Refactor shift constraints in tests to use new constraint classes

- Updated test cases in `test_workers.py` to replace dictionary-based constraints with instances of `PreShiftConstraint`, `PostShiftConstraint`, and `MaxShiftsPerWeekConstraint`.
- Added a new test `test_worker_assign_as_block_preference2` to verify worker preferences for block assignments.
- Marked tests as slow where appropriate to improve test suite performance.

test/test_workers.py

@@ -1,9 +1,10 @@
 import pytest
-from rota.shifts import InvalidShift, NoWorkers, RotaBuilder, SingleShift, WarningTermination, WorkerRequirement, days
+from rota.shifts import InvalidShift, MaxShiftsPerWeekConstraint, NoWorkers, PostShiftConstraint, RotaBuilder, SingleShift, WarningTermination, WorkerRequirement, days
 
 import datetime
 from rota.workers import NonWorkingDays, NotAvailableToWork, Worker, generate_not_available_to_works
 from rota.workers import WorkRequests
+from web.rota.shifts import PreShiftConstraint
 
 def generate_basic_rota(
     weeks_to_rota=10, workers=0, start_date=datetime.date(2022, 3, 7)
@@ -577,9 +578,9 @@ def test_worker_requirement_and_force_block():
             days=days[:4],
             workers_required=wr,
             force_as_block=True,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
         SingleShift(
@@ -589,9 +590,9 @@ def test_worker_requirement_and_force_block():
             days=days[4:],
             workers_required=wr,
             force_as_block=True,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
     )
@@ -606,6 +607,7 @@ def test_worker_requirement_and_force_block():
         assert shift_string.count("cccc") == shift_string.count("c") / 4
         assert shift_string.count("ddd") == shift_string.count("d") / 3
 
+@pytest.mark.slow
 def test_split_shift():
     Rota = generate_basic_rota(workers=11, weeks_to_rota=22)
 
@@ -620,10 +622,10 @@ def test_split_shift():
             length=12.5,
             days=days[:4],
             workers_required=1,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
-            {"name": "max_shifts_per_week", "options": 1},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
+                MaxShiftsPerWeekConstraint(max_shifts=1),
             ]
         ),
         SingleShift(
@@ -633,9 +635,9 @@ def test_split_shift():
             days=(days[4], days[6]),
             workers_required=1,
             assign_as_block=True,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
         SingleShift(
@@ -644,9 +646,9 @@ def test_split_shift():
             length=12.5,
             days=days[5],
             workers_required=1,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
     )
@@ -685,7 +687,7 @@ def test_locums_basic():
             days=days[:4],
             workers_required=1,
             
-            constraint=[
+            constraints=[
             #{"name": "pre", "options": 1},
             #{"name": "post", "options": 1},
             #{"name": "max_shifts_per_week", "options": 1},
@@ -734,7 +736,7 @@ def test_locums_nwds():
             days=days[:4],
             workers_required=1,
             
-            constraint=[
+            constraints=[
             #{"name": "pre", "options": 1},
             #{"name": "post", "options": 1},
             #{"name": "max_shifts_per_week", "options": 1},
@@ -751,7 +753,6 @@ def test_locums_nwds():
     assert Rota.results.solver.status == "ok"
 
     for worker in Rota.get_workers():
-        print(  Rota.get_worker_shift_list(worker))
         assert Rota.get_worker_shift_list(worker).count("a") == 4
 
         if worker.name in ("worker03", "worker04"):
@@ -782,7 +783,7 @@ def test_locums_no_availablity():
             days=days[:4],
             workers_required=1,
             
-            constraint=[
+            constraints=[
             #{"name": "pre", "options": 1},
             #{"name": "post", "options": 1},
             #{"name": "max_shifts_per_week", "options": 1},
@@ -794,6 +795,7 @@ def test_locums_no_availablity():
     with pytest.raises(WarningTermination):
         Rota.build_and_solve()
 
+@pytest.mark.slow
 def test_locums():
     Rota = generate_basic_rota(workers=7, weeks_to_rota=10)
 
@@ -832,10 +834,10 @@ def test_locums():
             days=days[:4],
             workers_required=1,
             
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
-            {"name": "max_shifts_per_week", "options": 1},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
+                MaxShiftsPerWeekConstraint(max_shifts=1),
             ]
         ),
         SingleShift(
@@ -845,9 +847,9 @@ def test_locums():
             days=(days[4], days[6]),
             workers_required=1,
             assign_as_block=True,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
         SingleShift(
@@ -856,9 +858,9 @@ def test_locums():
             length=12.5,
             days=days[5],
             workers_required=1,
-            constraint=[
-            {"name": "pre", "options": 2},
-            {"name": "post", "options": 3},
+            constraints=[
+                PreShiftConstraint(days=2),
+                PostShiftConstraint(days=3),
             ]
         ),
     )
@@ -912,11 +914,37 @@ def test_worker_assign_as_block_preference():
     shift_list_4 = Rota.get_worker_shift_list_string(worker4)
     assert shift_list_4.count("a") == 12, "Worker 4 should have at least 12 'a' shifts, but may not be grouped together"
 
+
+def test_worker_assign_as_block_preference2():
+    """Test that a worker's assign_as_block preference is respected over the global setting."""
+    Rota = generate_basic_rota(workers=4, weeks_to_rota=8)
+
+    # Worker 1 prefers to have shift 'a' assigned as a block, worker 2 does not
+    workers = Rota.get_workers()
+    worker1 = workers[0]
+    worker2 = workers[1]
+    worker3 = workers[2]
+    worker4 = workers[3]
+
+
+    # Add a shift 'a' that is NOT globally set as assign_as_block
+    Rota.add_shifts(
+        SingleShift(
+            sites=("group1",),
+            name="a",
+            length=8,
+            days=days[:4],
+            workers_required=1,
+            assign_as_block=False,  # global setting is off
+        ),
+    )
+
     # Modify worker1's preference to prevent block 'a' shifts
     worker1.assign_as_block_preferences = {"a":-1}
     Rota.build_and_solve(options={"ratio": 0.0})
+    Rota.export_rota_to_html("test_worker_assign_as_block_preference", folder="tests")
     shift_list_1 = Rota.get_worker_shift_list_string(worker1)
-    assert shift_list_1.count("aaaa") == 0, "Worker 1 should have all 'a' shifts grouped together (block)"
+    assert shift_list_1.count("aaaa") == 0, "Worker 1 should have less 'a' shifts grouped together (block)"
 
     worker1.assign_as_block_preferences = {"a":0}