[fix #2905] fix DATE_TRUNC usage

DATE_TRUNC is played on the db where the timestamp are stored in utc.
So if a user search for 12/12/2012 in Paris timezone and that we truncate it should do something similar to :

SELECT DATE_TRUNC('day', foo.timezone) from (SELECT timestamp '2012-12-12 00:00:00' AT TIME ZONE 'Europe/Paris') as foo;
=> 2012-12-11

To avoid such pb, I suggest avoiding DATE_TRUNC when exact results are needed

app/models/procedure_presentation.rb

@@ -111,8 +111,12 @@ class ProcedurePresentation < ApplicationRecord
       column = sanitized_column(filter)
       case table
       when 'self'
-        date = filter['value'].to_date rescue nil
-        dossiers.where("DATE_TRUNC('day', #{column}) = ?", date)
+        date = Time.zone.parse(filter['value'])
+        if date.present?
+          dossiers.where("#{column} BETWEEN ? AND ?", date, date + 1.day)
+        else
+          []
+        end
       when 'type_de_champ', 'type_de_champ_private'
         relation = table == 'type_de_champ' ? :champs : :champs_private
         dossiers

spec/controllers/stats_controller_spec.rb

@@ -72,9 +72,9 @@ describe StatsController, type: :controller do
 
       it do
         expect(subject).to eq({
-          2.months.ago.beginning_of_month => 2,
-          1.month.ago.beginning_of_month => 4,
-          1.hour.ago.beginning_of_month => 5
+          Time.utc(2016, 8, 1) => 2,
+          Time.utc(2016, 9, 1) => 4,
+          Time.utc(2016, 10, 1) => 5
         })
       end
     end
@@ -86,8 +86,8 @@ describe StatsController, type: :controller do
 
       it do
         expect(subject).to eq({
-          2.months.ago.beginning_of_month => 2,
-          1.month.ago.beginning_of_month => 4
+          Time.utc(2016, 8, 1) => 2,
+          Time.utc(2016, 9, 1) => 4
         })
       end
     end

spec/models/procedure_presentation_spec.rb

@@ -404,6 +404,11 @@ describe ProcedurePresentation do
 
         it { is_expected.to contain_exactly(kept_dossier.id) }
       end
+
+      context 'for a malformed date' do
+        let(:filter) { [{ 'table' => 'self', 'column' => 'updated_at', 'value' => 'malformed date' }] }
+        it { is_expected.to match([]) }
+      end
     end
 
     context 'for type_de_champ table' do