Composer broke riot - infinispinner on startup

[turt2live]

Uncaught TypeError: Cannot read property 'split' of undefined
    at Object.serialize (MessageComposerInput.js:198)
    at renderer.js:303
    at immutable.js:4418
    at immutable.js:3905
    at immutable.js:1377
    at ArrayMapNode.iterate.HashCollisionNode.iterate (immutable.js:1726)
    at Map.__iterate (immutable.js:1375)
    at Set.__iterate (immutable.js:3905)
    at Set.reduce (immutable.js:4413)
    at Markdown.serializeLeaves (renderer.js:293)
    at immutable.js:3016
    at List.__iterate (immutable.js:2206)
    at IndexedIterable.mappedSequence.__iterateUncached (immutable.js:3015)
    at seqIterate (immutable.js:604)
    at IndexedIterable.IndexedSeq.__iterate (immutable.js:320)
    at IndexedIterable.toArray (immutable.js:4258)
    at List [as constructor] (immutable.js:2065)
    at reify (immutable.js:3570)
    at List.map (immutable.js:4401)
    at Markdown.serializeNode (renderer.js:237)
    at renderer.js:241
    at immutable.js:3016
    at List.__iterate (immutable.js:2206)
    at IndexedIterable.mappedSequence.__iterateUncached (immutable.js:3015)
    at seqIterate (immutable.js:604)
    at IndexedIterable.IndexedSeq.__iterate (immutable.js:320)
    at IndexedIterable.toArray (immutable.js:4258)
    at List [as constructor] (immutable.js:2065)

No idea what happened, but below are the things I did before the thing died.

1. In #riot, notice a bug report about how the </> button doesn't work like it used to
2. Disable markdown
3. Press the </> button
4. Notice there's no code block, press the button again
5. Press it again, thinking maybe it'll work with text
6. Type "test" followed by a shift+enter for a newline and start typing "hello"
7. Select all, backspace
8. Click the code button again (to disable)
9. Switch to an encrypted private chat with someone
10. Turn on markdown
11. Try to switch back to #riot
12. Notice it's not working, see the split error in the console log
13. Refresh the page, thinking it'll just go away
14. Infinispinner, with the same split error in the console - followed by React falling apart
15. Open a new issue on riot-web

[turt2live]

Fixed by clearing out the editor state:

for (var k in localStorage) { 
    if (k.startsWith("editor_state")) localStorage.removeItem(k);
}

[ara4n]

i don't suppose you got a capture of the editor_state before you cleared it?

[turt2live]

... that would have been smart :(

I'll see if I can reproduce it.

[turt2live]

editor_state_!DgvjtOljKujDBrxyHk:matrix.org
{"editor_state":{"object":"value","document":{"object":"document","data":{},"nodes":[{"object":"block","type":"paragraph","isVoid":false,"data":{},"nodes":[{"object":"text","leaves":[{"object":"leaf","text":"","marks":[{"object":"mark","type":"code","data":{}}]}],"key":"177"}],"key":"176"}],"key":"175"},"selection":{"object":"range","anchorKey":"177","anchorOffset":0,"focusKey":"177","focusOffset":0,"isBackward":false,"isFocused":true,"marks":null,"isAtomic":false}},"rich_text":true}

editor_state_!PrivateChatRoom:redacted.com
{"editor_state":{"object":"value","document":{"object":"document","data":{},"nodes":[{"object":"block","type":"paragraph","isVoid":false,"data":{},"nodes":[{"object":"text","leaves":[{"object":"leaf","text":"","marks":[]}],"key":"312"}],"key":"311"}],"key":"310"},"selection":{"object":"range","anchorKey":"312","anchorOffset":0,"focusKey":"312","focusOffset":0,"isBackward":false,"isFocused":true,"marks":null,"isAtomic":false}},"rich_text":false}

Edit: smaller reproduction steps:

1. Go to a room
2. Disable markdown
3. Press the code block button
4. Type stuff
5. Delete that typed stuff
6. Disable code block
7. Go to another room
8. Enable markdown
9. Poof goes your editor state

[ara4n]

thanks!

[ara4n]

given this is taking out the whole app, it's more like a major or critical p1

[turt2live]

For reference, the part that is exploding is this:
https://github.com/matrix-org/matrix-react-sdk/blob/c5004ffbe3589756fcc575f35028397c1f4a7000/src/components/views/rooms/MessageComposerInput.js#L206-L209