bugfix [#23194] export UVs miss the extension file

also made all other exporters do this.

Made some internal changes.
- moved path functions from bpy.utils to bpy.path (similar to os.path)
- added functions...
  bpy.path.ensure_ext(path, ".ext", case_sensitive=False) # simple function to ensure the extension is set.
  bpy.path.resolve_ncase(path) # useful for importing scenes made on windows where the path case doesnt match the files.

release/scripts/modules/bpy/path.py

@@ -0,0 +1,173 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+# <pep8 compliant>
+
+"""
+This module has a similar scope to os.path, containing utility
+functions for dealing with paths in Blender.
+"""
+
+import bpy as _bpy
+
+
+def expand(path):
+    """
+    Returns the absolute path relative to the current blend file using the "//" prefix.
+    """
+    if path.startswith("//"):
+        return _os.path.join(_os.path.dirname(_bpy.data.filepath), path[2:])
+
+    return path
+
+
+def relpath(path, start=None):
+    """
+    Returns the path relative to the current blend file using the "//" prefix.
+
+    :arg start: Relative to this path, when not set the current filename is used.
+    :type start: string
+    """
+    if not path.startswith("//"):
+        if start is None:
+            start = _os.path.dirname(_bpy.data.filepath)
+        return "//" + _os.path.relpath(path, start)
+
+    return path
+
+
+def clean_name(name, replace="_"):
+    """
+    Returns a name with characters replaced that may cause problems under various circumstances, such as writing to a file.
+    All characters besides A-Z/a-z, 0-9 are replaced with "_"
+    or the replace argument if defined.
+    """
+
+    unclean_chars = \
+                 "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\
+                  \x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\
+                  \x1e\x1f\x20\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\
+                  \x2e\x2f\x3a\x3b\x3c\x3d\x3e\x3f\x40\x5b\x5c\x5d\x5e\x60\x7b\
+                  \x7c\x7d\x7e\x7f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\
+                  \x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\
+                  \x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\
+                  \xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\
+                  \xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\
+                  \xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\
+                  \xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\
+                  \xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\
+                  \xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe"
+
+    for ch in unclean_chars:
+        name = name.replace(ch, replace)
+    return name
+
+
+def display_name(name):
+    """
+    Creates a display string from name to be used menus and the user interface.
+    Capitalize the first letter in all lowercase names, mixed case names are kept as is.
+    Intended for use with filenames and module names.
+    """
+    name_base = _os.path.splitext(name)[0]
+
+    # string replacements
+    name_base = name_base.replace("_colon_", ":")
+
+    name_base = name_base.replace("_", " ")
+
+    if name_base.islower():
+        return name_base.capitalize()
+    else:
+        return name_base
+
+
+def resolve_ncase(path):
+	"""
+	Resolve a case insensitive path on a case sensitive system,
+	returning a string with the path if found else return the original path.
+	"""
+
+	import os
+
+	def _ncase_path_found(path):
+		if path=='' or os.path.exists(path):
+			return path, True
+
+		filename = os.path.basename(path) # filename may be a directory or a file
+		dirpath = os.path.dirname(path)
+
+		suffix = ""
+		if not filename: # dir ends with a slash?
+			if len(dirpath) < len(path):
+				suffix = path[:len(path)-len(dirpath)]
+
+			filename = os.path.basename(dirpath)
+			dirpath = os.path.dirname(dirpath)
+
+		if not os.path.exists(dirpath):
+			dirpath, found = _ncase_path_found(dirpath)
+
+			if not found:
+				return path, False
+
+		# at this point, the directory exists but not the file
+
+		# we are expecting 'dirpath' to be a directory, but it could be a file
+		if os.path.isdir(dirpath):
+			files = os.listdir(dirpath)
+		else:
+			return path, False
+
+		filename_low = filename.lower()
+		f_iter_nocase = None
+
+		for f_iter in files:
+			if f_iter.lower() == filename_low:
+				f_iter_nocase = f_iter
+				break
+
+		if f_iter_nocase:
+			return os.path.join(dirpath, f_iter_nocase) + suffix, True
+		else:
+			# cant find the right one, just return the path as is.
+			return path, False
+
+	ncase_path, found = _ncase_path_found(path)
+	return ncase_path if found else path
+
+
+def ensure_ext(filepath, ext, case_sensitive=False):
+    """
+    Return the path with the extension added its its not alredy set.
+
+    :arg ext: The extension to check for.
+    :type ext: string
+    :arg case_sensitive: Check for matching case when comparing extensions.
+    :type case_sensitive: bool
+    """
+    import os
+    fn_base, fn_ext = os.path.splitext(filepath)
+    if fn_base and fn_ext:
+        if (case_sensitive and ext == fn_ext) or (ext.lower() == fn_ext.lower()):
+            return filepath
+        else:
+            return fn_base + ext
+
+    else:
+        return filepath + ext