[FIX] web: prevent crash in graph when grouping/aggregating on m2o

We recently added the possibility of aggregating the graph view on a
many2one field (with count distinct operator).  This is useful, but then
a rare situation could happen: the view could be grouped by the same
field.

In that case, there is a name clash in the read_group, and the result
will be that the [id, nameget] of a m2o field will be used as an
aggregate.

The readgroup method should be improved (its API is a mess), but
meanwhile, we have a solution for this issue: if we group by a m2o, then
it is guaranteed that each group has an aggregate value of 1 for the
same field.

1 files changed, 12 insertions, 1 deletions

diff --git a/addons/web/static/src/js/views/graph/graph_model.js b/addons/web/static/src/js/views/graph/graph_model.js
index f73a40d6b47..2ffbd4c4cf8 100644
--- a/addons/web/static/src/js/views/graph/graph_model.js
+++ b/addons/web/static/src/js/views/graph/graph_model.js
@@ -165,8 +165,19 @@ return AbstractModel.extend({
             labels = _.map(this.chart.groupedBy, function (field) {
                 return self._sanitizeValue(data_pt[field], field);
             });
+            var value = is_count ? data_pt.__count || data_pt[this.chart.groupedBy[0]+'_count'] : data_pt[this.chart.measure];
+            if (value instanceof Array) {
+                // when a many2one field is used as a measure AND as a grouped
+                // field, bad things happen.  The server will only return the
+                // grouped value and will not aggregate it.  Since there is a
+                // nameclash, we are then in the situation where this value is
+                // an array.  Fortunately, if we group by a field, then we can
+                // say for certain that the group contains exactly one distinct
+                // value for that field.
+                value = 1;
+            }
             this.chart.data.push({
-                value: is_count ? data_pt.__count || data_pt[this.chart.groupedBy[0]+'_count'] : data_pt[this.chart.measure],
+                value: value,
                 labels: labels
             });
         }