FIX: Reports did not respect user locale (#30524)

Our bulk report endpoint uses `hijack`, which does not
use the current user's locale via the `with_resolved_locale`
method in `ApplicationController`. This is happening because
we are doing `around_action` to set the locale, then calling
the code in the block inside the action directly when we use
`hijack`.

We can fix this by capturing `I18n.locale` when starting the
hijack then using `I18n.with_locale` when evaluating the
block inside `hijack`, this way the translations will always
use the correct locale based on the current user.

lib/hijack.rb

@@ -13,6 +13,10 @@ module Hijack
       request.env["discourse.request_tracker.skip"] = true
       request_tracker = request.env["discourse.request_tracker"]
 
+      # need this because we can't call with_resolved_locale with around_action
+      # when we are evaluating the block
+      resolved_locale = I18n.locale
+
       # in the past unicorn would recycle env, this is not longer the case
       env = request.env
 
@@ -61,7 +65,7 @@ module Hijack
 
           view_start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
           begin
-            instance.instance_eval(&blk)
+            I18n.with_locale(resolved_locale) { instance.instance_eval(&blk) }
           rescue => e
             # TODO we need to reuse our exception handling in ApplicationController
             Discourse.warn_exception(

spec/lib/hijack_spec.rb

@@ -5,6 +5,7 @@ RSpec.describe Hijack do
     attr_reader :io
 
     include Hijack
+    include CurrentUser
 
     def initialize(env = {})
       @io = StringIO.new
@@ -232,4 +233,34 @@ RSpec.describe Hijack do
 
     expect(tester.response.status).to eq(503)
   end
+
+  context "when there is a current user" do
+    fab!(:test_current_user) { Fabricate(:user) }
+
+    it "captures the current user" do
+      test_user_id = nil
+
+      tester =
+        Hijack::Tester.new(Auth::DefaultCurrentUserProvider::CURRENT_USER_KEY => test_current_user)
+
+      tester.hijack_test { test_user_id = current_user.id }
+
+      expect(test_user_id).to eq(test_current_user.id)
+    end
+
+    it "uses the current user's locale for translations" do
+      SiteSetting.allow_user_locale = true
+      test_current_user.update!(locale: "es")
+      test_translation = nil
+
+      tester =
+        Hijack::Tester.new(Auth::DefaultCurrentUserProvider::CURRENT_USER_KEY => test_current_user)
+
+      # Simulates the around_action that sets the locale in ApplicationController, since this is
+      # not a request spec.
+      tester.with_resolved_locale { tester.hijack_test { test_translation = I18n.t("topics") } }
+
+      expect(test_translation).to eq(I18n.t("topics", locale: "es"))
+    end
+  end
 end

spec/requests/admin/reports_controller_spec.rb

@@ -56,8 +56,9 @@ RSpec.describe Admin::ReportsController do
       before { sign_in(admin) }
 
       context "with valid params" do
+        fab!(:topic)
+
         it "renders the reports as JSON" do
-          Fabricate(:topic)
           get "/admin/reports/bulk.json",
               params: {
                 reports: {
@@ -73,6 +74,30 @@ RSpec.describe Admin::ReportsController do
           expect(response.status).to eq(200)
           expect(response.parsed_body["reports"].count).to eq(2)
         end
+
+        it "uses the user's locale for report names and descriptions" do
+          SiteSetting.allow_user_locale = true
+          admin.update!(locale: "es")
+          get "/admin/reports/bulk.json",
+              params: {
+                reports: {
+                  topics: {
+                    limit: 10,
+                  },
+                  likes: {
+                    limit: 10,
+                  },
+                },
+              }
+
+          expect(response.status).to eq(200)
+          expect(response.parsed_body["reports"].first["title"]).to eq(
+            I18n.t("reports.topics.title", locale: "es"),
+          )
+          expect(response.parsed_body["reports"].first["description"]).to eq(
+            I18n.t("reports.topics.description", locale: "es"),
+          )
+        end
       end
 
       context "with invalid params" do