FIX: IMAP archive fix and group list mailbox code unification (#10355)

* Fixed an issue I introduced in the last PR where I am just archiving everything regardless of whether it is actually archived in Discourse man_facepalming
* Refactor group list_mailboxes IMAP code to use providers, add specs, and add provider code to get the correct prodivder

spec/lib/imap/providers/detector_spec.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Imap::Providers::Detector do
+  it "returns the gmail provider if the gmail imap server is used" do
+    config = {
+      server: "imap.gmail.com",
+      port: 993,
+      ssl: true,
+      username: "test@gmail.com",
+      password: "testpassword1"
+    }
+    expect(described_class.init_with_detected_provider(config)).to be_a(Imap::Providers::Gmail)
+  end
+
+  it "returns the generic provider if we don't have a special provider defined" do
+    config = {
+      server: "imap.yo.com",
+      port: 993,
+      ssl: true,
+      username: "test@yo.com",
+      password: "testpassword1"
+    }
+    expect(described_class.init_with_detected_provider(config)).to be_a(Imap::Providers::Generic)
+  end
+end

spec/lib/imap/providers/gmail_spec.rb

@@ -0,0 +1,73 @@
+
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Imap::Providers::Gmail do
+  fab!(:username) { "test@generic.com" }
+  fab!(:password) { "test1!" }
+  fab!(:provider) do
+    described_class.new(
+      "imap.generic.com",
+      {
+        port: 993,
+        ssl: true,
+        username: username,
+        password: password
+      }
+    )
+  end
+
+  let(:imap_stub) { stub }
+  let(:x_gm_thrid) { Imap::Providers::Gmail::X_GM_THRID }
+  let(:x_gm_labels) { Imap::Providers::Gmail::X_GM_LABELS }
+  before do
+    described_class.any_instance.stubs(:imap).returns(imap_stub)
+  end
+
+  describe "#store" do
+    it "converts LABELS store to special X-GM-LABELS" do
+      Imap::Providers::Generic.any_instance.expects(:store).with(
+        63, x_gm_labels, ["\\Inbox"], ["\\Inbox", "test"]
+      )
+      provider.store(63, "LABELS", ["\\Inbox"], ["\\Inbox", "test"])
+    end
+  end
+
+  describe "#tag_to_label" do
+    it "converts important to special gmail label \\Important" do
+      expect(provider.tag_to_label("important")).to eq("\\Important")
+    end
+
+    it "converts starred to special gmail label \\Starred" do
+      expect(provider.tag_to_label("starred")).to eq("\\Starred")
+    end
+  end
+
+  describe "#archive" do
+    it "gets the thread ID for the UID, and removes the Inbox label from all UIDs in the thread" do
+      main_uid = 78
+      fake_thrid = '4398634986239754'
+      imap_stub.expects(:uid_fetch).with(main_uid, [x_gm_thrid]).returns(
+        [stub(attr: { x_gm_thrid => fake_thrid })]
+      )
+      imap_stub.expects(:uid_search).with("#{x_gm_thrid} #{fake_thrid}").returns([79, 80])
+      provider.expects(:emails).with([79, 80], ["UID", "LABELS"]).returns(
+        [
+          {
+            "UID" => 79,
+            "LABELS" => ["\\Inbox", "seen"]
+          },
+          {
+            "UID" => 80,
+            "LABELS" => ["\\Inbox", "seen"]
+          }
+        ]
+      )
+      provider.expects(:store).with(79, "LABELS", ["\\Inbox", "seen"], ["seen"])
+      provider.expects(:store).with(80, "LABELS", ["\\Inbox", "seen"], ["seen"])
+
+      provider.archive(main_uid)
+    end
+  end
+end