Correctly parse fk-> field references + Ensure time is 1st dimension

resources/automagic_dashboards/metric/GenericMetric.yaml

@@ -145,8 +145,8 @@ cards:
       title: "[[this]] per [[GenericCategorySmall]] over time"
       metrics: this
       dimensions:
-        - GenericCategorySmall
         - Timestamp
+        - GenericCategorySmall
       visualization:
         area:
           stackable.stack_type: stacked

src/metabase/automagic_dashboards/filters.clj

@@ -12,7 +12,7 @@
   [(s/one (s/constrained su/KeywordOrString
                          (comp #{:field-id :fk-> :field-literal} qp.util/normalize-token))
           "head")
-   (s/cond-pre s/Int su/KeywordOrString)])
+   (s/cond-pre s/Int su/KeywordOrString (s/recursive #'FieldReference))])
 
 (def ^:private ^{:arglists '([form])} field-reference?
   "Is given form an MBQL field reference?"
@@ -31,7 +31,9 @@
 
 (defmethod field-reference->id :fk->
   [[_ _ id]]
-  id)
+  (if (sequential? id)
+    (field-reference->id id)
+    id))
 
 (defmethod field-reference->id :field-literal
   [[_ name _]]
@@ -42,7 +44,9 @@
    form."
   [form]
   (->> form
-       (tree-seq (some-fn sequential? map?) identity)
+       (tree-seq (every-pred (some-fn sequential? map?)
+                             (complement field-reference?))
+                 identity)
        (filter field-reference?)))
 
 (def ^{:arglists '([field])} periodic-datetime?

src/metabase/query_processor/middleware/binning.clj

@@ -73,7 +73,7 @@
 (s/defn ^:private resolve-default-strategy :- [(s/one (s/enum :bin-width :num-bins) "strategy")
                                                (s/one {:bin-width s/Num, :num-bins su/IntGreaterThanZero} "opts")]
   "Determine the approprate strategy & options to use when `:default` strategy was specified."
-  [metadata :- {:special_type su/FieldType, s/Any s/Any}, min-value :- s/Num, max-value :- s/Num]
+  [metadata :- {:special_type (s/maybe su/FieldType), s/Any s/Any}, min-value :- s/Num, max-value :- s/Num]
   (if (isa? (:special_type metadata) :type/Coordinate)
     (let [bin-width (public-settings/breakout-bin-width)]
       [:bin-width