Fix unicode fraction conversion

[christianlupus]

Description
When using unicode fractions, the web UI reports the ingredient to not be parsable but in fact it is parsable and correctly calculated.

Reproduction
Steps to reproduce the behavior:

1. Create or edit a recipe
2. Add an ingredient with a unicode fraction, e.g. ¾
3. Save and view the recipe
4. Change the recipe yield to trigger recalculation

Expected behavior
No warning is shown to the user

Actual behavior
A warning sign is shown to the user indicating a problem with the calculation (see screenshots).

Screenshots

After changing the yield amount:

Browser
Firefox

Versions
Nextcloud server version: 30
Cookbook version: 0.11.1
Database system: MySQL

---

Maybe @Weissnix4711 or @j0hannesr0th, can you have a look at this? Ideally, I would say that the same Regex is used to check and to do the actual calculation to avoid such conflicts. That would mean some restructuring but should be managable.

[j0hannesr0th]

Hi @christianlupus I'll have a look at this one.

Do you want to support the common Unicode fractions or custom Unicode fractions like ⁷⁷⁄₇₈ too?

[Weissnix4711]

Uhh, maybe I fucked the regex

[christianlupus]

In the PR there was a discussion to mainly look for x/2, x/4, and x/16 as far as I remember.

I suggest you two align a bit to avoid duplicate work.

[christianlupus]

Ahh and one more point: I want to push out a release tomorrow. On Saturday there is a NC server release and we need a new cookbook version ready as otherwise these will complain.

I am okay with delaying this until after the release. Just be warned that I am not going to be able to do much about this in the next few hours. 😉

[Weissnix4711]

Yeah ideally we should probably use the same regex, but the easy solution is this:

diff --git a/src/js/yieldCalculator.js b/src/js/yieldCalculator.js
index bfe2da97..47bf75d3 100644
--- a/src/js/yieldCalculator.js
+++ b/src/js/yieldCalculator.js
@@ -11,7 +11,7 @@ function isValidIngredientSyntax(ingredient) {
         It may optionally have a unit but must be proceeded by a single whitespace and further text.
     */
     const ingredientSyntaxRegExp =
-        /^(?:(?:\d+\s)?(?:\d+\/\d+|\p{No})|\d+(?:\.\d+)?)[a-zA-z]*\s.*$/;
+        /^(?:(?:\d+\s)?(?:\d+\/\d+|\p{No})|\d+(?:\.\d+)?)[a-zA-z]*\s.*$/u;
 
     /*
         The ingredientMultipleSeperatorsRegExp is used to check whether the string contains

I missed the u flag.

[christianlupus]

Feel free to give it a go from my side. Ideally there is some error handling involved if we update the regex (for whatever reason), this is not breaking again.