Refactor fetch() for selective restrictions

Refactor the fetch() function so that fetch/mirror restrictions only
affect the code per-URI rather than globally.  This will make it easier
to apply restrictions selectively in EAPI 8.

Signed-off-by: Michał Górny <mgorny@gentoo.org>
Signed-off-by: Zac Medico <zmedico@gentoo.org>

1 files changed, 26 insertions, 28 deletions

diff --git a/lib/portage/package/ebuild/fetch.py b/lib/portage/package/ebuild/fetch.py
index 73abec595..2f3111b65 100644
--- a/lib/portage/package/ebuild/fetch.py
+++ b/lib/portage/package/ebuild/fetch.py
@@ -813,8 +813,6 @@ def fetch(myuris, mysettings, listonly=0, fetchonly=0,
 	custommirrors = grabdict(os.path.join(mysettings["PORTAGE_CONFIGROOT"],
 		CUSTOM_MIRRORS_FILE), recursive=1)
 
-	mymirrors=[]
-
 	if listonly or ("distlocks" not in features):
 		use_locks = 0
 
@@ -832,16 +830,22 @@ def fetch(myuris, mysettings, listonly=0, fetchonly=0,
 				"FEATURES in /etc/portage/make.conf\n"), noiselevel=-1)
 #			use_locks = 0
 
-	# local mirrors are always added
-	if try_mirrors and "local" in custommirrors:
-		mymirrors += custommirrors["local"]
-
-	if restrict_mirror:
-		# We don't add any mirrors.
-		pass
-	else:
-		if try_mirrors:
-			mymirrors += [x.rstrip("/") for x in mysettings["GENTOO_MIRRORS"].split() if x]
+	local_mirrors = []
+	public_mirrors = []
+	fsmirrors = []
+	if try_mirrors:
+		for x in custommirrors.get("local", []):
+			if x.startswith("/"):
+				fsmirrors.append(x)
+			else:
+				local_mirrors.append(x)
+		for x in mysettings["GENTOO_MIRRORS"].split():
+			if not x:
+				continue
+			if x.startswith('/'):
+				fsmirrors.append(x.rstrip("/"))
+			else:
+				public_mirrors.append(x.rstrip("/"))
 
 	hash_filter = _hash_filter(mysettings.get("PORTAGE_CHECKSUM_FILTER", ""))
 	if hash_filter.transparent:
@@ -864,23 +868,8 @@ def fetch(myuris, mysettings, listonly=0, fetchonly=0,
 		shlex_split(mysettings.get("PORTAGE_RO_DISTDIRS", "")) \
 		if os.path.isdir(x)]
 
-	fsmirrors = []
-	for x in range(len(mymirrors)-1,-1,-1):
-		if mymirrors[x] and mymirrors[x][0]=='/':
-			fsmirrors += [mymirrors[x]]
-			del mymirrors[x]
-
 	restrict_fetch = "fetch" in restrict
 	force_mirror = "force-mirror" in features and not restrict_mirror
-	custom_local_mirrors = custommirrors.get("local", [])
-	if restrict_fetch:
-		# With fetch restriction, a normal uri may only be fetched from
-		# custom local mirrors (if available).  A mirror:// uri may also
-		# be fetched from specific mirrors (effectively overriding fetch
-		# restriction, but only for specific mirrors).
-		locations = custom_local_mirrors
-	else:
-		locations = mymirrors
 
 	file_uri_tuples = []
 	# Check for 'items' attribute since OrderedDict is not a dict.
@@ -916,7 +905,16 @@ def fetch(myuris, mysettings, listonly=0, fetchonly=0,
 						".mirror-cache.json")
 			else:
 				mirror_cache = None
-			for l in locations:
+
+			# With fetch restriction, a normal uri may only be fetched from
+			# custom local mirrors (if available).  A mirror:// uri may also
+			# be fetched from specific mirrors (effectively overriding fetch
+			# restriction, but only for specific mirrors).
+			location_lists = [local_mirrors]
+			if not restrict_fetch and not restrict_mirror:
+				location_lists.append(public_mirrors)
+
+			for l in itertools.chain(*location_lists):
 				filedict[myfile].append(functools.partial(
 					get_mirror_url, l, myfile, mysettings, mirror_cache))
 		if myuri is None: