Add ability to filter individual posts (#18945)

* Add database table for status-specific filters

* Add REST endpoints, entities and attributes

* Show status filters in /filters interface

* Perform server-side filtering for individual posts filters

* Fix filtering on context mismatch

* Refactor `toServerSideType` by moving it to its own module

* Move loupe and delete icons to their own module

* Add ability to filter individual posts from WebUI

* Replace keyword list by warnings (expired, context mismatch)

* Refactor server-side filtering code

* Add tests

4 files changed, 174 insertions, 0 deletions

diff --git a/spec/controllers/api/v1/filters/statuses_controller_spec.rb b/spec/controllers/api/v1/filters/statuses_controller_spec.rb
new file mode 100644
index 000000000..3b2399dd8
--- /dev/null
+++ b/spec/controllers/api/v1/filters/statuses_controller_spec.rb
@@ -0,0 +1,116 @@
+require 'rails_helper'
+
+RSpec.describe Api::V1::Filters::StatusesController, type: :controller do
+  render_views
+
+  let(:user)         { Fabricate(:user) }
+  let(:token)        { Fabricate(:accessible_access_token, resource_owner_id: user.id, scopes: scopes) }
+  let(:filter)       { Fabricate(:custom_filter, account: user.account) }
+  let(:other_user)   { Fabricate(:user) }
+  let(:other_filter) { Fabricate(:custom_filter, account: other_user.account) }
+
+  before do
+    allow(controller).to receive(:doorkeeper_token) { token }
+  end
+
+  describe 'GET #index' do
+    let(:scopes) { 'read:filters' }
+    let!(:status_filter) { Fabricate(:custom_filter_status, custom_filter: filter) }
+
+    it 'returns http success' do
+      get :index, params: { filter_id: filter.id }
+      expect(response).to have_http_status(200)
+    end
+
+    context "when trying to access another's user filters" do
+      it 'returns http not found' do
+        get :index, params: { filter_id: other_filter.id }
+        expect(response).to have_http_status(404)
+      end
+    end
+  end
+
+  describe 'POST #create' do
+    let(:scopes)    { 'write:filters' }
+    let(:filter_id) { filter.id }
+    let!(:status)   { Fabricate(:status) }
+
+    before do
+      post :create, params: { filter_id: filter_id, status_id: status.id }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'returns a status filter' do
+      json = body_as_json
+      expect(json[:status_id]).to eq status.id.to_s
+    end
+
+    it 'creates a status filter' do
+      filter = user.account.custom_filters.first
+      expect(filter).to_not be_nil
+      expect(filter.statuses.pluck(:status_id)).to eq [status.id]
+    end
+
+    context "when trying to add to another another's user filters" do
+      let(:filter_id) { other_filter.id }
+
+      it 'returns http not found' do
+        expect(response).to have_http_status(404)
+      end
+    end
+  end
+
+  describe 'GET #show' do
+    let(:scopes)  { 'read:filters' }
+    let!(:status_filter) { Fabricate(:custom_filter_status, custom_filter: filter) }
+
+    before do
+      get :show, params: { id: status_filter.id }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'returns expected data' do
+      json = body_as_json
+      expect(json[:status_id]).to eq status_filter.status_id.to_s
+    end
+
+    context "when trying to access another user's filter keyword" do
+      let(:status_filter) { Fabricate(:custom_filter_status, custom_filter: other_filter) }
+
+      it 'returns http not found' do
+        expect(response).to have_http_status(404)
+      end
+    end
+  end
+
+  describe 'DELETE #destroy' do
+    let(:scopes)  { 'write:filters' }
+    let(:status_filter) { Fabricate(:custom_filter_status, custom_filter: filter) }
+
+    before do
+      delete :destroy, params: { id: status_filter.id }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'removes the filter' do
+      expect { status_filter.reload }.to raise_error ActiveRecord::RecordNotFound
+    end
+
+    context "when trying to update another user's filter keyword" do
+      let(:status_filter) { Fabricate(:custom_filter_status, custom_filter: other_filter) }
+
+      it 'returns http not found' do
+        expect(response).to have_http_status(404)
+      end
+    end
+  end
+end
diff --git a/spec/controllers/api/v1/statuses_controller_spec.rb b/spec/controllers/api/v1/statuses_controller_spec.rb
index 4d104a198..24810a5d2 100644
--- a/spec/controllers/api/v1/statuses_controller_spec.rb
+++ b/spec/controllers/api/v1/statuses_controller_spec.rb
@@ -47,6 +47,33 @@ RSpec.describe Api::V1::StatusesController, type: :controller do
         end
       end
 
+      context 'when post is explicitly filtered' do
+        let(:status) { Fabricate(:status, text: 'hello world') }
+
+        before do
+          filter = user.account.custom_filters.create!(phrase: 'filter1', context: %w(home), action: :hide)
+          filter.statuses.create!(status_id: status.id)
+        end
+
+        it 'returns http success' do
+          get :show, params: { id: status.id }
+          expect(response).to have_http_status(200)
+        end
+
+        it 'returns filter information' do
+          get :show, params: { id: status.id }
+          json = body_as_json
+          expect(json[:filtered][0]).to include({
+            filter: a_hash_including({
+              id: user.account.custom_filters.first.id.to_s,
+              title: 'filter1',
+              filter_action: 'hide',
+            }),
+            status_matches: [status.id.to_s],
+          })
+        end
+      end
+
       context 'when reblog includes filtered terms' do
         let(:status) { Fabricate(:status, reblog: Fabricate(:status, text: 'this toot is about that banned word')) }
 
diff --git a/spec/fabricators/custom_filter_status_fabricator.rb b/spec/fabricators/custom_filter_status_fabricator.rb
new file mode 100644
index 000000000..d082b81c5
--- /dev/null
+++ b/spec/fabricators/custom_filter_status_fabricator.rb
@@ -0,0 +1,4 @@
+Fabricator(:custom_filter_status) do
+  custom_filter
+  status
+end
diff --git a/spec/presenters/status_relationships_presenter_spec.rb b/spec/presenters/status_relationships_presenter_spec.rb
index 5cd4929a6..eaab922fd 100644
--- a/spec/presenters/status_relationships_presenter_spec.rb
+++ b/spec/presenters/status_relationships_presenter_spec.rb
@@ -94,5 +94,32 @@ RSpec.describe StatusRelationshipsPresenter do
         expect(matched_filters[0].keyword_matches).to eq ['irrelevant']
       end
     end
+
+    context 'when post includes filtered individual statuses' do
+      let(:statuses) { [Fabricate(:status, text: 'hello world'), Fabricate(:status, reblog: Fabricate(:status, text: 'this toot is about an irrelevant word'))] }
+      let(:options) { {} }
+
+      before do
+        filter = Account.find(current_account_id).custom_filters.create!(phrase: 'filter1', context: %w(home), action: :hide)
+        filter.statuses.create!(status_id: statuses[0].id)
+        filter.statuses.create!(status_id: statuses[1].reblog_of_id)
+      end
+
+      it 'sets @filters_map to filter top-level status' do
+        matched_filters = presenter.filters_map[statuses[0].id]
+        expect(matched_filters.size).to eq 1
+
+        expect(matched_filters[0].filter.title).to eq 'filter1'
+        expect(matched_filters[0].status_matches).to eq [statuses[0].id]
+      end
+
+      it 'sets @filters_map to filter reblogged status' do
+        matched_filters = presenter.filters_map[statuses[1].reblog_of_id]
+        expect(matched_filters.size).to eq 1
+
+        expect(matched_filters[0].filter.title).to eq 'filter1'
+        expect(matched_filters[0].status_matches).to eq [statuses[1].reblog_of_id]
+      end
+    end
   end
 end