model: Automatically increase steps counter

benchmarks/BoltzmannWealth/boltzmann_wealth.py

@@ -38,7 +38,6 @@ def __init__(self, seed=None, n=100, width=10, height=10):
         self.datacollector.collect(self)
 
     def step(self):
-        self._advance_time()
         self.agents.shuffle().do("step")
         # collect data
         self.datacollector.collect(self)

mesa/batchrunner.py

@@ -132,14 +132,14 @@ def _model_run_func(
     """
     run_id, iteration, kwargs = run
     model = model_cls(**kwargs)
-    while model.running and model._steps <= max_steps:
+    while model.running and model.steps <= max_steps:
         model.step()
 
     data = []
 
-    steps = list(range(0, model._steps, data_collection_period))
-    if not steps or steps[-1] != model._steps - 1:
-        steps.append(model._steps - 1)
+    steps = list(range(0, model.steps, data_collection_period))
+    if not steps or steps[-1] != model.steps - 1:
+        steps.append(model.steps - 1)
 
     for step in steps:
         model_data, all_agents_data = _collect_data(model, step)

mesa/datacollection.py

@@ -180,7 +180,7 @@ def _record_agents(self, model):
         rep_funcs = self.agent_reporters.values()
 
         def get_reports(agent):
-            _prefix = (agent.model._steps, agent.unique_id)
+            _prefix = (agent.model.steps, agent.unique_id)
             reports = tuple(rep(agent) for rep in rep_funcs)
             return _prefix + reports
 
@@ -216,7 +216,7 @@ def collect(self, model):
 
         if self.agent_reporters:
             agent_records = self._record_agents(model)
-            self._agent_records[model._steps] = list(agent_records)
+            self._agent_records[model.steps] = list(agent_records)
 
     def add_table_row(self, table_name, row, ignore_missing=False):
         """Add a row dictionary to a specific table.

mesa/model.py

@@ -17,8 +17,6 @@
 from mesa.agent import Agent, AgentSet
 from mesa.datacollection import DataCollector
 
-TimeT = float | int
-
 
 class Model:
     """Base class for models in the Mesa ABM library.
@@ -35,6 +33,8 @@ class Model:
     Properties:
         agents: An AgentSet containing all agents in the model
         agent_types: A list of different agent types present in the model.
+        steps: An integer representing the number of steps the model has taken.
+               It increases automatically at the start of each step() call.
 
     Methods:
         get_agents_of_type: Returns an AgentSet of agents of the specified type.
@@ -62,10 +62,6 @@ def __new__(cls, *args: Any, **kwargs: Any) -> Any:
             # advance.
             obj._seed = random.random()
         obj.random = random.Random(obj._seed)
-
-        # TODO: Remove these 2 lines just before Mesa 3.0
-        obj._steps = 0
-        obj._time = 0
         return obj
 
     def __init__(self, *args: Any, **kwargs: Any) -> None:
@@ -77,11 +73,20 @@ def __init__(self, *args: Any, **kwargs: Any) -> None:
         self.running = True
         self.schedule = None
         self.current_id = 0
+        self.steps: int = 0
 
         self._setup_agent_registration()
 
-        self._steps: int = 0
-        self._time: TimeT = 0  # the model's clock
+        # Wrap the user-defined step method
+        self._user_step = self.step
+        self.step = self._wrapped_step
+
+    def _wrapped_step(self, *args: Any, **kwargs: Any) -> None:
+        """Automatically increments time and steps after calling the user's step method."""
+        # Automatically increment time and step counters
+        self.steps += 1
+        # Call the original user-defined step method
+        self._user_step(*args, **kwargs)
 
     @property
     def agents(self) -> AgentSet:
@@ -180,11 +185,6 @@ def run_model(self) -> None:
     def step(self) -> None:
         """A single step. Fill in here."""
 
-    def _advance_time(self, deltat: TimeT = 1):
-        """Increment the model's steps counter and clock."""
-        self._steps += 1
-        self._time += deltat
-
     def next_id(self) -> int:
         """Return the next unique ID for agents, increment current_id"""
         self.current_id += 1

mesa/time.py

@@ -69,8 +69,6 @@ def __init__(self, model: Model, agents: Iterable[Agent] | None = None) -> None:
         self.model = model
         self.steps = 0
         self.time: TimeT = 0
-        self._original_step = self.step
-        self.step = self._wrapped_step
 
         if agents is None:
             agents = []
@@ -113,11 +111,6 @@ def step(self) -> None:
         self.steps += 1
         self.time += 1
 
-    def _wrapped_step(self):
-        """Wrapper for the step method to include time and step updating."""
-        self._original_step()
-        self.model._advance_time()
-
     def get_agent_count(self) -> int:
         """Returns the current number of agents in the queue."""
         return len(self._agents)

mesa/visualization/solara_viz.py

@@ -244,7 +244,7 @@
         """Advance the model by one step."""
         model.step()
         previous_step.value = current_step.value
-        current_step.value = model._steps
+        current_step.value = model.steps
 
     def do_play():
         """Run the model continuously."""

tests/test_batch_run.py

@@ -83,8 +83,8 @@ def get_local_model_param(self):
         return 42
 
     def step(self):
-        self.datacollector.collect(self)
         self.schedule.step()
+        self.datacollector.collect(self)
 
 
 def test_batch_run():

tests/test_examples.py

@@ -66,3 +66,4 @@ def test_examples(self):
                 model = model_class()
                 for _ in range(10):
                     model.step()
+                self.assertEqual(model.steps, 10)

tests/test_model.py

@@ -9,7 +9,9 @@ def test_model_set_up():
     assert model.current_id == 0
     assert model.current_id + 1 == model.next_id()
     assert model.current_id == 1
+    assert model.steps == 0
     model.step()
+    assert model.steps == 1
 
 
 def test_running():
@@ -18,12 +20,12 @@ class TestModel(Model):
 
         def step(self):
             """Increase steps until 10."""
-            self.steps += 1
             if self.steps == 10:
                 self.running = False
 
     model = TestModel()
     model.run_model()
+    assert model.steps == 10
 
 
 def test_seed(seed=23):