619353d17795a1211e21aac1b64b4aba8e67bdd1
angie
  Wed Aug 2 09:14:15 2017 -0700
Added missing NULL check to catch failure when changing to a new group.  refs #19930, #19920 note-7

diff --git src/hg/hgTablesTest/hgTablesTest.c src/hg/hgTablesTest/hgTablesTest.c
index 1c97772..a797959 100644
--- src/hg/hgTablesTest/hgTablesTest.c
+++ src/hg/hgTablesTest/hgTablesTest.c
@@ -805,30 +805,32 @@
 /* Clean up. */
 htmlPageFree(&trackPage);
 }
 
 void testOneGroup(struct htmlPage *dbPage, char *org, char *db, char *group, 
 	int maxTracks)
 /* Test a little something on up to maxTracks in one group */
 {
 struct htmlPage *groupPage = quickSubmit(dbPage, org, db, group, NULL, NULL,
 	"selectGroup", hgtaGroup, group);
 struct htmlForm *mainForm;
 struct htmlFormVar *trackVar;
 struct slName *track;
 int trackIx;
 
+if (groupPage == NULL)
+    errAbort("Error when changing group to %s", group);
 if ((mainForm = htmlFormGet(groupPage, "mainForm")) == NULL)
     errAbort("Couldn't get main form on groupPage");
 if ((trackVar = htmlFormVarGet(mainForm, hgtaTrack)) == NULL)
     errAbort("Can't find track var");
 
 // put the tracks in random order:
 if (!noShuffle)
     shuffleList(&trackVar->values);
 
 for (track = trackVar->values, trackIx = 0; 
 	track != NULL && trackIx < maxTracks; 
 	track = track->next)
     {
     if (clTrack && !sameString(track->name, clTrack))
 	continue;