GROOVY-8678: allow floating point literals without leading zeroes

[nineninesevenfour]

fixes https://issues.apache.org/jira/browse/GROOVY-8678

Signed-off-by: Harald Fassler harald.fassler+9974@gmail.com

[daniellansun]

+1
/cc @paulk-asert

[paulk-asert]

+1

I was worried that some of Groovy's special method/property naming capabilities might cause some conflicts but there doesn't seem to be any issues.

The following examples are unchanged:

class Test {
  def '42'() {
    println 'foo'
  }
  def '42d'() {
    println 'bing'
  }
  def get42() {
    println 'bar'
  }
  def get42f() {
    println 'baz'
  }
  def call(arg) {
    println "Arg: $arg"
  }
}

def u = new Test()
u.'42'()   // => foo
u
.'42'()    // => foo
u.'42'     // => bar
u.'42f'    // => baz
u.'42d'()  // => bing

Currently variants without the single quotes all fail parsing:

// u.42f    // Unexpected input: 'u.42f'
// u.42     // Unexpected input: 'u.42'
// u.42()   // Unexpected input: 'u.42'
// u.42f()  // Unexpected input: 'u.42f'
// u.42d()  // Unexpected input: 'u.42d'

With the changes plus the following additional line:

BigDecimal.metaClass.call << { delegate * 2 }

These now all parse with the number being a parameter to the "u" receiver's call method:

u.42f    // equivalent to u(0.42f) => Arg: 0.42
u.42     // => Arg: 0.42
u .42    // => Arg: 0.42
u.42()   // equivalent to u(0.42G.call())=> Arg: 0.84
try {
  u.42f()  // or u.42d() for Double.call
} catch(MissingMethodException mme) {
  println mme.message // => No signature of method: java.lang.Float.call() is applicable ...
}

Some might find these strange but they all make sense and might be useful in some DSL scenarios.

Certainly the error for the script _0.0g is now stranger:

MME: No signature of method: ConsoleScript10._0() is applicable for argument types: (BigDecimal) values: [0.0]

rather than Unexpected input: '_0.0g'.

The only suggestion I had was whether it would be good to see an example of the new style in the doco.
Perhaps add something like assert .5 == new BigDecimal('.5') after:
https://github.com/apache/groovy/blob/master/src/spec/test/SyntaxTest.groovy#L113

[nineninesevenfour]

I am very sorry, obviously I clicked the wrong thing 🙈 :)

[nineninesevenfour]

It seems the requested changes are empty, I cannot accept them.
Is there something open for me to do?

[paulk-asert]

Apologies, there was a glitch in my cut-n-paste and I didn't spot it straight away. Should be fixed now. There is just one line I was suggesting to add to doco plus see single line comment below.

[nineninesevenfour]

@paulk-asert I added what you suggested. Thank you for the review!

[paulk-asert]

Merged, thanks!