[28348] Coalesce values for contains filter

https://community.openproject.com/wp/28348

app/models/queries/operators/contains.rb

@@ -33,7 +33,7 @@ module Queries::Operators
     set_symbol '~'
 
     def self.sql_for_field(values, db_table, db_field)
-      "LOWER(#{db_table}.#{db_field}) LIKE " +
+      "COALESCE(LOWER(#{db_table}.#{db_field}), '') LIKE " +
         "'%#{connection.quote_string(values.first.to_s.downcase)}%'"
     end
   end

app/models/queries/operators/not_contains.rb

@@ -33,7 +33,7 @@ module Queries::Operators
     set_symbol '!~'
 
     def self.sql_for_field(values, db_table, db_field)
-      "LOWER(#{db_table}.#{db_field}) NOT LIKE " +
+      "COALESCE(LOWER(#{db_table}.#{db_field}), '') NOT LIKE " +
         "'%#{connection.quote_string(values.first.to_s.downcase)}%'"
     end
   end

spec/models/queries/work_packages/filter/custom_fields/contains_text_custom_field_filter_spec.rb

@@ -0,0 +1,97 @@
+#-- copyright
+# OpenProject is a project management system.
+# Copyright (C) 2012-2018 the OpenProject Foundation (OPF)
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2017 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# See docs/COPYRIGHT.rdoc for more details.
+#++
+
+require 'spec_helper'
+
+describe Queries::WorkPackages::Filter::CustomFieldFilter,
+         'with contains filter (Regression test #28348)',
+         type: :model do
+
+  let(:cf_accessor) { "cf_#{custom_field.id}" }
+  let(:query) { FactoryBot.build_stubbed(:query, project: project) }
+  let(:instance) do
+    described_class.create!(name: cf_accessor, operator: operator, values: %w(foo), context: query)
+  end
+
+  let(:project) do
+    FactoryBot.create :project,
+                      types: [type],
+                      work_package_custom_fields: [custom_field]
+  end
+  let(:custom_field) do
+    FactoryBot.create(:text_issue_custom_field, name: 'LongText')
+  end
+  let(:type) { FactoryBot.create(:type_standard, custom_fields: [custom_field]) }
+
+  let!(:wp_contains) do
+    FactoryBot.create :work_package,
+                      type: type,
+                      project: project,
+                      custom_values: { custom_field.id => 'foo' }
+  end
+  let!(:wp_not_contains) do
+    FactoryBot.create :work_package,
+                      type: type,
+                      project: project,
+                      custom_values: { custom_field.id => 'bar' }
+  end
+
+  let!(:wp_empty) do
+    FactoryBot.create :work_package,
+                      type: type,
+                      project: project,
+                      custom_values: { custom_field.id => '' }
+  end
+
+  let!(:wp_nil) do
+    FactoryBot.create :work_package,
+                      type: type,
+                      project: project,
+                      custom_values: { custom_field.id => nil }
+  end
+
+  subject { WorkPackage.where(instance.where) }
+
+  describe 'contains' do
+    let(:operator) { '~' }
+
+    it 'returns the one matching work package' do
+      is_expected
+        .to match_array [wp_contains]
+    end
+  end
+
+  describe 'not contains' do
+    let(:operator) { '!~' }
+
+    it 'returns the three non-matching work package' do
+      is_expected
+        .to match_array [wp_not_contains, wp_empty, wp_nil]
+    end
+  end
+end

spec_legacy/unit/query_spec.rb

@@ -191,7 +191,7 @@ describe Query, type: :model do
   it 'should operator contains' do
     query = Query.new(project: Project.find(1), name: '_')
     query.add_filter('subject', '~', ['uNable'])
-    assert query.statement.include?("LOWER(#{WorkPackage.table_name}.subject) LIKE '%unable%'")
+    assert query.statement.include?("COALESCE(LOWER(#{WorkPackage.table_name}.subject), '') LIKE '%unable%'")
     result = find_issues_with_query(query)
     assert result.empty?
     result.each { |issue| assert issue.subject.downcase.include?('unable') }
@@ -200,7 +200,7 @@ describe Query, type: :model do
   it 'should operator does not contains' do
     query = Query.new(project: Project.find(1), name: '_')
     query.add_filter('subject', '!~', ['uNable'])
-    assert query.statement.include?("LOWER(#{WorkPackage.table_name}.subject) NOT LIKE '%unable%'")
+    assert query.statement.include?("COALESCE(LOWER(#{WorkPackage.table_name}.subject), '') NOT LIKE '%unable%'")
     find_issues_with_query(query)
   end