How to write a NWProtocolFramer for Network.framework that splits streams into frames using a delimiter?

I tried to create a framer that splits a stream of ASCII bytes into frames separated by the pipe ascii character: "|". This framer is located in /Sources/SimpleFramer/SimpleFramer.swift

The problem is that from the moment I get a chunk that does not end with "|", the framer gets stuck on that chunk. So the other chunks that come after this incomplete chunk never fully arrive in the framer.parseInput(...) call. Because it always parses chunks of minimumIncompleteLength and hence never arrives to the point where the next "|" is.

Here is a simple reproduction of this problem:

1. Create a TCP server
2. Setup the server so that it sends chunks of messages when a client connects.
3. Connect to the server (created in 1.) using the framer from above.
4. Start receiving messages.

The code for this reproduction is located in /Tests/SimpleFramerTests/SimpleFramerTests.swift and can be run using the following command in the terminal

swift test

And produces the following console output:

🖲 server: waiting(POSIXErrorCode: Network is down)
🖲 server: ready
🖲 server: listening on 54907
👨‍💻 client: preparing
👨‍💻 client: ready
👨‍💻 client: receiving
🖲 server: new connection from ::1.52957
🖲 server (client ::1.52957): state setup
🖲 server (client ::1.52957): state ready
🖲 server: sending
🖲 server: sending "A|Be||Split in" 🖲
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "A|Be||Split in"
👨‍💻 client:		minLength set to 1
👨‍💻 client:		parsing buffer: "Be||Split in"
👨‍💻 client:		minLength set to 1
👨‍💻 client:		parsing buffer: "|Split in"
👨‍💻 client:		minLength set to 1
👨‍💻 client:		parsing buffer: "Split in"
👨‍💻 client:		minLength set to 9
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: ""
👨‍💻 client:		minLength set to 1
👨‍💻 client: received "A" Optional(Network.NWConnection.ContentContext) true No error
👨‍💻 client: received "Be" Optional(Network.NWConnection.ContentContext) true No error
👨‍💻 client: received "<no data>" Optional(Network.NWConnection.ContentContext) true No error
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "Split in"
👨‍💻 client:		minLength set to 9
🖲 server: sending " the middle|" 🖲
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "Split in "
👨‍💻 client:		minLength set to 10
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "Split in t"
👨‍💻 client:		minLength set to 11
🖲 server: sending "0|Done" 🖲
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "Split in th"
👨‍💻 client:		minLength set to 12
👨‍💻 client: handle input
👨‍💻 client:		parsing buffer: "Split in the"
👨‍💻 client:		minLength set to 13