support not uploading assets, through 'files: none'

README.md

@@ -51,6 +51,8 @@ Token to make authenticated API calls; can be passed in using `{{ secrets.GITHUB
 
 Either a single filename/pattern or a multi-line list can be provided. All the artifacts are uploaded regardless of the hierarchy.
 
+For creating/updating a release without uploading assets, set `files: none`.
+
 ## tag
 
 The default tag name for the tip/nightly pre-release is `tip`, but it can be optionally overriden through option `tag`.

tip.py

@@ -20,6 +20,10 @@ if 'INPUT_FILES' in environ:
 if len(argv) > 1:
     args = args + argv[1:]
 
+if len(args) == 1 and args[0] == 'none':
+    files = []
+    print("! Skipping 'files' because it's set to 'none")
+else:
     if len(args) == 0:
         stdout.flush()
         raise(Exception("Glob patterns need to be provided as positional arguments or through envvar 'INPUT_FILES'!"))
@@ -110,7 +114,7 @@ else:
     except Exception as e:
         raise(Exception(err_msg))
 
-print("· Upload artifacts")
+print("· Cleanup and/or upload artifacts")
 
 artifacts = files