diff --git a/lib/_emerge/BinpkgVerifier.py b/lib/_emerge/BinpkgVerifier.py
index 7a6d15e..f98f511 100644
--- a/lib/_emerge/BinpkgVerifier.py
+++ b/lib/_emerge/BinpkgVerifier.py
@@ -1,4 +1,4 @@
-# Copyright 1999-2013 Gentoo Foundation
+# Copyright 1999-2019 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 import errno
@@ -108,7 +108,7 @@
 	def _digest_exception(self, name, value, expected):
 
 		head, tail = os.path.split(self._pkg_path)
-		temp_filename = _checksum_failure_temp_file(head, tail)
+		temp_filename = _checksum_failure_temp_file(self.pkg.root_config.settings, head, tail)
 
 		self.scheduler.output((
 			"\n!!! Digest verification failed:\n"
diff --git a/lib/portage/package/ebuild/fetch.py b/lib/portage/package/ebuild/fetch.py
index bfd9760..227bf45 100644
--- a/lib/portage/package/ebuild/fetch.py
+++ b/lib/portage/package/ebuild/fetch.py
@@ -30,7 +30,7 @@
 )
 
 from portage import os, selinux, shutil, _encodings, \
-	_shell_quote, _unicode_encode
+	_movefile, _shell_quote, _unicode_encode
 from portage.checksum import (get_valid_checksum_keys, perform_md5, verify_all,
 	_filter_unaccelarated_hashes, _hash_filter, _apply_hash_filter)
 from portage.const import BASH_BINARY, CUSTOM_MIRRORS_FILE, \
@@ -46,6 +46,8 @@
 	varexpand, writemsg, writemsg_level, writemsg_stdout
 from portage.process import spawn
 
+_download_suffix = '.__download__'
+
 _userpriv_spawn_kwargs = (
 	("uid",    portage_uid),
 	("gid",    portage_gid),
@@ -139,7 +141,7 @@
 	_userpriv_test_write_file_cache[file_path] = rval
 	return rval
 
-def _checksum_failure_temp_file(distdir, basename):
+def _checksum_failure_temp_file(settings, distdir, basename):
 	"""
 	First try to find a duplicate temp file with the same checksum and return
 	that filename if available. Otherwise, use mkstemp to create a new unique
@@ -149,9 +151,13 @@
 	"""
 
 	filename = os.path.join(distdir, basename)
+	if basename.endswith(_download_suffix):
+		normal_basename = basename[:-len(_download_suffix)]
+	else:
+		normal_basename = basename
 	size = os.stat(filename).st_size
 	checksum = None
-	tempfile_re = re.compile(re.escape(basename) + r'\._checksum_failure_\..*')
+	tempfile_re = re.compile(re.escape(normal_basename) + r'\._checksum_failure_\..*')
 	for temp_filename in os.listdir(distdir):
 		if not tempfile_re.match(temp_filename):
 			continue
@@ -173,9 +179,9 @@
 			return temp_filename
 
 	fd, temp_filename = \
-		tempfile.mkstemp("", basename + "._checksum_failure_.", distdir)
+		tempfile.mkstemp("", normal_basename + "._checksum_failure_.", distdir)
 	os.close(fd)
-	os.rename(filename, temp_filename)
+	_movefile(filename, temp_filename, mysettings=settings)
 	return temp_filename
 
 def _check_digests(filename, digests, show_errors=1):
@@ -602,6 +608,7 @@
 				pruned_digests["size"] = size
 
 		myfile_path = os.path.join(mysettings["DISTDIR"], myfile)
+		download_path = myfile_path + _download_suffix
 		has_space = True
 		has_space_superuser = True
 		file_lock = None
@@ -679,12 +686,15 @@
 							del e
 					continue
 
