Wrong conversion from grams to kilograms in hops input

[renato]

I've been using the .deb downloaded version so far, but today I tried the repository version. This bug happens on both branches (master and stable/2.2.0).

When trying to input an amount that has 1g precision in the hop amount field, Brewtarget automatically converts the input value to kilograms.

Multiples of 10 (10, 20, 30...) are accepted, anything else is converted to kilograms (1, 5, 7, 9, 15, 44, etc).

[rocketman768]

Is is "5" or "5g" or "5 g" or something else that gets converted to 5 kg?

Also, is this happening in the hops tab or somewhere else?

[renato]

"5", "5g", "5 g", all of them get converted to 5 kg.

When I type "10", it gets converted to 10 kg. But "10g" and "10 g" are correctly accepted.

I'm talking about the Hops tab, where I assume should consider grams automatically, as a kilogram hop use is unlikely for homebrewers.

[rocketman768]

I'm curious what is the result when you right click the "Amount" then select Scale->Grams.

[renato]

With the "Default" Scale set, I typed 5g and got 5kg. Then I changed to Grams and it showed as "5.000,000 g". Typing "5", "5g" or "5 g" gives me, again, "5.000,000 g".

[renato]

I tried debugging the situation and realized that the value in the database is correct.

In https://github.com/Brewtarget/brewtarget/blob/master/src/hop.cpp#L299, get("amount") returns "0.005" kilograms, correctly.

Brewtarget::toDouble() converts it to "5", because it uses QLocale.toDouble(): https://github.com/Brewtarget/brewtarget/blob/master/src/brewtarget.cpp#L1069 and I'm using "pt_BR.UTF-8", which uses period as thousands separator and comma as decimal separator.

I commented out the QLocale.toDouble(), going straight to text.toDouble(), and the values are correctly shown.

This problem isn't reproducible with LC_ALL=en_US.UTF-8.

Even when the problem doesn't happen (using en_US, for instance), I need to type "5g" for 5 grams, otherwise Brewtarget sets the amount to 5 kg. As a suggestion, I don't think one would use kg for hops amount for any batch <1000L, so it shouldn't be the default input.

[renato]

So @rocketman768, do we need the QLocale.toDouble()? It is the reason "0.005" is becoming "5". Any reason not to go straight to QString.toDouble()?

[rocketman768]

Code to force the problem

double Brewtarget::toDouble(QString text, bool* ok)
{
   double ret = 0.0;
   bool success = false;
   // Option 1
   //QLocale sysDefault(QLocale::English, QLocale::UnitedStates);
   // Option 2
   QLocale sysDefault(QLocale::Portuguese, QLocale::Brazil);

   ret = sysDefault.toDouble(text,&success);

   qDebug() << "text: " << text << " success: " << success << " ret: " << ret;
   ...
}

Procedure

Enter "3 g" into the field.

Option 1: en_US

text: "0.003" success: true ret: 0.003

Option 2: pt_BR

text: "0.003" success: true ret: 3

Analysis

Each time, the string "0.003" is being passed into toDouble() as an unlocalized string. Need to find where this string originates and either localize it there, or use QString::toDouble() in this situation.

[rocketman768]

Found the problem, and it's a big one, so thank you very much Renato!

double Hop::amount_kg()          const { return Brewtarget::toDouble(get("amount").toString(), "Hop::amount_kg()"); }

This is just supposed to return a simple double but the Brewtarget::toDouble is a localized conversion now. I changed it to the following, and it works

double Hop::amount_kg()          const { return get("amount").toDouble(); }

This needs to be done for all the double properties of all the ingredient classes.

[rocketman768]

@renato can you see if the pull request #71 fixes the issue for you?

[renato]

@rocketman768 It does, thank you very much.

The only thing still subject to improvement in amounts input, IMHO, is the "default by type". I mean, the defaults are Kg and L, which works for fermentables or overall batch volumes, but not for hops (which are probably in grams), miscellaneous or yeasts. Of course needing to type the unit is not a big deal, but it is something to think of for future improvements.