Merge branch 'main' into absolute-imports

bw2data/project.py

@@ -5,13 +5,14 @@
 from pathlib import Path
 from typing import Optional
 
-import wrapt
 from bw_processing import safe_filename
 from peewee import SQL, BooleanField, DoesNotExist, Model, TextField
 from platformdirs import PlatformDirs
+import wrapt
 
 from bw2data import config
 from bw2data.filesystem import create_dir
+from bw2data.signals import project_changed, project_created
 from bw2data.sqlite import PickleField, SubstitutableDatabase
 from bw2data.utils import maybe_path
 
@@ -196,6 +197,7 @@ def set_current(self, name, writable=True, update=True):
         self.dataset = ProjectDataset.get(ProjectDataset.name == self._project_name)
         self._reset_meta()
         self._reset_sqlite3_databases()
+        project_changed.send(self.dataset)
 
         if not writable:
             self.read_only = True
@@ -263,6 +265,7 @@ def create_project(self, name=None, **kwargs):
             self.dataset = ProjectDataset.create(
                 data=kwargs, name=name, full_hash=full_hash
             )
+            project_created.send(self.dataset)
         create_dir(self.dir)
         for dir_name in self._basic_directories:
             create_dir(self.dir / dir_name)

bw2data/signals.py

@@ -0,0 +1,20 @@
+from blinker import signal
+
+
+project_changed = signal('bw2data.project_changed', doc="""
+Emitted when project changed, after redirecting any SQLite database references.
+
+Expected inputs:
+    * `bw2data.projects.ProjectDataset` instance
+
+No expected return value.
+""")
+
+project_created = signal('bw2data.project_created', doc="""
+Emitted when project created, but before switching to that project, and before any filesystem ops.
+
+Expected inputs:
+    * `bw2data.projects.ProjectDataset` instance
+
+No expected return value.
+""")

pyproject.toml

@@ -29,8 +29,7 @@ classifiers = [
 ]
 requires-python = ">=3.9"
 dependencies = [
-    # dependencies as strings with quotes, e.g. "foo"
-    # You can add version requirements like "foo>2.0"
+    "blinker",
     "bw2parameters",
     "bw_processing>=0.9.5",
     "fsspec",

tests/test_signals.py

@@ -0,0 +1,28 @@
+from bw2data.project import ProjectDataset, projects
+from bw2data.tests import bw2test
+from blinker import signal
+
+
+class SignalCatcher:
+    def __call__(self, arg):
+        self.arg = arg
+
+
+@bw2test
+def test_project_changed_signal():
+    subscriber = SignalCatcher()
+    signal('bw2data.project_changed').connect(subscriber)
+    projects.set_current("foo")
+
+    assert isinstance(subscriber.arg, ProjectDataset)
+    assert subscriber.arg.name == 'foo'
+
+
+@bw2test
+def test_project_created_signal():
+    subscriber = SignalCatcher()
+    signal('bw2data.project_created').connect(subscriber)
+    projects.set_current("foo")
+
+    assert isinstance(subscriber.arg, ProjectDataset)
+    assert subscriber.arg.name == 'foo'