-				if distdir_writable and mystat is None:
-					# Remove broken symlinks if necessary.
+				# Remove broken symlinks or symlinks to files which
+				# _check_distfile did not match above.
+				if distdir_writable and mystat is None or os.path.islink(myfile_path):
 					try:
 						os.unlink(myfile_path)
-					except OSError:
-						pass
+					except OSError as e:
+						if e.errno not in (errno.ENOENT, errno.ESTALE):
+							raise
+					mystat = None
 
 				if mystat is not None:
 					if stat.S_ISDIR(mystat.st_mode):
@@ -695,10 +705,30 @@
 							level=logging.ERROR, noiselevel=-1)
 						return 0
 
+					if distdir_writable:
+						# Since _check_distfile did not match above, the file
+						# is either corrupt or its identity has changed since
+						# the last time it was fetched, so rename it.
+						temp_filename = _checksum_failure_temp_file(
+							mysettings, mysettings["DISTDIR"], myfile)
+						writemsg_stdout(_("Refetching... "
+							"File renamed to '%s'\n\n") % \
+							temp_filename, noiselevel=-1)
+
+				# Stat the temporary download file for comparison with
+				# fetch_resume_size.
+				try:
+					mystat = os.stat(download_path)
+				except OSError as e:
+					if e.errno not in (errno.ENOENT, errno.ESTALE):
+						raise
+					mystat = None
+
+				if mystat is not None:
 					if mystat.st_size == 0:
 						if distdir_writable:
 							try:
-								os.unlink(myfile_path)
+								os.unlink(download_path)
 							except OSError:
 								pass
 					elif distdir_writable and size is not None:
@@ -717,14 +747,16 @@
 								"ME_MIN_SIZE)\n") % mystat.st_size)
 							temp_filename = \
 								_checksum_failure_temp_file(
-								mysettings["DISTDIR"], myfile)
+									mysettings, mysettings["DISTDIR"],
+									os.path.basename(download_path))
 							writemsg_stdout(_("Refetching... "
 								"File renamed to '%s'\n\n") % \
 								temp_filename, noiselevel=-1)
 						elif mystat.st_size >= size:
 							temp_filename = \
 								_checksum_failure_temp_file(
-								mysettings["DISTDIR"], myfile)
+									mysettings, mysettings["DISTDIR"],
+									os.path.basename(download_path))
 							writemsg_stdout(_("Refetching... "
 								"File renamed to '%s'\n\n") % \
 								temp_filename, noiselevel=-1)
@@ -766,7 +798,7 @@
 					for mydir in fsmirrors:
 						mirror_file = os.path.join(mydir, myfile)
 						try:
-							shutil.copyfile(mirror_file, myfile_path)
+							shutil.copyfile(mirror_file, download_path)
 							writemsg(_("Local mirror has file: %s\n") % myfile)
 							break
 						except (IOError, OSError) as e:
@@ -775,7 +807,7 @@
 							del e
 
 				try:
-					mystat = os.stat(myfile_path)
+					mystat = os.stat(download_path)
 				except OSError as e:
 					if e.errno not in (errno.ENOENT, errno.ESTALE):
 						raise
@@ -784,13 +816,13 @@
 					# Skip permission adjustment for symlinks, since we don't
 					# want to modify anything outside of the primary DISTDIR,
 					# and symlinks typically point to PORTAGE_RO_DISTDIRS.
-					if not os.path.islink(myfile_path):
+					if not os.path.islink(download_path):
 						try:
-							apply_secpass_permissions(myfile_path,
+							apply_secpass_permissions(download_path,
 								gid=portage_gid, mode=0o664, mask=0o2,
 								stat_cached=mystat)
 						except PortageException as e:
-							if not os.access(myfile_path, os.R_OK):
+							if not os.access(download_path, os.R_OK):
 								writemsg(_("!!! Failed to adjust permissions:"
 									" %s\n") % (e,), noiselevel=-1)
 
