From b3e55b753b9661fe9094a70e5b3bf5aa450a3663 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sb@m-labs.hk>
Date: Tue, 24 May 2016 08:58:34 -0500
Subject: [PATCH] environment,dashboard: generalize multiple defaults, fix HDF5
 argument load

---
 artiq/dashboard/experiments.py | 7 ++++++-
 artiq/gui/entries.py           | 4 +++-
 artiq/language/environment.py  | 4 ++++
 artiq/language/scan.py         | 2 +-
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/artiq/dashboard/experiments.py b/artiq/dashboard/experiments.py
index c5401f213..61d27bce2 100644
--- a/artiq/dashboard/experiments.py
+++ b/artiq/dashboard/experiments.py
@@ -331,7 +331,12 @@ class _ExperimentDock(QtWidgets.QMdiSubWindow):
                          self.expurl, exc_info=True)
             return
         for k, v in overrides.items():
-            arginfo[k][0]["default"] = v
+            # Some values (e.g. scans) may have multiple defaults in a list
+            if ("default" in arginfo[k][0]
+                    and isinstance(arginfo[k][0]["default"], list)):
+                arginfo[k][0]["default"].insert(0, v)
+            else:
+                arginfo[k][0]["default"] = v
         self.manager.initialize_submission_arguments(self.expurl, arginfo)
 
         self.argeditor.deleteLater()
diff --git a/artiq/gui/entries.py b/artiq/gui/entries.py
index 900023ee4..8dc0a9ea3 100644
--- a/artiq/gui/entries.py
+++ b/artiq/gui/entries.py
@@ -274,8 +274,10 @@ class _ScanEntry(LayoutWidget):
         }
         if "default" in procdesc:
             defaults = procdesc["default"]
+            if not isinstance(defaults, list):
+                defaults = [defaults]
             state["selected"] = defaults[0]["ty"]
-            for default in defaults:
+            for default in reversed(defaults):
                 ty = default["ty"]
                 if ty == "NoScan":
                     state[ty]["value"] = default["value"]
diff --git a/artiq/language/environment.py b/artiq/language/environment.py
index 53b3fa38f..62dae4803 100644
--- a/artiq/language/environment.py
+++ b/artiq/language/environment.py
@@ -23,6 +23,10 @@ class DefaultMissing(Exception):
 
 class _SimpleArgProcessor:
     def __init__(self, default=NoDefault):
+        # If default is a list, it means multiple defaults are specified, with
+        # decreasing priority.
+        if isinstance(default, list):
+            raise NotImplementedError
         if default is not NoDefault:
             self.default_value = default
 
diff --git a/artiq/language/scan.py b/artiq/language/scan.py
index c7f6c6a9b..f674d0433 100644
--- a/artiq/language/scan.py
+++ b/artiq/language/scan.py
@@ -166,7 +166,7 @@ class Scannable:
         if global_step is None:
             global_step = scale/10.0
         if default is not NoDefault:
-            if not isinstance(default, (tuple, list)):
+            if not isinstance(default, list):
                 default = [default]
             self.default_values = default
         self.unit = unit