
+        return str(path)
+
+    # Windows conda file layout is slightly different and includes a
+    # Library before the include directory
+    path = Path(sys.exec_prefix) / "Library" / "include" / name
+    if path.exists():
+        return str(path)
+
+    raise RuntimeError(f"Could not find the requested header file {name}.")
+
+
+def get_library_filename(name):
+    """Get the filename to a wgpu related library resource."""
+    ref = importlib.resources.files("wgpu.resources") / name
+    context = importlib.resources.as_file(ref)
+    path = _resource_files.enter_context(context)
+    if path.exists():
+        return str(path)
+
+    # conda or system based installations may have the headers in other
+    # locations
+    # Question for other linux distributions, how can we detect if we should
+    # be using `lib` or `lib64`????
+    path = Path(sys.exec_prefix) / "lib" / name
+    if path.exists():
+        return str(path)
+
+    # Windows conda file layout is slightly different and includes a
+    # Library before the include directory
+    path = Path(sys.exec_prefix) / "Library" / "bin" / name
+    if path.exists():
+        return str(path)
+
+    raise RuntimeError(f"Could not find the requested header file {name}.")
 
 
 class WGPULogger(logging.getLoggerClass()):

wgpu/backends/wgpu_native/_ffi.py

@@ -4,7 +4,11 @@
 import sys
 import logging
 
-from ..._coreutils import get_resource_filename, logger_set_level_callbacks
+from ..._coreutils import (
+    get_library_filename,
+    logger_set_level_callbacks,
+    get_header_filename,
+)
 
 from cffi import FFI, __version_info__ as cffi_version_info
 
@@ -19,8 +23,8 @@
 def get_wgpu_header():
     """Read header file and strip some stuff that cffi would stumble on."""
     return _get_wgpu_header(
-        get_resource_filename("webgpu.h"),
-        get_resource_filename("wgpu.h"),
+        get_header_filename("webgpu.h"),
+        get_header_filename("wgpu.h"),
     )
 
 
@@ -66,38 +70,44 @@ def get_wgpu_lib_path():
 
     # Load the debug binary if requested
     debug_mode = os.getenv("WGPU_DEBUG", "").strip() == "1"
-    build = "debug" if debug_mode else "release"
-
-    # Get lib filename for supported platforms
-    if sys.platform.startswith("win"):  # no-cover
-        lib_filename = f"wgpu_native-{build}.dll"
-    elif sys.platform.startswith("darwin"):  # no-cover
-        lib_filename = f"libwgpu_native-{build}.dylib"
-    elif sys.platform.startswith("linux"):  # no-cover
-        lib_filename = f"libwgpu_native-{build}.so"
-    else:  # no-cover
-        raise RuntimeError(
-            f"No WGPU library shipped for platform {sys.platform}. Set WGPU_LIB_PATH instead."
-        )
-
-    # Note that this can be a false positive, e.g. ARM linux.
-    embedded_path = get_resource_filename(lib_filename)
-    if not os.path.isfile(embedded_path):  # no-cover
-        env_hint = "You can set the WGPU_LIB_PATH env var to the location of the wgpu-native library."
-        download_hint = _maybe_get_hint_on_download_script().strip()
+    candidate_builds = ["-debug" if debug_mode else "-release"]
+    if not debug_mode:
+        candidate_builds.append("")
+
+    for build in candidate_builds:
+        # Get lib filename for supported platforms
+        if sys.platform.startswith("win"):  # no-cover
+            lib_filename = f"wgpu_native{build}.dll"
+        elif sys.platform.startswith("darwin"):  # no-cover
+            lib_filename = f"libwgpu_native{build}.dylib"
+        elif sys.platform.startswith("linux"):  # no-cover
+            lib_filename = f"libwgpu_native{build}.so"
+        else:  # no-cover
+            raise RuntimeError(
+                f"No WGPU library shipped for platform {sys.platform}. Set WGPU_LIB_PATH instead."
+            )
+
+        try:
+            embedded_path = get_library_filename(lib_filename)
+            return embedded_path
+        except RuntimeError:
+            pass
+    else:
+        main_hint = "Could not find WGPU library libwpgu_native."
         pip_hint = _maybe_get_pip_hint().strip()
-        hints = [pip_hint, download_hint, env_hint]
+        download_hint = _maybe_get_hint_on_download_script().strip()
+        env_hint = "You can set the WGPU_LIB_PATH env var to the location of the wgpu-native library."
+
+        hints = [main_hint, pip_hint, download_hint, env_hint]
         hints = "\n".join([hint for hint in hints if hint])
-        hints = "\n" + hints if hints else ""
-        raise RuntimeError(f"Could not find WGPU library in {embedded_path}.{hints}")
-    else:
-        return embedded_path
+        raise RuntimeError(hints)
 
 
 def _maybe_get_hint_on_download_script():
-    root_dir = os.path.join(get_resource_filename(""), "..", "..")
+    lib_module = sys.modules[__name__.split(".")[0]]
+    lib_dir = os.path.abspath(os.path.dirname(lib_module.__file__))
     filename = os.path.abspath(
-        os.path.join(root_dir, "tools", "download_wgpu_native.py")
+        os.path.join(lib_dir, "..", "tools", "download_wgpu_native.py")
     )
     uses_repo = os.path.isfile(filename)