@@ -799,7 +831,7 @@
 					if mystat.st_size == 0:
 						if distdir_writable:
 							try:
-								os.unlink(myfile_path)
+								os.unlink(download_path)
 							except EnvironmentError:
 								pass
 					elif myfile not in mydigests:
@@ -824,7 +856,7 @@
 							digests = _filter_unaccelarated_hashes(mydigests[myfile])
 							if hash_filter is not None:
 								digests = _apply_hash_filter(digests, hash_filter)
-							verified_ok, reason = verify_all(myfile_path, digests)
+							verified_ok, reason = verify_all(download_path, digests)
 							if not verified_ok:
 								writemsg(_("!!! Previously fetched"
 									" file: '%s'\n") % myfile, noiselevel=-1)
@@ -838,11 +870,13 @@
 								if distdir_writable:
 									temp_filename = \
 										_checksum_failure_temp_file(
-										mysettings["DISTDIR"], myfile)
+											mysettings, mysettings["DISTDIR"],
+											os.path.basename(download_path))
 									writemsg_stdout(_("Refetching... "
 										"File renamed to '%s'\n\n") % \
 										temp_filename, noiselevel=-1)
 							else:
+								_movefile(download_path, myfile_path, mysettings=mysettings)
 								eout = EOutput()
 								eout.quiet = \
 									mysettings.get("PORTAGE_QUIET", None) == "1"
@@ -928,7 +962,7 @@
 				if not can_fetch:
 					if fetched != 2:
 						try:
-							mysize = os.stat(myfile_path).st_size
+							mysize = os.stat(download_path).st_size
 						except OSError as e:
 							if e.errno not in (errno.ENOENT, errno.ESTALE):
 								raise
@@ -952,7 +986,7 @@
 					#we either need to resume or start the download
 					if fetched == 1:
 						try:
-							mystat = os.stat(myfile_path)
+							mystat = os.stat(download_path)
 						except OSError as e:
 							if e.errno not in (errno.ENOENT, errno.ESTALE):
 								raise
@@ -964,7 +998,7 @@
 									"%d (smaller than " "PORTAGE_FETCH_RESU"
 									"ME_MIN_SIZE)\n") % mystat.st_size)
 								try:
-									os.unlink(myfile_path)
+									os.unlink(download_path)
 								except OSError as e:
 									if e.errno not in \
 										(errno.ENOENT, errno.ESTALE):
@@ -984,7 +1018,7 @@
 						_hide_url_passwd(loc))
 					variables = {
 						"URI":     loc,
-						"FILE":    myfile
+						"FILE":    os.path.basename(download_path)
 					}
 
 					for k in ("DISTDIR", "PORTAGE_SSH_OPTS"):
@@ -1001,12 +1035,12 @@
 
 					finally:
 						try:
-							apply_secpass_permissions(myfile_path,
+							apply_secpass_permissions(download_path,
 								gid=portage_gid, mode=0o664, mask=0o2)
 						except FileNotFound:
 							pass
 						except PortageException as e:
-							if not os.access(myfile_path, os.R_OK):
+							if not os.access(download_path, os.R_OK):
 								writemsg(_("!!! Failed to adjust permissions:"
 									" %s\n") % str(e), noiselevel=-1)
 							del e
@@ -1015,8 +1049,8 @@
 					# trust the return value from the fetcher.  Remove the
 					# empty file and try to download again.
 					try:
-						if os.stat(myfile_path).st_size == 0:
-							os.unlink(myfile_path)
+						if os.stat(download_path).st_size == 0:
+							os.unlink(download_path)
 							fetched = 0
 							continue
 					except EnvironmentError:
@@ -1024,7 +1058,7 @@
 
