From d1b07c625fc5ac474964e25eb988b4f829280cee Mon Sep 17 00:00:00 2001
From: Tyler Goodlet <jgbt@protonmail.com>
Date: Sat, 26 Nov 2022 15:08:36 -0500
Subject: [PATCH] Copy timestamps from source to FSP dest buffer

Slice up to history's length worth of (latest) time stamps from source
series read at the start of the history init phase.
---
 piker/fsp/_engine.py | 25 ++++++++++++++++---------
 piker/fsp/_volume.py |  3 +--
 2 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/piker/fsp/_engine.py b/piker/fsp/_engine.py
index edef7219..357934d8 100644
--- a/piker/fsp/_engine.py
+++ b/piker/fsp/_engine.py
@@ -112,8 +112,9 @@ async def fsp_compute(
         flume.rt_shm,
     )
 
-    # Conduct a single iteration of fsp with historical bars input
-    # and get historical output
+    # HISTORY COMPUTE PHASE
+    # conduct a single iteration of fsp with historical bars input
+    # and get historical output, pack into 
     history_output: Union[
         dict[str, np.ndarray],  # multi-output case
         np.ndarray,  # single output case
@@ -130,7 +131,8 @@ async def fsp_compute(
     # each respective field.
     fields = getattr(dst.array.dtype, 'fields', None).copy()
     fields.pop('index')
-    history: Optional[np.ndarray] = None  # TODO: nptyping here!
+    history_by_field: Optional[np.ndarray] = None
+    src_time = src.array['time']
 
     if (
         fields and
@@ -146,7 +148,7 @@ async def fsp_compute(
             if key in history_output:
                 output = history_output[key]
 
-                if history is None:
+                if history_by_field is None:
 
                     if output is None:
                         length = len(src.array)
@@ -156,7 +158,7 @@ async def fsp_compute(
                     # using the first output, determine
                     # the length of the struct-array that
                     # will be pushed to shm.
-                    history = np.zeros(
+                    history_by_field = np.zeros(
                         length,
                         dtype=dst.array.dtype
                     )
@@ -164,7 +166,7 @@ async def fsp_compute(
                 if output is None:
                     continue
 
-                history[key] = output
+                history_by_field[key] = output
 
     # single-key output stream
     else:
@@ -173,11 +175,13 @@ async def fsp_compute(
                 f'`{func_name}` is a single output FSP and should yield an '
                 '`np.ndarray` for history'
             )
-        history = np.zeros(
+        history_by_field = np.zeros(
             len(history_output),
             dtype=dst.array.dtype
         )
-        history[func_name] = history_output
+        history_by_field[func_name] = history_output
+
+    history_by_field['time'] = src_time[-len(history_by_field):]
 
     # TODO: XXX:
     # THERE'S A BIG BUG HERE WITH THE `index` field since we're
@@ -194,7 +198,10 @@ async def fsp_compute(
 
     # TODO: can we use this `start` flag instead of the manual
     # setting above?
-    index = dst.push(history, start=first)
+    index = dst.push(
+        history_by_field,
+        start=first,
+    )
 
     profiler(f'{func_name} pushed history')
     profiler.finish()
diff --git a/piker/fsp/_volume.py b/piker/fsp/_volume.py
index b5456fac..b998c67b 100644
--- a/piker/fsp/_volume.py
+++ b/piker/fsp/_volume.py
@@ -268,8 +268,7 @@ async def flow_rates(
         'dark_dvlm_rate': None,
     }
 
-    # TODO: 3.10 do ``anext()``
-    quote = await source.__anext__()
+    quote = await anext(source)
 
     # ltr = 0
     # lvr = 0