element.py, source.py: Removing knowledge of assemble scheduling state from source

And considering the workspace related edge cases in Element instead of Source.

2 files changed, 8 insertions, 41 deletions

diff --git a/buildstream/element.py b/buildstream/element.py
index 867937115..13d13a861 100644
--- a/buildstream/element.py
+++ b/buildstream/element.py
@@ -856,8 +856,10 @@ class Element(Plugin):
         assert not self.__assemble_scheduled
         self.__assemble_scheduled = True
 
-        for source in self.__sources:
-            source._schedule_assemble()
+        # Invalidate workspace key as the build modifies the workspace directory
+        workspace = self._get_workspace()
+        if workspace:
+            workspace.invalidate_key()
 
         self._update_state()
 
@@ -871,9 +873,6 @@ class Element(Plugin):
     def _assemble_done(self):
         assert self.__assemble_scheduled
 
-        for source in self.__sources:
-            source._assemble_done()
-
         self.__assemble_scheduled = False
         self.__assemble_done = True
 
@@ -1663,9 +1662,10 @@ class Element(Plugin):
             # Tracking may still be pending
             return
 
-        if any([not source._stable() for source in self.__sources]):
-            # If any source is not stable, discard current cache key values
-            # as their correct values can only be calculated once the build is complete
+        if self._get_workspace() and self.__assemble_scheduled:
+            # If we have an active workspace and are going to build, then
+            # discard current cache key values as their correct values can only
+            # be calculated once the build is complete
             self.__cache_key_dict = None
             self.__cache_key = None
             self.__weak_cache_key = None
diff --git a/buildstream/source.py b/buildstream/source.py
index 286db5707..e6ca99735 100644
--- a/buildstream/source.py
+++ b/buildstream/source.py
@@ -88,7 +88,6 @@ class Source(Plugin):
         self.__element_index = meta.element_index       # The index of the source in the owning element's source list
         self.__directory = meta.directory               # Staging relative directory
         self.__consistency = Consistency.INCONSISTENT   # Cached consistency state
-        self.__assemble_scheduled = False               # Source is scheduled to be assembled
         self.__workspace = None                         # Directory of the currently active workspace
 
         # Collect the composited element configuration and
@@ -323,37 +322,6 @@ class Source(Plugin):
     def _get_consistency(self):
         return self.__consistency
 
-    # _schedule_assemble():
-    #
-    # This is called in the main process before the element is assembled
-    # in a subprocess.
-    #
-    def _schedule_assemble(self):
-        assert not self.__assemble_scheduled
-        self.__assemble_scheduled = True
-
-        # Invalidate workspace key as the build modifies the workspace directory
-        if self._has_workspace():
-            self.__workspace.invalidate_key()
-
-    # _assemble_done():
-    #
-    # This is called in the main process after the element has been assembled
-    # in a subprocess.
-    #
-    def _assemble_done(self):
-        assert self.__assemble_scheduled
-        self.__assemble_scheduled = False
-
-    # _stable():
-    #
-    # Unstable sources are mounted read/write and thus cannot produce a
-    # (stable) cache key before the build is complete.
-    #
-    def _stable(self):
-        # Source directory is modified by workspace build process
-        return not (self._has_workspace() and self.__assemble_scheduled)
-
     # Wrapper function around plugin provided fetch method
     #
     def _fetch(self):
@@ -406,7 +374,6 @@ class Source(Plugin):
 
         key['directory'] = self.__directory
         if self._has_workspace():
-            assert not self.__assemble_scheduled
             key['workspace'] = self.__workspace.get_key()
         else:
             key['unique'] = self.get_unique_key()