 					if mydigests is not None and myfile in mydigests:
 						try:
-							mystat = os.stat(myfile_path)
+							mystat = os.stat(download_path)
 						except OSError as e:
 							if e.errno not in (errno.ENOENT, errno.ESTALE):
 								raise
@@ -1065,13 +1099,13 @@
 								if (mystat[stat.ST_SIZE]<100000) and (len(myfile)>4) and not ((myfile[-5:]==".html") or (myfile[-4:]==".htm")):
 									html404=re.compile("<title>.*(not found|404).*</title>",re.I|re.M)
 									with io.open(
-										_unicode_encode(myfile_path,
+										_unicode_encode(download_path,
 										encoding=_encodings['fs'], errors='strict'),
 										mode='r', encoding=_encodings['content'], errors='replace'
 										) as f:
 										if html404.search(f.read()):
 											try:
-												os.unlink(mysettings["DISTDIR"]+"/"+myfile)
+												os.unlink(download_path)
 												writemsg(_(">>> Deleting invalid distfile. (Improper 404 redirect from server.)\n"))
 												fetched = 0
 												continue
@@ -1087,7 +1121,7 @@
 								digests = _filter_unaccelarated_hashes(mydigests[myfile])
 								if hash_filter is not None:
 									digests = _apply_hash_filter(digests, hash_filter)
-								verified_ok, reason = verify_all(myfile_path, digests)
+								verified_ok, reason = verify_all(download_path, digests)
 								if not verified_ok:
 									writemsg(_("!!! Fetched file: %s VERIFY FAILED!\n") % myfile,
 										noiselevel=-1)
@@ -1099,7 +1133,8 @@
 										return 0
 									temp_filename = \
 										_checksum_failure_temp_file(
-										mysettings["DISTDIR"], myfile)
+											mysettings, mysettings["DISTDIR"],
+											os.path.basename(download_path))
 									writemsg_stdout(_("Refetching... "
 										"File renamed to '%s'\n\n") % \
 										temp_filename, noiselevel=-1)
@@ -1119,6 +1154,7 @@
 										checksum_failure_max_tries:
 										break
 								else:
+									_movefile(download_path, myfile_path, mysettings=mysettings)
 									eout = EOutput()
 									eout.quiet = mysettings.get("PORTAGE_QUIET", None) == "1"
 									if digests:
@@ -1127,8 +1163,9 @@
 										eout.eend(0)
 									fetched=2
 									break
-					else:
+					else: # no digests available
 						if not myret:
+							_movefile(download_path, myfile_path, mysettings=mysettings)
 							fetched=2
 							break
 						elif mydigests!=None:
diff --git a/lib/portage/tests/ebuild/test_fetch.py b/lib/portage/tests/ebuild/test_fetch.py
new file mode 100644
index 0000000..83321fe
--- /dev/null
+++ b/lib/portage/tests/ebuild/test_fetch.py
@@ -0,0 +1,230 @@
+# Copyright 2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+from __future__ import unicode_literals
+
+import functools
+import tempfile
+
+import portage
+from portage import shutil, os
+from portage.tests import TestCase
+from portage.tests.resolver.ResolverPlayground import ResolverPlayground
+from portage.tests.util.test_socks5 import AsyncHTTPServer
+from portage.util.futures.executor.fork import ForkExecutor
+from portage.util._async.SchedulerInterface import SchedulerInterface
+from portage.util._eventloop.global_event_loop import global_event_loop
+from portage.package.ebuild.config import config
+from portage.package.ebuild.digestgen import digestgen
+from portage.package.ebuild.fetch import _download_suffix
+from _emerge.EbuildFetcher import EbuildFetcher
+from _emerge.Package import Package
+
+
+class EbuildFetchTestCase(TestCase):
+
+	def testEbuildFetch(self):
+
+		distfiles = {
+			'bar': b'bar\n',
+			'foo': b'foo\n',
+		}
+
+		ebuilds = {
+			'dev-libs/A-1': {
+				'EAPI': '7',
+				'RESTRICT': 'primaryuri',
+				'SRC_URI': '''{scheme}://{host}:{port}/distfiles/bar.txt -> bar
