sjbarag / brs

An interpreter for the BrightScript language that runs on non-Roku platforms.
MIT License
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Invalid check when on the left side does not work (boxing issue) #680

Open lvcabral opened 1 year ago

lvcabral commented 1 year ago

The code below exemplifies the issue, when invalid is used on the left side of the test it is not boxed in roInvalid so is not correctly compared with the parameter (that was boxed because of the object type on the argument).

sub main()
  myVar = invalid
  RightInvalid(myVar)
  LeftInvalid(myVar)
end sub

sub RightInvalid(param1 as object)
  if param1 <> invalid
     param1.id = 1
  else
     print "param invalid"
  end if
end sub

sub LeftInvalid(param1 as object)
  if invalid <> param1
     param1.id = 1
  else
     print "param invalid"
  end if
end sub

The code was supposed to print param invalid in two consecutive lines, instead it shows the error below, because the comparison cannot say invalid is not different than roInvalid:

param invalid
left-invalid-error.brs(17,12-14): Attempting to set property on non-iterable value
    left: Object