Enhance hard day dependency handling with ignore dates and improve warning visibility

gen_cons.py

@@ -1,3 +1,4 @@
+from pyomo.opt.results.container import ignore
 from collections import defaultdict
 import datetime
 import os
@@ -299,7 +300,7 @@ def load_workers():
             w.add_force_assign_with("weekend", "oncall")
 
             if w.name in ("DS",):
-                w.add_hard_day_dependency({"Fri", "Sat", "Sun"})
+                w.add_hard_day_dependency({"Fri", "Sat", "Sun"}, ignore_dates=[datetime.date(2026, 5, 2)])
             else:
                 w.add_hard_day_dependency({"Fri", "Sun"})
                 w.add_hard_day_exclusion({"Sat", "Sun"})

rota_generator/shifts.py

@@ -1702,6 +1702,18 @@ class RotaBuilder(object):
                         )
 
                     for week in weeks_to_apply:
+                        # compute which days in the day_group should be ignored
+                        ignored_days = set()
+                        try:
+                            for ignore_date in getattr(dep, "ignore_dates", []) or []:
+                                try:
+                                    ww, dd = self.date_week_day_map.get(ignore_date, (None, None))
+                                except Exception:
+                                    ww = dd = None
+                                if ww == week and dd in day_group:
+                                    ignored_days.add(dd)
+                        except Exception:
+                            ignored_days = set()
                         # If the worker has any forced assignment in the dependency group,
                         # emit a concise warning. For visibility include every day in the
                         # group showing the worker's forced shifts (if any) and other
@@ -1729,6 +1741,9 @@ class RotaBuilder(object):
                                 date_map_for_week = {}
 
                             for day in day_group:
+                                if day in ignored_days:
+                                    # skip ignored dates for warning/visibility
+                                    continue
                                 worker_forced_shifts = set()
                                 # week-based forced assignments
                                 for (fw, fd, fs) in getattr(worker, "forced_assignments", []):
@@ -1799,8 +1814,14 @@ class RotaBuilder(object):
                                 "HardDayDependency forced assignment",
                                 f"Worker '{worker.name}' has hard_day_dependency {set(day_group)} in week {week}; forced assignments on dependency days: {details}. If the rota is not infeasible this is unlikely to be an issue.",
                             )
+                        # Build constraints only for non-ignored days
+                        effective_days = [d for d in day_group if d not in ignored_days]
+                        if not effective_days:
+                            # nothing to constrain for this dependency in this week
+                            continue
+
                         assigned_any_shift = {}
-                        for day in day_group:
+                        for day in effective_days:
                             shifts_today = self.get_shift_names_by_week_day(week, day)
                             var_name = f"hard_day_dep_{worker.id}_{week}_{day}"
                             if not hasattr(self.model, "hard_day_dep_vars"):
@@ -1812,7 +1833,7 @@ class RotaBuilder(object):
                             total_assigned = sum(self.model.works[worker.id, week, day, shift] for shift in shifts_today)
                             self.model.constraints.add(total_assigned >= assigned_any_shift[day])
                             self.model.constraints.add(total_assigned <= len(shifts_today) * assigned_any_shift[day])
-                        # All-or-none: all days in the group must have the same assignment status
+                        # All-or-none: all effective (non-ignored) days in the group must have the same assignment status
                         vals = list(assigned_any_shift.values())
                         for i in range(1, len(vals)):
                             self.model.constraints.add(vals[i] == vals[0])

rota_generator/workers.py

@@ -36,6 +36,7 @@ class HardDayDependency(BaseModel):
     weeks: Optional[List[int]] = None  # If None, applies to all weeks
     start_date: Optional[datetime.date] = None  # Optional start date for the dependency
     end_date: Optional[datetime.date] = None  # Optional end date for the dependency
+    ignore_dates: list[datetime.date] = Field(default_factory=list, description="List of specific dates to ignore for this dependency")
 
     @field_validator("weeks")
     def weeks_none_if_dates_set(cls, weeks, values):
@@ -437,13 +438,13 @@ class Worker(BaseModel):
             self.allowed_multi_shift_sets = []
         self.allowed_multi_shift_sets.append(frozenset(shifts))
 
-    def add_hard_day_dependency(self, days: set[str], weeks: Optional[List[int]] = None, start_date: Optional[datetime.date] = None, end_date: Optional[datetime.date] = None):
+    def add_hard_day_dependency(self, days: set[str], weeks: Optional[List[int]] = None, start_date: Optional[datetime.date] = None, end_date: Optional[datetime.date] = None, ignore_dates: Optional[List[datetime.date]] = None):
         """
         Add a hard day dependency for this worker.
         days: List of days that must be grouped together.
         weeks: Optional list of weeks this dependency applies to. If None, applies to all weeks.
         """
-        self.hard_day_dependencies.append(HardDayDependency(days=days, weeks=weeks, start_date=start_date, end_date=end_date))
+        self.hard_day_dependencies.append(HardDayDependency(days=days, weeks=weeks, start_date=start_date, end_date=end_date, ignore_dates=ignore_dates or []))
 
     def add_hard_day_exclusion(self, days: set[str], weeks: Optional[List[int]] = None, start_date: Optional[datetime.date] = None, end_date: Optional[datetime.date] = None):
         """