+					{scheme}://{host}:{port}/distfiles/foo.txt -> foo''',
+			},
+		}
+
+		loop = SchedulerInterface(global_event_loop())
+		scheme = 'http'
+		host = '127.0.0.1'
+		content = {}
+		for k, v in distfiles.items():
+			content['/distfiles/{}.txt'.format(k)] = v
+
+		with AsyncHTTPServer(host, content, loop) as server:
+			ebuilds_subst = {}
+			for cpv, metadata in ebuilds.items():
+				metadata = metadata.copy()
+				metadata['SRC_URI'] = metadata['SRC_URI'].format(
+					scheme=scheme, host=host, port=server.server_port)
+				ebuilds_subst[cpv] = metadata
+
+			playground = ResolverPlayground(ebuilds=ebuilds_subst, distfiles=distfiles)
+			ro_distdir = tempfile.mkdtemp()
+			try:
+				fetchcommand = portage.util.shlex_split(playground.settings['FETCHCOMMAND'])
+				fetch_bin = portage.process.find_binary(fetchcommand[0])
+				if fetch_bin is None:
+					self.skipTest('FETCHCOMMAND not found: {}'.format(playground.settings['FETCHCOMMAND']))
+				resumecommand = portage.util.shlex_split(playground.settings['RESUMECOMMAND'])
+				resume_bin = portage.process.find_binary(resumecommand[0])
+				if resume_bin is None:
+					self.skipTest('RESUMECOMMAND not found: {}'.format(playground.settings['RESUMECOMMAND']))
+				root_config = playground.trees[playground.eroot]['root_config']
+				portdb = root_config.trees["porttree"].dbapi
+				settings = config(clone=playground.settings)
+
+				# Tests only work with one ebuild at a time, so the config
+				# pool only needs a single config instance.
+				class config_pool:
+					@staticmethod
+					def allocate():
+						return settings
+					@staticmethod
+					def deallocate(settings):
+						pass
+
+				def async_fetch(pkg, ebuild_path):
+					fetcher = EbuildFetcher(config_pool=config_pool, ebuild_path=ebuild_path,
+						fetchonly=False, fetchall=True, pkg=pkg, scheduler=loop)
+					fetcher.start()
+					return fetcher.async_wait()
+
+				for cpv in ebuilds:
+					metadata = dict(zip(Package.metadata_keys,
+						portdb.aux_get(cpv, Package.metadata_keys)))
+
+					pkg = Package(built=False, cpv=cpv, installed=False,
+						metadata=metadata, root_config=root_config,
+						type_name='ebuild')
+
+					settings.setcpv(pkg)
+					ebuild_path = portdb.findname(pkg.cpv)
+					portage.doebuild_environment(ebuild_path, 'fetch', settings=settings, db=portdb)
+
+					# Test good files in DISTDIR
+					for k in settings['AA'].split():
+						os.stat(os.path.join(settings['DISTDIR'], k))
+					self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+					for k in settings['AA'].split():
+						with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+							self.assertEqual(f.read(), distfiles[k])
+
+					# Test digestgen with fetch
+					os.unlink(os.path.join(os.path.dirname(ebuild_path), 'Manifest'))
+					for k in settings['AA'].split():
+						os.unlink(os.path.join(settings['DISTDIR'], k))
+					with ForkExecutor(loop=loop) as executor:
+						self.assertTrue(bool(loop.run_until_complete(
+							loop.run_in_executor(executor, functools.partial(
+								digestgen, mysettings=settings, myportdb=portdb)))))
+					for k in settings['AA'].split():
+						with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+							self.assertEqual(f.read(), distfiles[k])
+
+					# Test missing files in DISTDIR
+					for k in settings['AA'].split():
+						os.unlink(os.path.join(settings['DISTDIR'], k))
+					self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+					for k in settings['AA'].split():
+						with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+							self.assertEqual(f.read(), distfiles[k])
+
+					# Test empty files in DISTDIR
+					for k in settings['AA'].split():
