App: [WAITING ON CHECKLIST] [HOLD for payment 2023-10-23] [$500] Room - Division sign (÷) is working as the room name

Wow Jack, always making my life difficult…

@jayeshmangwani’s proposal looks good to me. Let’s add some more test cases in ValidationUtilsTest. 🎀 👀 🎀 C+ reviewed

@0xmiroslav Thanks for the review. For the above two questions, I would say:

1. For \p{Ll} includes all the latin lowercase letters I have checked from this source and checked from this source where it stated that {Ll} stands for a lowercase letter that has an uppercase variant

2. For checking the accented characters, we are using this range à-ÿ, which includes the 224 - 255 char code, checked on these two platforms: https://regex101.com/ and https://regexr.com/.

https://regexr.com/

https://regex101.com/

And checked the 224 - 255 char code from this source manually, and only one character(divide sign) is not the letter.

Proposal by: @jayeshmangwani Slack conversation: https://expensify.slack.com/archives/C049HHMV9SM/p1696336839411529

Proposal

Please re-state the problem that we are trying to solve in this issue.

Entering division sign (÷) is not showing any error for the room name

What is the root cause of that problem?

We are using /^#[a-z0-9à-ÿ-]{1,80}$/ regex for validating the room name https://github.com/Expensify/App/blob/00933e121f0952b7d1c2a3d577a04d2acc208de8/src/CONST.ts#L1226

To specific, checking the Latin character we are using this à-ÿ range, in the above regex

à-ÿ matches a single character in the range between à (index 224) and ÿ (index 255) (case sensitive)

so any character that has code in between 224 to 255 will be acceptable,

Divide sign character code is 247, (reference https://www.htmlhelp.com/reference/charset/iso224-255.html ) that’s why its valid character per the used regex

What changes do you think we should make in order to solve the problem?

I would suggest that we need to update the ROOM_NAME regex to that use Latin Script unicode instead of à-ÿ range

\p{Ll} will include the all the latin characters in lowercase

- ROOM_NAME: /^#[a-z0-9à-ÿ-]{1,80}$/
+ ROOM_NAME: /^[\p{Ll}0-9-]{1,80}$/u

What alternative solutions did you explore? (Optional)

Either we can remove the à-ÿ range and rather we should pass the Spanish accents á, é, í, ó, ú, ñ, ü

then regex will look like this

    ROOM_NAME: /^#[a-z0-9áéíóúñü-]{1,80}$/