DecimalFormat Does Not Suppress Negative Sign

[mlvn23]

This test case passes in JVM but not in JS:

        val uut2 = new DecimalFormat("0.00; 0.00")
        checkEquals("7.65", uut2.format(7.65))
        checkEquals(" 7.65", uut2.format(-7.65))
        checkEquals("98765.23", uut2.format(98765.234))
        checkEquals(" 98765.23", uut2.format(-98765.234))

[cquiroz]

Thanks for the report, I tested this and you're right. Are you interested on fixing it?

[mlvn23]

Apparently, this also does not work:

        val uut0 = new DecimalFormat("000")
        checkEquals("001", uut0.format(1))

[mlvn23]

I looked at the JavaDoc and it does not look trivial to implement it from scratch. I saw a couple of implementation in JavaScript in Github. One is has MIT and another has BSD-3. Android SDK is under Apache, which might be compatible with BSD? Do you think it's okay to port it?

[cquiroz]

I agree it is not trivial, the algorithm was created by hand and obviously the parsing of the format is missing some cases.
Unfortunately I don't have time to purse this
About porting please be mindful of the scala.js rules:
https://github.com/scala-js/scala-js/blob/master/DEVELOPING.md

Essentially you can't look at jdk code or harmony

[cquiroz]

I added your example as an ignored test
https://github.com/cquiroz/scala-java-locales/blob/master/testSuite/shared/src/test/scala/testsuite/javalib/text/DecimalFormatTest.scala#L674

[mlvn23]

If you're okay with an external JS lib, this implementation appears to be good:

https://github.com/DeloitteDigitalAPAC/DecimalFormat

They did it with a formalized parser and lots of tests. It also accepts a locale as input.

I did a browserify with it and ran it in ScalaJS with some of my unit test and so far so good. I'll try to do a CI test later this week to see if it holds up.

[cquiroz]

That's interesting. I wouldn't expect a js library implementing a java spec. It maybe used I think provided it doesn't add up too much in terms of size.
I want to support scala-native so this may need to go into a js specific version

[mlvn23]

I've been using it for two weeks trying different things and it seems solid. About 14KB minimized.

[cquiroz]

That sounds great, if you want to submit a PR it would be ok, Let's keep the old version in a cross project for a future scala native release