Assert Receiver.ready() is called before calls to consume()

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

src/frequenz/channels/anycast.py

@@ -192,10 +192,9 @@ def consume(self) -> T:
         Returns:
             The next value that was received.
         """
-        if self._next is None:
-            raise EOFError(
-                "`consume()` was called before a call to `ready()` finished."
-            )
+        assert (
+            self._next is not None
+        ), "calls to `consume()` must be follow a call to `ready()`"
         next_val = self._next
         self._next = None
         return next_val

src/frequenz/channels/broadcast.py

@@ -275,6 +275,7 @@ def consume(self) -> T:
         Returns:
             The next value that was received.
         """
+        assert self._q, "calls to `consume()` must be follow a call to `ready()`"
         ret = self._q.popleft()
         return ret
 

src/frequenz/channels/merge.py

@@ -83,7 +83,6 @@ def consume(self) -> T:
         Returns:
             The next value that was received.
         """
-        if not self._results:
-            raise EOFError("`consume` called before `ready` finished.")
+        assert self._results, "calls to `consume()` must be follow a call to `ready()`"
 
         return self._results.popleft()

src/frequenz/channels/merge_named.py

@@ -70,7 +70,6 @@ def consume(self) -> Tuple[str, T]:
         Returns:
             The next value that was received, along with its name.
         """
-        if not self._results:
-            raise EOFError("_get called before _ready finished.")
+        assert self._results, "calls to `consume()` must be follow a call to `ready()`"
 
         return self._results.popleft()

src/frequenz/channels/utils/file_watcher.py

@@ -88,6 +88,7 @@ def consume(self) -> pathlib.Path:
         Returns:
             The next change that was received.
         """
+        assert self._changes, "calls to `consume()` must be follow a call to `ready()`"
         change = self._changes.pop()
         # Tuple of (Change, path) returned by watchfiles
         if change is None or len(change) != 2:

src/frequenz/channels/utils/timer.py

@@ -118,8 +118,9 @@ def consume(self) -> datetime:
             * **v0.11.0:** Returns a timezone-aware datetime with UTC timezone
               instead of a native datetime object.
         """
-        if self._now is None:
-            raise EOFError("`consume` called before `ready` finished")
+        assert (
+            self._now is not None
+        ), "calls to `consume()` must be follow a call to `ready()`"
         now = self._now
         self._now = None
         return now