code: def test_log1p_expr():
      expr = ast.Log1pExpr(ast.NumVal(2.0))
  
      expected_code = """
  def score(input)
      log1p(2.0)
  end
  def log1p(x)
      if x == 0.0
          return 0.0
      end
      if x == -1.0
          return -Float::INFINITY
      end
      if x < -1.0
          return Float::NAN
      end
      x_abs = x.abs
      if x_abs < 0.5 * Float::EPSILON
          return x
      end
      if (x > 0.0 && x < 1e-8) || (x > -1e-9 && x < 0.0)
          return x * (1.0 - x * 0.5)
      end
      if x_abs < 0.375
          coeffs = [
               0.10378693562743769800686267719098e+1,
              -0.13364301504908918098766041553133e+0,
               0.19408249135520563357926199374750e-1,
              -0.30107551127535777690376537776592e-2,
               0.48694614797154850090456366509137e-3,
              -0.81054881893175356066809943008622e-4,
               0.13778847799559524782938251496059e-4,
              -0.23802210894358970251369992914935e-5,
               0.41640416213865183476391859901989e-6,
              -0.73595828378075994984266837031998e-7,
               0.13117611876241674949152294345011e-7,
              -0.23546709317742425136696092330175e-8,
               0.42522773276034997775638052962567e-9,
              -0.77190894134840796826108107493300e-10,
               0.14075746481359069909215356472191e-10,
              -0.25769072058024680627537078627584e-11,
               0.47342406666294421849154395005938e-12,
              -0.87249012674742641745301263292675e-13,
               0.16124614902740551465739833119115e-13,
              -0.29875652015665773006710792416815e-14,
               0.55480701209082887983041321697279e-15,
              -0.10324619158271569595141333961932e-15]
          return x * (1.0 - x * chebyshev_broucke(x / 0.375, coeffs))
      end
      return Math.log(1.0 + x)
  end
  def chebyshev_broucke(x, coeffs)
      b2 = b1 = b0 = 0.0
      x2 = x * 2
      coeffs.reverse_each do |i|
          b2 = b1
          b1 = b0
          b0 = x2 * b1 - b2 + i
      end
      (b0 - b2) * 0.5
  end
  """
  
      interpreter = RubyInterpreter()
      assert_code_equal(interpreter.interpret(expr), expected_code)
  
imports: from itertools import product
  import pytest
  from m2cgen import ast
  from m2cgen.interpreters import RubyInterpreter
  from tests.utils import assert_code_equal
label_desc: Use image node_id 16 for calling a global function with example usage: test_log1p_expr() without return types