diff --git a/test/test_plugin_manager.rb b/test/test_plugin_manager.rb
index 22ad617f..c625c3a8 100644
--- a/test/test_plugin_manager.rb
+++ b/test/test_plugin_manager.rb
@@ -8,29 +8,146 @@ class TestPluginManager < JekyllUnitTest
     FileUtils.mv "Gemfile.old", "Gemfile"
   end
 
-  def test_requiring_from_bundler
-    with_env("JEKYLL_NO_BUNDLER_REQUIRE", nil) do
-      assert Jekyll::PluginManager.require_from_bundler,
-             "require_from_bundler should return true."
-      assert ENV["JEKYLL_NO_BUNDLER_REQUIRE"], "Gemfile plugins were not required."
-    end
-  end
-
-  def test_blocking_requiring_from_bundler
-    with_env("JEKYLL_NO_BUNDLER_REQUIRE", "true") do
-      assert_equal false, Jekyll::PluginManager.require_from_bundler,
-                   "Gemfile plugins were required but shouldn't have been"
-      assert ENV["JEKYLL_NO_BUNDLER_REQUIRE"]
-    end
-  end
-
-  def test_no_gemfile
-    with_env("JEKYLL_NO_BUNDLER_REQUIRE", nil) do
-      with_no_gemfile do
-        assert_equal false, Jekyll::PluginManager.require_from_bundler,
-                     "Gemfile plugins were required but shouldn't have been"
-        assert_nil ENV["JEKYLL_NO_BUNDLER_REQUIRE"]
+  context "JEKYLL_NO_BUNDLER_REQUIRE set to `nil`" do
+    should "require from bundler" do
+      with_env("JEKYLL_NO_BUNDLER_REQUIRE", nil) do
+        assert Jekyll::PluginManager.require_from_bundler,
+               "require_from_bundler should return true."
+        assert ENV["JEKYLL_NO_BUNDLER_REQUIRE"], "Gemfile plugins were not required."
       end
     end
   end
+
+  context "JEKYLL_NO_BUNDLER_REQUIRE set to `true`" do
+    should "not require from bundler" do
+      with_env("JEKYLL_NO_BUNDLER_REQUIRE", "true") do
+        refute Jekyll::PluginManager.require_from_bundler,
+                     "Gemfile plugins were required but shouldn't have been"
+        assert ENV["JEKYLL_NO_BUNDLER_REQUIRE"]
+      end
+    end
+  end
+
+  context "JEKYLL_NO_BUNDLER_REQUIRE set to `nil` and no Gemfile present" do
+    should "not require from bundler" do
+      with_env("JEKYLL_NO_BUNDLER_REQUIRE", nil) do
+        with_no_gemfile do
+          refute Jekyll::PluginManager.require_from_bundler,
+                       "Gemfile plugins were required but shouldn't have been"
+          assert_nil ENV["JEKYLL_NO_BUNDLER_REQUIRE"]
+        end
+      end
+    end
+  end
+
+  context "require gems" do
+    should "invoke `require_with_graceful_fail`" do
+      gems = %w(jemojii foobar)
+
+      expect(Jekyll::External).to(
+        receive(:require_with_graceful_fail).with(gems).and_return(nil)
+      )
+      site = double(:gems => gems)
+      plugin_manager = PluginManager.new(site)
+
+      allow(plugin_manager).to receive(:plugin_allowed?).with("foobar").and_return(true)
+      allow(plugin_manager).to receive(:plugin_allowed?).with("jemojii").and_return(true)
+
+      plugin_manager.require_gems
+    end
+  end
+
+  context "site is not marked as safe" do
+    should "allow all plugins" do
+      site = double(:safe => false)
+      plugin_manager = PluginManager.new(site)
+
+      assert plugin_manager.plugin_allowed?("foobar")
+    end
+
+    should "require plugin files" do
+      site = double({ :safe          => false,
+                      :config        => { "plugins_dir" => "_plugins" },
+                      :in_source_dir => "/tmp/" })
+      plugin_manager = PluginManager.new(site)
+
+      expect(Jekyll::External).to receive(:require_with_graceful_fail)
+      plugin_manager.require_plugin_files
+    end
+  end
+
+  context "site is marked as safe" do
+    should "allow plugins if they are whitelisted" do
+      site = double({ :safe => true, :config => { "whitelist" => ["jemoji"] } })
+      plugin_manager = PluginManager.new(site)
+
+      assert plugin_manager.plugin_allowed?("jemoji")
+      assert !plugin_manager.plugin_allowed?("not_allowed_plugin")
+    end
+
+    should "not require plugin files" do
+      site = double({ :safe => true })
+      plugin_manager = PluginManager.new(site)
+
+      expect(Jekyll::External).to_not receive(:require_with_graceful_fail)
+      plugin_manager.require_plugin_files
+    end
+  end
+
+  context "plugins_dir is set to the default" do
+    should "call site's in_source_dir" do
+      site = double({
+        :config        => {
+          "plugins_dir" => Jekyll::Configuration::DEFAULTS["plugins_dir"]
+        },
+        :in_source_dir => "/tmp/"
+      })
+      plugin_manager = PluginManager.new(site)
+
+      expect(site).to receive(:in_source_dir).with("_plugins")
+      plugin_manager.plugins_path
+    end
+  end
+
+  context "plugins_dir is set to a different dir" do
+    should "expand plugin path" do
+      site = double({ :config => { "plugins_dir" => "some_other_plugins_path" } })
+      plugin_manager = PluginManager.new(site)
+
+      expect(File).to receive(:expand_path).with("some_other_plugins_path")
+      plugin_manager.plugins_path
+    end
+  end
+
+  context "`paginate` config is activated" do
+    should "print deprecation warning if jekyll-paginate is not present" do
+      site = double({ :config => { "paginate" => true } })
+      plugin_manager = PluginManager.new(site)
+
+      expect(Jekyll::Deprecator).to(
+        receive(:deprecation_message).with(%r!jekyll-paginate!)
+      )
+      plugin_manager.deprecation_checks
+    end
+
+    should "print no deprecation warning if jekyll-paginate is present" do
+      site = double({
+        :config => { "paginate" => true, "gems" => ["jekyll-paginate"] }
+      })
+      plugin_manager = PluginManager.new(site)
+
+      expect(Jekyll::Deprecator).to_not receive(:deprecation_message)
+      plugin_manager.deprecation_checks
+    end
+  end
+
+  should "conscientious require" do
+    site = double
+    plugin_manager = PluginManager.new(site)
+
+    expect(plugin_manager).to(
+      receive_messages([:require_plugin_files, :require_gems, :deprecation_checks])
+    )
+    plugin_manager.conscientious_require
+  end
 end