Parse exponential float as Money

[gmponos]

Created a new Parser that will be able to parse exponential values to Money object. This solves the issue that I have presented on this PR #494

This parser is used only for exponential values and not for decimals.. It will be good to be used combined with an Aggregator parser and a decimal parser.

[gmponos]

@money-team let me know if this going to the correct direction for you in order to finalize the PR and fix the CI failures.

[frederikbosch]

@gmponos Why not inject a Decimal parser and then delegate the parsing process once you have handled the exponential part? Maybe I should have a closer look, but as it seems to me there is a lot of duplicate code?

public function __construct(Currencies $currencies, DecimalMoneyParser $delegatedParser) {
   $this->currencies = $currencies;
   $this->delegatedParser = $delegatedParser;
}

public function parse($money, $forceCurrency = null) {
   // ....
  $number = number_format($expo, $subunit, '.', '');
  return $this->delegatedParser->parse($number, $forceCurrency);
}

[gmponos]

@frederikbosch I though about the same solution too. But I dislike it for the following reasons:

1. First of all I had in mind some next steps that can be taken. It can be found here. The argument about duplication stands almost for every parser. So the next step could be using a trait in all parsers and avoiding the duplication.
2. Secondly I will need to do some checks inside exponential parser and then the same checks will be repeated inside the decimal parser. For instance:

ExponentialParser.php

    public function parse($money, $forceCurrency = null)
    {
        if (!is_string($money)) {
            throw new ParserException('Formatted raw money should be string, e.g. 1.00');
        }

        if (null === $forceCurrency) {
            throw new ParserException(
                'ExponentialParser cannot parse currency symbols. Use forceCurrency argument'
            );
        }
       ....
      $this->delegatedParser->parse(...);

The same checks above will be checked again inside the delegatedParser

3. The initialization process in order to add inside an AggregatorParser a DecimalParser and an ExponentialParser it would feel kinda odd for me...

$decimal = new DecimalParser(...);
$exponention = new ExponentialParser($decimal, $currencies);
$aggregator = new AggregatorParser([
    $decimal, 
    $exponential
])

Anyway my current solution stands to the following facts:

1. Most of the parsers already have the same code.. written a little bit differently.. check the PR above.
2. I could implement the solution directly inside DecimalParser but my solution requires to use number_format function. if I did that most probably it would raise some questions like why the DecimalParser doesn't use the number_format function on the rest of the code. And also are values like these "1.234e-11" considered "Decimals".. Playing with words here...

[sagikazarmark]

A trait indeed seems to be an easier solution in this case as the delegated parser would always be a decimal parser.

[sagikazarmark]

Looks good to me! Should wait for the trait though

[mwgamble]

Shouldn't this say "ExponentialMoneyParser", not "DecimalMoneyParser"?

[gmponos]

Done.. nice catch

[frederikbosch]

@gmponos Could you update this PR against the latest master? Sorry for our very late action on this.

[frederikbosch]

Superseded by #668.