Legacy code removal in pass manager

qiskit/passmanager/__init__.py

@@ -209,7 +209,6 @@ def digit_condition(property_set):
 .. autosummary::
    :toctree: ../stubs/
 
-   FlowController
    FlowControllerLinear
    ConditionalController
    DoWhileController
@@ -232,7 +231,6 @@ def digit_condition(property_set):
 
 from .passmanager import BasePassManager
 from .flow_controllers import (
-    FlowController,
     FlowControllerLinear,
     ConditionalController,
     DoWhileController,

qiskit/passmanager/flow_controllers.py

@@ -15,9 +15,8 @@
 
 import logging
 from collections.abc import Callable, Iterable, Generator
-from typing import Type, Any
+from typing import Any
 
-from qiskit.utils.deprecation import deprecate_func
 from .base_tasks import BaseController, Task
 from .compilation_status import PassManagerState, PropertySet
 from .exceptions import PassManagerError
@@ -45,31 +44,6 @@ def passes(self) -> list[Task]:
         """Alias of tasks for backward compatibility."""
         return list(self.tasks)
 
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg="All tasks must be provided at construction time of the controller object.",
-    )
-    def append(
-        self,
-        passes: Task | list[Task],
-    ):
-        """Add new task to pipeline.
-
-        Args:
-            passes: A new task or list of tasks to add.
-        """
-        if not isinstance(passes, Iterable):
-            passes = [passes]
-
-        tasks = list(self.tasks)
-        for task in passes:
-            if not isinstance(task, Task):
-                raise TypeError(
-                    f"New task {task} is not a valid pass manager pass or flow controller."
-                )
-            tasks.append(task)
-        self.tasks = tuple(tasks)
-
     def iter_tasks(self, state: PassManagerState) -> Generator[Task, PassManagerState, None]:
         for task in self.tasks:
             state = yield task
@@ -101,31 +75,6 @@ def passes(self) -> list[Task]:
         """Alias of tasks for backward compatibility."""
         return list(self.tasks)
 
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg="All tasks must be provided at construction time of the controller object.",
-    )
-    def append(
-        self,
-        passes: Task | list[Task],
-    ):
-        """Add new task to pipeline.
-
-        Args:
-            passes: A new task or list of tasks to add.
-        """
-        if not isinstance(passes, Iterable):
-            passes = [passes]
-
-        tasks = list(self.tasks)
-        for task in passes:
-            if not isinstance(task, Task):
-                raise TypeError(
-                    f"New task {task} is not a valid pass manager pass or flow controller."
-                )
-            tasks.append(task)
-        self.tasks = tuple(tasks)
-
     def iter_tasks(self, state: PassManagerState) -> Generator[Task, PassManagerState, None]:
         max_iteration = self._options.get("max_iteration", 1000)
         for _ in range(max_iteration):
@@ -161,176 +110,7 @@ def passes(self) -> list[Task]:
         """Alias of tasks for backward compatibility."""
         return list(self.tasks)
 
