text: import pytest
  import pathlib
  import json
  
  from align.primitive.default import DefaultCanvas
  from align.cell_fabric import Pdk
  
  mydir = pathlib.Path(__file__).resolve().parent
  pdkfile = mydir.parent.parent / 'pdks' / 'FinFET14nm_Mock_PDK' / 'layers.json'
  
  @pytest.fixture
  def setup():
      p = Pdk().load(pdkfile)
      c = DefaultCanvas(p)
      return c
  
  def test_multi_via_postprocessor_v12(setup):
      c = setup
      c.addWire( c.m12, 'a', 2, (1,-1), (13,1))
      c.addWire( c.m13, None, 1, (1,-1), (3,1))
      c.addVia(c.v12, None, 1, 2)
  
      fn = '__json_multi_via_postprocessor_v12'
  
      with open( mydir / (fn + "_cand"), "wt") as fp:
          data = c.writeJSON(fp, postprocess=True)
  
      with open( mydir / (fn + "_gold"), "rt") as fp:
          data2 = json.load( fp)
  
      assert data == data2
  