spec: add tests for LanguageSupport

This primarily consists of some spies added to ensure that the
LanguageSupport plugin is actually being called at the right time.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>

spec/unit/readerdictionary_spec.lua

@@ -24,7 +24,6 @@ describe("Readerdictionary module", function()
         readerui:onClose()
     end)
     it("should show quick lookup window", function()
-        local name = "screenshots/reader_dictionary.png"
         UIManager:quit()
         UIManager:show(readerui)
         rolling:onGotoPage(100)
@@ -36,6 +35,36 @@ describe("Readerdictionary module", function()
             ReaderUI.instance = readerui
         end)
         UIManager:run()
-        Screen:shot(name)
+        Screen:shot("screenshots/reader_dictionary.png")
+    end)
+    it("should attempt to deinflect (Japanese) word on lookup", function()
+        UIManager:quit()
+        UIManager:show(readerui)
+        rolling:onGotoPage(100)
+
+        local word = "喋っている"
+        local s = spy.on(readerui.languagesupport, "extraDictionaryFormCandidates")
+
+        -- We can't use onLookupWord because we need to check whether
+        -- extraDictionaryFormCandidates was called synchronously.
+        dictionary:stardictLookup(word)
+
+        assert.spy(s).was_called()
+        assert.spy(s).was_called_with(match.is_ref(readerui.languagesupport), word)
+        if readerui.languagesupport.plugins["japanese_support"] then
+            -- @todo This should probably check against a set or sorted list
+            --       of the candidates we'd expect.
+            assert.spy(s).was_returned_with(match.is_not_nil())
+        end
+        readerui.languagesupport.extraDictionaryFormCandidates:revert()
+
+        UIManager:scheduleIn(1, function()
+            UIManager:close(dictionary.dict_window)
+            UIManager:close(readerui)
+            -- We haven't torn it down yet
+            ReaderUI.instance = readerui
+        end)
+        UIManager:run()
+        Screen:shot("screenshots/reader_dictionary_japanese.png")
     end)
 end)