[skip ci] Use a real unstructured grid for the test

Instead of generating gmsh files for a structured grid we use a real
unstructured grid.

test/sumfact/poisson/facedir-facemod-variation/generate_meshfiles.py

@@ -20,7 +20,7 @@ c1_5 = [3,6,12,9,2,5,11,8]
 c0s = [c0_0, c0_1, c0_2, c0_3, c0_4, c0_5]
 c1s = [c1_0, c1_1, c1_2, c1_3, c1_4, c1_5]
 
-begin = """$MeshFormat
+begin_structured = """$MeshFormat
 2.0 0 8
 $EndMeshFormat
 $Nodes
@@ -41,20 +41,46 @@ $EndNodes
 $Elements
 2
 """
+
+begin_transformed = """$MeshFormat
+2.0 0 8
+$EndMeshFormat
+$Nodes
+12
+1 0.5 0 0
+2 1 1 1
+3 1.5 2 2
+4 0 1 0
+5 0.5 2 1
+6 1 3 2
+7 0 -1 1
+8 0.5 0 2
+9 1 1 3
+10 -0.5 0 1
+11 0 1 2
+12 0.5 2 3
+$EndNodes
+$Elements
+2
+"""
+
 end = """
 $EndElements
 """
 
+filenames = ("grid_structured", "grid_transformed")
+begins = (begin_structured, begin_transformed)
 from itertools import product
-for i, c in enumerate(product(c0s, c1s)):
-    with open('grid_{}.msh'.format(str(i).zfill(2)), 'w+') as f:
-        f.write(begin)
-        f.write('1 5 0')
-        for a in c[0]:
-            f.write(' {}'.format(a))
-        f.write('\n')
-        f.write('2 5 0')
-        for a in c[1]:
-            f.write(' {}'.format(a))
-
-        f.write(end)
+for name, begin in zip(filenames, begins):
+    for i, c in enumerate(product(c0s, c1s)):
+        with open('{}_{}.msh'.format(name, str(i).zfill(2)), 'w+') as f:
+            f.write(begin)
+            f.write('1 5 0')
+            for a in c[0]:
+                f.write(' {}'.format(a))
+            f.write('\n')
+            f.write('2 5 0')
+            for a in c[1]:
+                f.write(' {}'.format(a))
+
+            f.write(end)