Reject duplicate channel names

[pinch] / pinch.py

diff --git a/pinch.py b/pinch.py
index 46e5af30f9111043827bab3089040c1acaf1699f..787555f1c9a3c06831d52139b673a3e7e4e8087f 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -38,6 +38,7 @@ class ChannelTableEntry(types.SimpleNamespace):
 
 
 class Channel(types.SimpleNamespace):
+    alias_of: str
     channel_html: bytes
     channel_url: str
     forwarded_url: str
@@ -455,15 +456,25 @@ def git_revision_name(v: Verification, channel: Channel) -> str:
                       process.stdout.decode().strip())
 
 
+def read_config(filename: str) -> configparser.ConfigParser:
+    config = configparser.ConfigParser()
+    config.read_file(open(filename), filename)
+    return config
+
+
 def pin(args: argparse.Namespace) -> None:
     v = Verification()
-    config = configparser.ConfigParser()
-    config.read_file(open(args.channels_file), args.channels_file)
+    config = read_config(args.channels_file)
     for section in config.sections():
         if args.channels and section not in args.channels:
             continue
 
         channel = Channel(**dict(config[section].items()))
+
+        if hasattr(channel, 'alias_of'):
+            assert not hasattr(channel, 'git_repo')
+            continue
+
         if hasattr(channel, 'git_revision'):
             channel.old_git_revision = channel.git_revision
             del channel.git_revision
@@ -485,20 +496,37 @@ def pin(args: argparse.Namespace) -> None:
 def update(args: argparse.Namespace) -> None:
     v = Verification()
     config = configparser.ConfigParser()
-    config.read_file(open(args.channels_file), args.channels_file)
-    exprs = []
-    for section in config.sections():
-        if 'channel_url' in config[section]:
-            tarball = fetch_with_nix_prefetch_url(
-                v, config[section]['tarball_url'], Digest16(
-                    config[section]['tarball_sha256']))
-        else:
-            channel = Channel(**dict(config[section].items()))
-            ensure_git_rev_available(v, channel)
-            tarball = git_get_tarball(v, channel)
-        exprs.append(
-            'f: f { name = "%s"; channelName = "%s"; src = builtins.storePath "%s"; }' %
-            (config[section]['release_name'], section, tarball))
+    exprs = {}
+    configs = [read_config(filename) for filename in args.channels_file]
+    for config in configs:
+        for section in config.sections():
+
+            if 'alias_of' in config[section]:
+                assert 'git_repo' not in config[section]
+                continue
+
+            if 'channel_url' in config[section]:
+                tarball = fetch_with_nix_prefetch_url(
+                    v, config[section]['tarball_url'], Digest16(
+                        config[section]['tarball_sha256']))
+            else:
+                channel = Channel(**dict(config[section].items()))
+                ensure_git_rev_available(v, channel)
+                tarball = git_get_tarball(v, channel)
+
+            if section in exprs:
+                raise Exception('Duplicate channel "%s"' % section)
+            exprs[section] = (
+                'f: f { name = "%s"; channelName = "%%s"; src = builtins.storePath "%s"; }' %
+                (config[section]['release_name'], tarball))
+
+    for config in configs:
+        for section in config.sections():
+            if 'alias_of' in config[section]:
+                if section in exprs:
+                    raise Exception('Duplicate channel "%s"' % section)
+                exprs[section] = exprs[str(config[section]['alias_of'])]
+
     command = [
         'nix-env',
         '--profile',
@@ -508,7 +536,7 @@ def update(args: argparse.Namespace) -> None:
         '--file',
         '<nix/unpack-channel.nix>',
         '--install',
-        '--from-expression'] + exprs
+        '--from-expression'] + [exprs[name] % name for name in sorted(exprs.keys())]
     if args.dry_run:
         print(' '.join(map(shlex.quote, command)))
     else:
@@ -526,7 +554,7 @@ def main() -> None:
     parser_pin.set_defaults(func=pin)
     parser_update = subparsers.add_parser('update')
     parser_update.add_argument('--dry-run', action='store_true')
-    parser_update.add_argument('channels_file', type=str)
+    parser_update.add_argument('channels_file', type=str, nargs='+')
     parser_update.set_defaults(func=update)
     args = parser.parse_args()
     args.func(args)