Fix #4783: Sphinx crashed when drives of srcdir and outdir are different

CHANGES

@@ -20,6 +20,8 @@ Bugs fixed
 * #4790: autosummary: too wide two column tables in PDF builds
 * #4795: Latex customization via ``_templates/longtable.tex_t`` is broken
 * #4789: imgconverter: confused by convert.exe of Windows
+* #4783: On windows, Sphinx crashed when drives of srcdir and outdir are
+  different
 
 Testing
 --------

sphinx/application.py

@@ -40,7 +40,7 @@ from sphinx.util import pycompat  # noqa: F401
 from sphinx.util.console import bold  # type: ignore
 from sphinx.util.docutils import is_html5_writer_available, directive_helper
 from sphinx.util.i18n import find_catalog_source_files
-from sphinx.util.osutil import ENOENT, ensuredir
+from sphinx.util.osutil import ENOENT, ensuredir, relpath
 from sphinx.util.tags import Tags
 
 if False:
@@ -342,7 +342,7 @@ class Sphinx(object):
             if self.statuscode == 0 and self.builder.epilog:
                 logger.info('')
                 logger.info(self.builder.epilog % {
-                    'outdir': path.relpath(self.outdir),
+                    'outdir': relpath(self.outdir),
                     'project': self.config.project
                 })
         except Exception as err:

sphinx/builders/__init__.py

@@ -19,7 +19,7 @@ from sphinx.environment.adapters.asset import ImageAdapter
 from sphinx.util import i18n, logging, status_iterator
 from sphinx.util.console import bold  # type: ignore
 from sphinx.util.i18n import find_catalog
-from sphinx.util.osutil import SEP, ensuredir, relative_uri
+from sphinx.util.osutil import SEP, ensuredir, relative_uri, relpath
 from sphinx.util.parallel import ParallelTasks, SerialTasks, make_chunks, \
     parallel_available
 
@@ -237,7 +237,7 @@ class Builder(object):
 
         def cat2relpath(cat):
             # type: (CatalogInfo) -> unicode
-            return path.relpath(cat.mo_path, self.env.srcdir).replace(path.sep, SEP)
+            return relpath(cat.mo_path, self.env.srcdir).replace(path.sep, SEP)
 
         logger.info(bold('building [mo]: ') + message)
         for catalog in status_iterator(catalogs, 'writing output... ', "darkgreen",

sphinx/builders/gettext.py

@@ -26,7 +26,7 @@ from sphinx.util import split_index_msg, logging, status_iterator
 from sphinx.util.console import bold  # type: ignore
 from sphinx.util.i18n import find_catalog
 from sphinx.util.nodes import extract_messages, traverse_translatable_index
-from sphinx.util.osutil import safe_relpath, ensuredir, canon_path
+from sphinx.util.osutil import relpath, ensuredir, canon_path
 from sphinx.util.tags import Tags
 
 if False:
@@ -284,8 +284,7 @@ class MessageCatalogBuilder(I18nBuilder):
                 if self.config.gettext_location:
                     # generate "#: file1:line1\n#: file2:line2 ..."
                     output.write("#: %s\n" % "\n#: ".join(  # type: ignore
-                        "%s:%s" % (canon_path(
-                            safe_relpath(source, self.outdir)), line)
+                        "%s:%s" % (canon_path(relpath(source, self.outdir)), line)
                         for source, line, _ in positions))
                 if self.config.gettext_uuid:
                     # generate "# uuid1\n# uuid2\n ..."

sphinx/environment/__init__.py

@@ -38,7 +38,7 @@ from sphinx.util.docutils import sphinx_domains, WarningStream
 from sphinx.util.i18n import find_catalog_files
 from sphinx.util.matching import compile_matchers
 from sphinx.util.nodes import is_translatable
-from sphinx.util.osutil import SEP, ensuredir
+from sphinx.util.osutil import SEP, ensuredir, relpath
 from sphinx.util.parallel import ParallelTasks, parallel_available, make_chunks
 from sphinx.util.websupport import is_commentable
 