+						file_path = os.path.join(settings['DISTDIR'], k)
+						with open(file_path, 'wb') as f:
+							pass
+						self.assertEqual(os.stat(file_path).st_size, 0)
+					self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+					for k in settings['AA'].split():
+						with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+							self.assertEqual(f.read(), distfiles[k])
+
+					# Test non-empty files containing null bytes in DISTDIR
+					for k in settings['AA'].split():
+						file_path = os.path.join(settings['DISTDIR'], k)
+						with open(file_path, 'wb') as f:
+							f.write(len(distfiles[k]) * b'\0')
+						self.assertEqual(os.stat(file_path).st_size, len(distfiles[k]))
+					self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+					for k in settings['AA'].split():
+						with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+							self.assertEqual(f.read(), distfiles[k])
+
+					# Test PORTAGE_RO_DISTDIRS
+					settings['PORTAGE_RO_DISTDIRS'] = '"{}"'.format(ro_distdir)
+					orig_fetchcommand = settings['FETCHCOMMAND']
+					orig_resumecommand = settings['RESUMECOMMAND']
+					try:
+						settings['FETCHCOMMAND'] = settings['RESUMECOMMAND'] = ''
+						for k in settings['AA'].split():
+							file_path = os.path.join(settings['DISTDIR'], k)
+							os.rename(file_path, os.path.join(ro_distdir, k))
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							file_path = os.path.join(settings['DISTDIR'], k)
+							self.assertTrue(os.path.islink(file_path))
+							with open(file_path, 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+							os.unlink(file_path)
+					finally:
+						settings.pop('PORTAGE_RO_DISTDIRS')
+						settings['FETCHCOMMAND'] = orig_fetchcommand
+						settings['RESUMECOMMAND'] = orig_resumecommand
+
+					# Test local filesystem in GENTOO_MIRRORS
+					orig_mirrors = settings['GENTOO_MIRRORS']
+					orig_fetchcommand = settings['FETCHCOMMAND']
+					try:
+						settings['GENTOO_MIRRORS'] = ro_distdir
+						settings['FETCHCOMMAND'] = settings['RESUMECOMMAND'] = ''
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+					finally:
+						settings['GENTOO_MIRRORS'] = orig_mirrors
+						settings['FETCHCOMMAND'] = orig_fetchcommand
+						settings['RESUMECOMMAND'] = orig_resumecommand
+
+					# Test readonly DISTDIR
+					orig_distdir_mode = os.stat(settings['DISTDIR']).st_mode
+					try:
+						os.chmod(settings['DISTDIR'], 0o555)
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+					finally:
+						os.chmod(settings['DISTDIR'], orig_distdir_mode)
+
+					# Test parallel-fetch mode
+					settings['PORTAGE_PARALLEL_FETCHONLY'] = '1'
+					try:
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+						for k in settings['AA'].split():
+							os.unlink(os.path.join(settings['DISTDIR'], k))
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+					finally:
+						settings.pop('PORTAGE_PARALLEL_FETCHONLY')
+
+					# Test RESUMECOMMAND
+					orig_resume_min_size = settings['PORTAGE_FETCH_RESUME_MIN_SIZE']
+					try:
+						settings['PORTAGE_FETCH_RESUME_MIN_SIZE'] = '2'
+						for k in settings['AA'].split():
+							file_path = os.path.join(settings['DISTDIR'], k)
+							os.unlink(file_path)
+							with open(file_path + _download_suffix, 'wb') as f:
+								f.write(distfiles[k][:2])
+						self.assertEqual(loop.run_until_complete(async_fetch(pkg, ebuild_path)), 0)
+						for k in settings['AA'].split():
+							with open(os.path.join(settings['DISTDIR'], k), 'rb') as f:
+								self.assertEqual(f.read(), distfiles[k])
+					finally:
+						settings['PORTAGE_FETCH_RESUME_MIN_SIZE'] = orig_resume_min_size
+			finally:
+				shutil.rmtree(ro_distdir)
+				playground.cleanup()