feat: add explicit activate context manager

beet/toolchain/context.py

@@ -8,6 +8,7 @@
 
 
 import sys
+from contextlib import contextmanager
 from dataclasses import dataclass, field
 from pathlib import Path
 from typing import Any, Callable, Optional, Tuple, TypeVar
@@ -73,22 +74,25 @@ def inject(self, cls: Callable[["Context"], InjectedType]) -> InjectedType:
         """Retrieve the instance provided by the specified service factory."""
         return self._container[cls]
 
-    def __enter__(self) -> "Context":
+    @contextmanager
+    def activate(self):
         sys.path.append(self._path_entry)
-        return self
 
-    def __exit__(self, *_):
-        sys.path.remove(self._path_entry)
-
-        imported_modules = [
-            name
-            for name, module in sys.modules.items()
-            if (filename := getattr(module, "__file__", None))
-            and filename.startswith(self._path_entry)
-        ]
-
-        for name in imported_modules:
-            del sys.modules[name]
+        try:
+            with self.cache:
+                yield self.inject(Pipeline)
+        finally:
+            sys.path.remove(self._path_entry)
+
+            imported_modules = [
+                name
+                for name, module in sys.modules.items()
+                if (filename := getattr(module, "__file__", None))
+                and filename.startswith(self._path_entry)
+            ]
+
+            for name in imported_modules:
+                del sys.modules[name]
 
     @property
     def packs(self) -> Tuple[ResourcePack, DataPack]:

beet/toolchain/project.py

@@ -17,7 +17,7 @@
 from beet.core.watch import DirectoryWatcher, FileChanges
 
 from .config import PackConfig, ProjectConfig, load_config, locate_config
-from .context import Context, Pipeline, Plugin
+from .context import Context, Plugin
 from .pipeline import PipelineFallthroughException
 from .template import TemplateManager
 from .utils import locate_minecraft
@@ -211,9 +211,9 @@ def build(self) -> Context:
             ),
         )
 
-        with ctx, ctx.cache:
-            ctx.require(self.bootstrap)
-            ctx.inject(Pipeline).run(
+        with ctx.activate() as pipeline:
+            pipeline.require(self.bootstrap)
+            pipeline.run(
                 (
                     item
                     if isinstance(item, str)