cleanup for review

[ci skip-rust]

[ci skip-build-wheels]

src/python/pants/bin/local_pants_runner.py

@@ -4,7 +4,7 @@
 import logging
 import os
 from dataclasses import dataclass, replace
-from typing import Mapping, Optional, Set, Tuple
+from typing import List, Mapping, Optional, Tuple
 
 from pants.base.build_environment import get_buildroot
 from pants.base.exception_sink import ExceptionSink
@@ -56,7 +56,7 @@ class LocalPantsRunner:
     union_membership: UnionMembership
     profile_path: Optional[str]
     _run_tracker: RunTracker
-    _session_lifecycle_handlers: Set[SessionLifecycleHandler]
+    _session_lifecycle_handlers: List[SessionLifecycleHandler]
 
     @classmethod
     def parse_options(
@@ -168,7 +168,9 @@ def create(
         # for this session.
         session_lifecycle_handlers = []
         for lifecycle_handler in build_config.lifecycle_handlers:
-            session_lifecycle_handler = lifecycle_handler.on_session_create(options)
+            session_lifecycle_handler = lifecycle_handler.on_session_create(
+                build_root=build_root, options=options, specs=specs
+            )
             if session_lifecycle_handler:
                 session_lifecycle_handlers.append(session_lifecycle_handler)
 
@@ -298,6 +300,6 @@ def run(self, start_time: float) -> ExitCode:
 
                 # Invoke the session lifecycle handlers, if any.
                 for session_lifecycle_handler in self._session_lifecycle_handlers:
-                    session_lifecycle_handler.on_session_end()
+                    session_lifecycle_handler.on_session_end(engine_result=engine_result)
 
             return self._merge_exit_codes(engine_result, run_tracker_result)

src/python/pants/build_graph/build_configuration.py

@@ -166,7 +166,9 @@ def register_target_types(
                 )
             self._target_types.update(target_types)
 
-        def register_lifecycle_handlers(self, handlers: typing.Iterable[ExtensionLifecycleHandler]):
+        def register_lifecycle_handlers(
+            self, handlers: Union[typing.Iterable[ExtensionLifecycleHandler], typing.Any]
+        ):
             if not isinstance(handlers, Iterable):
                 raise TypeError(
                     f"The entrypoint `lifecycle_handlers` must return an iterable. Given {repr(handlers)}"

src/python/pants/build_graph/build_configuration_test.py

@@ -2,10 +2,14 @@
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
 import unittest
+from typing import Optional
 
+from pants.base.specs import Specs
 from pants.build_graph.build_configuration import BuildConfiguration
 from pants.build_graph.build_file_aliases import BuildFileAliases
+from pants.build_graph.lifecycle import ExtensionLifecycleHandler, SessionLifecycleHandler
 from pants.engine.unions import UnionRule, union
+from pants.option.options import Options
 from pants.util.frozendict import FrozenDict
 from pants.util.ordered_set import FrozenOrderedSet
 
@@ -64,3 +68,31 @@ class B:
         self.bc_builder.register_rules([union_a])
         self.bc_builder.register_rules([union_b])
         assert self.bc_builder.create().union_rules == FrozenOrderedSet([union_a, union_b])
+
+    def test_register_lifecycle_handlers(self) -> None:
+        class FooHandler(ExtensionLifecycleHandler):
+            def on_session_create(
+                self,
+                *,
+                build_root: str,
+                options: Options,
+                specs: Specs,
+            ) -> Optional[SessionLifecycleHandler]:
+                return None
+
+        class BarHandler(ExtensionLifecycleHandler):
+            def on_session_create(
+                self,
+                *,
+                build_root: str,
+                options: Options,
+                specs: Specs,
+            ) -> Optional[SessionLifecycleHandler]:
+                return None
+
+        self.bc_builder.register_lifecycle_handlers([FooHandler()])
+        self.bc_builder.register_lifecycle_handlers([BarHandler()])
+        bc = self.bc_builder.create()
+        handlers = list(bc.lifecycle_handlers)
+        assert isinstance(handlers[0], FooHandler)
+        assert isinstance(handlers[1], BarHandler)

src/python/pants/build_graph/lifecycle.py

@@ -2,18 +2,22 @@
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 from typing import Optional
 
+from pants.base.exiter import ExitCode
+from pants.base.specs import Specs
 from pants.option.options import Options
 
 
 class SessionLifecycleHandler:
     def on_session_start(self):
         pass
 
-    def on_session_end(self):
+    def on_session_end(self, *, engine_result: ExitCode):
         pass
 
 
 class ExtensionLifecycleHandler:
     # Returns a SessionLifecycleHandler that will receive lifecycle events for the session.
-    def on_session_create(self, options: Options) -> Optional[SessionLifecycleHandler]:
+    def on_session_create(
+        self, *, build_root: str, options: Options, specs: Specs
+    ) -> Optional[SessionLifecycleHandler]:
         pass

src/python/pants/core/register.py

@@ -5,9 +5,7 @@
 
 These are always activated and cannot be disabled.
 """
-from typing import Optional
 
-from pants.build_graph.lifecycle import ExtensionLifecycleHandler, SessionLifecycleHandler
 from pants.core.goals import binary, fmt, lint, package, repl, run, test, typecheck
 from pants.core.target_types import ArchiveTarget, Files, GenericTarget, RelocatedFiles, Resources
 from pants.core.target_types import rules as target_type_rules
@@ -22,7 +20,6 @@
     stripped_source_files,
     subprocess_environment,
 )
-from pants.option.options import Options
 from pants.source import source_root
 
 
@@ -54,25 +51,3 @@ def rules():
 
 def target_types():
     return [ArchiveTarget, Files, GenericTarget, Resources, RelocatedFiles]
-
-
-import logging
-logger = logging.getLogger(__name__)
-
-
-class CoreSessionLifecycleHandler(SessionLifecycleHandler):
-    def on_session_start(self):
-        logger.info("on_session_start")
-
-    def on_session_end(self):
-        logger.info("on_session_end")
-
-
-class CoreLifecycleHandler(ExtensionLifecycleHandler):
-    def on_session_create(self, options: Options) -> Optional[SessionLifecycleHandler]:
-        logger.info("on_session_create")
-        return CoreSessionLifecycleHandler()
-
-
-def lifecycle_handlers():
-    return [CoreLifecycleHandler()]