@@ -346,7 +346,7 @@ class BuildEnvironment(object):
         *filename* should be absolute or relative to the source directory.
         """
         if filename.startswith(self.srcdir):
-            filename = os.path.relpath(filename, self.srcdir)
+            filename = relpath(filename, self.srcdir)
         for suffix in self.config.source_suffix:
             if filename.endswith(suffix):
                 return filename[:-len(suffix)]

sphinx/ext/doctest.py

@@ -30,7 +30,7 @@ from sphinx.locale import _
 from sphinx.util import force_decode, logging
 from sphinx.util.console import bold  # type: ignore
 from sphinx.util.nodes import set_source_info
-from sphinx.util.osutil import fs_encoding
+from sphinx.util.osutil import fs_encoding, relpath
 
 if False:
     # For type annotation
@@ -372,7 +372,7 @@ Doctest summary
         """Try to get the file which actually contains the doctest, not the
         filename of the document it's included in."""
         try:
-            filename = path.relpath(node.source, self.env.srcdir)\
+            filename = relpath(node.source, self.env.srcdir)\
                 .rsplit(':docstring of ', maxsplit=1)[0]
         except Exception:
             filename = self.env.doc2path(docname, base=None)

sphinx/testing/util.py

@@ -23,6 +23,7 @@ from sphinx.builders.latex import LaTeXBuilder
 from sphinx.ext.autodoc import AutoDirective
 from sphinx.pycode import ModuleAnalyzer
 from sphinx.testing.path import path
+from sphinx.util.osutil import relpath
 
 if False:
     from typing import List  # NOQA
@@ -184,7 +185,7 @@ def find_files(root, suffix=None):
         dirpath = path(dirpath)
         for f in [f for f in files if not suffix or f.endswith(suffix)]:
             fpath = dirpath / f
-            yield os.path.relpath(fpath, root)
+            yield relpath(fpath, root)
 
 
 def strip_escseq(text):

sphinx/util/i18n.py

@@ -22,7 +22,7 @@ from babel.messages.pofile import read_po
 
 from sphinx.errors import SphinxError
 from sphinx.util import logging
-from sphinx.util.osutil import SEP, walk
+from sphinx.util.osutil import SEP, relpath, walk
 
 logger = logging.getLogger(__name__)
 
@@ -96,7 +96,7 @@ def find_catalog_files(docname, srcdir, locale_dirs, lang, compaction):
     domain = find_catalog(docname, compaction)
     files = [gettext.find(domain, path.join(srcdir, dir_), [lang])  # type: ignore
              for dir_ in locale_dirs]
-    files = [path.relpath(f, srcdir) for f in files if f]  # type: ignore
+    files = [relpath(f, srcdir) for f in files if f]  # type: ignore
     return files  # type: ignore
 
 
@@ -137,7 +137,7 @@ def find_catalog_source_files(locale_dirs, locale, domains=None, gettext_compact
             filenames = [f for f in filenames if f.endswith('.po')]
             for filename in filenames:
                 base = path.splitext(filename)[0]
-                domain = path.relpath(path.join(dirpath, base), base_dir)
+                domain = relpath(path.join(dirpath, base), base_dir)
                 if gettext_compact and path.sep in domain:
                     domain = path.split(domain)[0]
                 domain = domain.replace(path.sep, SEP)

sphinx/util/osutil.py

@@ -205,14 +205,21 @@ def ustrftime(format, *args):
             return r.encode().decode('unicode-escape')
 
 
-def safe_relpath(path, start=None):
+def relpath(path, start=os.curdir):
     # type: (unicode, unicode) -> unicode
+    """Return a relative filepath to *path* either from the current directory or
+    from an optional *start* directory.
+
+    This is an alternative of ``os.path.relpath()``.  This returns original path
+    if *path* and *start* are on different drives (for Windows platform).
+    """
     try:
         return os.path.relpath(path, start)
     except ValueError:
         return path
 
 
+safe_relpath = relpath  # for compatibility
 fs_encoding = sys.getfilesystemencoding() or sys.getdefaultencoding()  # type: unicode