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg="All tasks must be provided at construction time of the controller object.",
-    )
-    def append(
-        self,
-        passes: Task | list[Task],
-    ):
-        """Add new task to pipeline.
-
-        Args:
-            passes: A new task or list of tasks to add.
-        """
-        if not isinstance(passes, Iterable):
-            passes = [passes]
-
-        tasks = list(self.tasks)
-        for task in passes:
-            if not isinstance(task, Task):
-                raise TypeError(
-                    f"New task {task} is not a valid pass manager pass or flow controller."
-                )
-            tasks.append(task)
-        self.tasks = tuple(tasks)
-
     def iter_tasks(self, state: PassManagerState) -> Generator[Task, PassManagerState, None]:
         if self.condition(state.property_set):
             for task in self.tasks:
                 state = yield task
-
-
-class FlowController(BaseController):
-    """A legacy factory for other flow controllers.
-
-    .. warning::
-
-        This class is primarily for compatibility with legacy versions of Qiskit, and in general,
-        you should prefer simply instantiating the controller you want, and adding it to the
-        relevant :class:`.PassManager` or other controller.  Its use is deprecated.
-
-    This allows syntactic sugar for writing pipelines. For example::
-
-        FlowController.add_flow_controller("my_condition", CustomController)
-
-        controller = FlowController.controller_factory(
-            [PassA(), PassB()],
-            {"max_iteration": 1000},
-            condition=lambda prop_set: prop_set["x"] == 0,
-            do_while=lambda prop_set: prop_set["x"] < 100,
-            my_condition=lambda prop_set: prop_set["y"] = "abc",
-        )
-
-    This creates a nested flow controller that runs when the value :code:`x` in the
-    :class:`.PropertySet` is zero and repeats the pipeline until the value becomes 100.
-    In each innermost loop, the custom iteration condition provided by
-    the ``CustomController`` is also evaluated.
-
-    .. warning::
-
-        :class:`.BaseController` must be directly subclassed to define a custom flow controller.
-        This class provides a controller factory method, which consumes a class variable
-        :attr:`.registered_controllers`. Subclassing FlowController may cause
-        unexpected behavior in the factory method.
-        Note that factory method implicitly determines the priority of the builtin controllers
-        when multiple controllers are called together,
-        and the behavior of generated controller is hardly debugged.
-    """
-
-    registered_controllers = {
-        "condition": ConditionalController,
-        "do_while": DoWhileController,
-    }
-    hierarchy = [
-        "condition",
-        "do_while",
-    ]
-
-    @classmethod
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg=(
-            "Controller object must be explicitly instantiated. "
-            "Building controller with keyword arguments may yield race condition when "
-            "multiple keyword arguments are provided together, which is likely unsafe."
-        ),
-    )
-    def controller_factory(
-        cls,
-        passes: Task | list[Task],
-        options: dict,
-        **controllers,
-    ):
-        """Create a new flow controller with normalization.
-
-        Args:
-            passes: A list of optimization tasks.
-            options: Option for this flow controller.
-            controllers: Dictionary of controller callables keyed on flow controller alias.
-
-        Returns:
-            An instance of normalized flow controller.
-        """
-        if None in controllers.values():
-            raise PassManagerError("The controller needs a callable. Value cannot be None.")
-
-        if isinstance(passes, BaseController):
-            instance = passes
-        else:
-            instance = FlowControllerLinear(passes, options=options)
-
-        if controllers:
-            # Alias in higher hierarchy becomes outer controller.
-            for alias in cls.hierarchy[::-1]:
-                if alias not in controllers:
-                    continue
-                class_type = cls.registered_controllers[alias]
-                init_kwargs = {
-                    "options": options,
-                    alias: controllers.pop(alias),
-                }
-                instance = class_type([instance], **init_kwargs)
-
-        return instance
-
-    @classmethod
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg=(
-            "Controller factory method is deprecated and managing the custom flow controllers "
-            "with alias no longer helps building the task pipeline. "
-            "Controllers must be explicitly instantiated and appended to the pipeline."
-        ),
-    )
-    def add_flow_controller(
-        cls,
-        name: str,
-        controller: Type[BaseController],
-    ):
-        """Adds a flow controller.
-
-        Args:
-            name: Alias of controller class in the namespace.
-            controller: Flow controller class.
-        """
-        cls.registered_controllers[name] = controller
-        if name not in cls.hierarchy:
-            cls.hierarchy.append(name)
-
-    @classmethod
-    @deprecate_func(
-        since="0.45.0",
-        additional_msg=(
-            "Controller factory method is deprecated and managing the custom flow controllers "
-            "with alias no longer helps building the task pipeline. "
-            "Controllers must be explicitly instantiated and appended to the pipeline."
-        ),
-    )
-    def remove_flow_controller(
-        cls,
-        name: str,
-    ):
-        """Removes a flow controller.
-
-        Args:
-            name: Alias of the controller to remove.
-
-        Raises:
-            KeyError: If the controller to remove was not registered.
-        """
-        if name not in cls.hierarchy:
-            raise KeyError("Flow controller not found: %s" % name)
-        del cls.registered_controllers[name]
-        cls.hierarchy.remove(name)

qiskit/transpiler/__init__.py

@@ -1231,15 +1231,6 @@
 
    InstructionDurations
 
-Fenced Objects
---------------
-
-.. autosummary::
-   :toctree: ../stubs/
-
-   FencedPropertySet
-   FencedDAGCircuit
-
 Abstract Passes
 ---------------
 
@@ -1262,22 +1253,20 @@
 
 # For backward compatibility
 from qiskit.passmanager import (
-    FlowController,
     ConditionalController,
     DoWhileController,
 )
+from qiskit.passmanager.compilation_status import PropertySet
 
 from .passmanager import PassManager, StagedPassManager
 from .passmanager_config import PassManagerConfig
-from .propertyset import PropertySet  # pylint: disable=no-name-in-module
 from .exceptions import (
     TranspilerError,
     TranspilerAccessError,
     CouplingError,
     LayoutError,
     CircuitTooWideForTarget,
 )
-from .fencedobjs import FencedDAGCircuit, FencedPropertySet
 from .basepasses import AnalysisPass, TransformationPass
 from .coupling import CouplingMap
 from .layout import Layout, TranspileLayout