No string parsing for inf/nan

noParseFloatInfOrNan.ql

/**
 * @name Use math.inf or math.nan
 * @description Prefer using math.inf instead of parsing infinity
	from a string
 * @kind problem
 * @tags maintainability
 * @problem.severity recommendation
 * @sub-severity low
 * @precision high
 * @id py/no-float-inf
 */
import python

from Call call
where call.getFunc().pointsTo(Value::named("float"))
and exists(StrConst parsedStr | parsedStr = call.getAPositionalArg()
	and (
      parsedStr.getText().toLowerCase() = "inf"
      or parsedStr.getText().toLowerCase() = "-inf"
      or parsedStr.getText().toLowerCase() = "+inf"
      or parsedStr.getText().toLowerCase() = "infinity"
      or parsedStr.getText().toLowerCase() = "+infinity"
      or parsedStr.getText().toLowerCase() = "-infinity"
 	    or parsedStr.getText().toLowerCase() = "nan"
    ))
select call, "Use `math.inf` or `math.nan` instead of parsing with `float()`."