| 7 | |

| 8 | ------------------- details ------------- |

| 9 | |

| 10 | the patch is: |

| 11 | {{{ |

| 12 | --- a/src/sage/combinat/designs/incidence_structures.py |

| 13 | +++ b/src/sage/combinat/designs/incidence_structures.py |

| 14 | @@ -419,7 +419,7 @@ class IncidenceStructure(object): |

| 15 | sage: PP = designs.ProjectivePlaneDesign(4) |

| 16 | sage: PP.dual_design().is_block_design() |

| 17 | (True, [2, 21, 5, 1]) |

| 18 | - sage: PP = designs.ProjectivePlaneDesign(4, algorithm="gap") # optional - gap_design |

| 19 | + sage: PP = designs.ProjectiveGeometryDesign(2,1,GF(4,'conway'), algorithm="gap") # optional - gap_design |

| 20 | sage: PP.dual_design().is_block_design() # optional - gap_design |

| 21 | (True, [2, 21, 5, 1]) |

| 22 | }}} |

| 23 | without it, the test |

| 24 | {{{ |

| 25 | sage -t --long --optional=sage,gap_design src/sage/combinat/designs/incidence_structures.py |

| 26 | }}} |

| 27 | fails. |