Fix display name for cumulative count without column (#31271)

src/metabase/lib/aggregation.cljc

@@ -66,20 +66,34 @@
   [query stage-number [_tag _opts index] style]
   (lib.metadata.calculation/display-name query stage-number (resolve-aggregation query stage-number index) style))
 
-(defmethod lib.metadata.calculation/display-name-method :count
-  [query stage-number [_count _opts x] style]
+(lib.hierarchy/derive ::count-aggregation ::aggregation)
+
+;;; count and cumulative count can both be used either with no args (count of rows) or with one arg (count of X, which
+;;; I think means count where X is not NULL or something like that. Basically `count(x)` in SQL)
+(doseq [tag [:count
+             :cum-count]]
+  (lib.hierarchy/derive tag ::count-aggregation))
+
+(defmethod lib.metadata.calculation/display-name-method ::count-aggregation
+  [query stage-number [tag _opts x] style]
   ;; x is optional.
   (if x
-    (i18n/tru "Count of {0}" (lib.metadata.calculation/display-name query stage-number x style))
-    (i18n/tru "Count")))
+    (let [x-display-name (lib.metadata.calculation/display-name query stage-number x style)]
+      (case tag
+        :count     (i18n/tru "Count of {0}" x-display-name)
+        :cum-count (i18n/tru "Cumulative count of {0}" x-display-name)))
+    (case tag
+      :count     (i18n/tru "Count")
+      :cum-count (i18n/tru "Cumulative count"))))
 
 (defmethod lib.metadata.calculation/column-name-method :count
-  [query stage-number [_count _opts x]]
-  (if x
-    (str "count_" (lib.metadata.calculation/column-name query stage-number x))
-    "count"))
-
-(lib.hierarchy/derive :count ::aggregation)
+  [query stage-number [tag _opts x]]
+  (let [prefix (case tag
+                 :count     "count"
+                 :cum-count "cum_count")]
+    (if x
+      (str prefix \_ (lib.metadata.calculation/column-name query stage-number x))
+      prefix)))
 
 (defmethod lib.metadata.calculation/display-name-method :case
   [_query _stage-number _case _style]
@@ -89,10 +103,11 @@
   [_query _stage-number _case]
   "case")
 
+;;; TODO - Should `:case` derive from `::aggregation` as well???
+
 (lib.hierarchy/derive ::unary-aggregation ::aggregation)
 
 (doseq [tag [:avg
-             :cum-count
              :cum-sum
              :distinct
              :max
@@ -109,7 +124,6 @@
     (str
      (case tag
        :avg       "avg_"
-       :cum-count "cum_count_"
        :cum-sum   "cum_sum_"
        :distinct  "distinct_"
        :max       "max_"
@@ -125,7 +139,6 @@
   (let [arg (lib.metadata.calculation/display-name query stage-number arg style)]
     (case tag
       :avg       (i18n/tru "Average of {0}"            arg)
-      :cum-count (i18n/tru "Cumulative count of {0}"   arg)
       :cum-sum   (i18n/tru "Cumulative sum of {0}"     arg)
       :distinct  (i18n/tru "Distinct values of {0}"    arg)
       :max       (i18n/tru "Max of {0}"                arg)

src/metabase/lib/core.cljc

@@ -73,7 +73,9 @@
    stddev
    sum
    sum-where
-   var]
+   var
+   cum-count
+   cum-sum]
   [lib.binning
    available-binning-strategies
    binning