From 416d8fad221c8037e2b1941b4a0ad6760dceee93 Mon Sep 17 00:00:00 2001
From: Jim Bosch <jbosch@astro.princeton.edu>
Date: Tue, 14 Jan 2025 19:03:10 -0500
Subject: [PATCH] Use new refcat loader method to improve refcat flux field
 checks.

The new implementation no longer assumes there is a refcat shard
overlapping the center of a tract, which was important for ci_hsc.
---
 python/lsst/pipe/tasks/loadReferenceCatalog.py | 8 ++------
 tests/test_loadReferenceCatalog.py             | 8 ++++++++
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/python/lsst/pipe/tasks/loadReferenceCatalog.py b/python/lsst/pipe/tasks/loadReferenceCatalog.py
index 95b8a0fbd..6f0caac73 100644
--- a/python/lsst/pipe/tasks/loadReferenceCatalog.py
+++ b/python/lsst/pipe/tasks/loadReferenceCatalog.py
@@ -38,8 +38,6 @@
 from lsst.afw.image import abMagErrFromFluxErr
 from lsst.meas.algorithms import ReferenceObjectLoader, LoadReferenceObjectsConfig
 
-import lsst.geom
-
 
 class LoadReferenceCatalogConfig(pexConfig.Config):
     """Config for LoadReferenceCatalogTask"""
@@ -340,9 +338,7 @@ def _determineFluxFields(self, center, filterList):
             if refFilterName is None:
                 continue
             try:
-                results = self.refObjLoader.loadSkyCircle(center,
-                                                          0.05*lsst.geom.degrees,
-                                                          refFilterName)
+                results = self.refObjLoader.loadSchema(refFilterName)
                 foundReferenceFilter = True
                 self._referenceFilter = refFilterName
                 break
@@ -377,7 +373,7 @@ def _determineFluxFields(self, center, filterList):
 
             if refFilterName is not None:
                 try:
-                    fluxField = getRefFluxField(results.refCat.schema, filterName=refFilterName)
+                    fluxField = getRefFluxField(results.schema, filterName=refFilterName)
                 except RuntimeError:
                     # This flux field isn't available.  Set to None
                     fluxField = None
diff --git a/tests/test_loadReferenceCatalog.py b/tests/test_loadReferenceCatalog.py
index dc171f345..2e9e4300c 100644
--- a/tests/test_loadReferenceCatalog.py
+++ b/tests/test_loadReferenceCatalog.py
@@ -63,6 +63,14 @@ def loadSkyCircle(self, ctrCoord, radius, filterName, **kwargs):
     def loadPixelBox(self, bbox, wcs, referenceFilter, **kwargs):
         return self.loadSkyCircle(None, None, referenceFilter)
 
+    def loadSchema(self, filterName):
+        refCat = self.make_synthetic_refcat(_synthCenter, _synthFlux)
+        fluxField = getRefFluxField(schema=refCat.schema, filterName=filterName)
+        return pipeBase.Struct(
+            schema=refCat.schema,
+            fluxField=fluxField
+        )
+
 
 class LoadReferenceCatalogTestCase(lsst.utils.tests.TestCase):
     @classmethod