From 92c75c3e8c081c932cc9d5fe3cb39f22dbae7cf1 Mon Sep 17 00:00:00 2001
From: James Holderness <j4_james@hotmail.com>
Date: Thu, 9 Jan 2020 19:51:24 +0000
Subject: [PATCH] Add a state machine test to confirm the control characters
 are dispatched correctly.

---
 .../parser/ut_parser/OutputEngineTest.cpp     | 65 +++++++++++++++++++
 1 file changed, 65 insertions(+)

diff --git a/src/terminal/parser/ut_parser/OutputEngineTest.cpp b/src/terminal/parser/ut_parser/OutputEngineTest.cpp
index 794265428063..6b20f057907e 100644
--- a/src/terminal/parser/ut_parser/OutputEngineTest.cpp
+++ b/src/terminal/parser/ut_parser/OutputEngineTest.cpp
@@ -677,6 +677,10 @@ class StatefulDispatch final : public TermDispatch
         _cursorKeysMode{ false },
         _cursorBlinking{ true },
         _isOriginModeRelative{ false },
+        _warningBell{ false },
+        _carriageReturn{ false },
+        _forwardTab{ false },
+        _numTabs{ 0 },
         _isDECCOLMAllowed{ false },
         _windowWidth{ 80 },
         _options{ s_cMaxOptions, static_cast<DispatchTypes::GraphicsOptions>(s_uiGraphicsCleared) } // fill with cleared option
@@ -904,6 +908,25 @@ class StatefulDispatch final : public TermDispatch
         return true;
     }
 
+    bool WarningBell() noexcept override
+    {
+        _warningBell = true;
+        return true;
+    }
+
+    bool CarriageReturn() noexcept override
+    {
+        _carriageReturn = true;
+        return true;
+    }
+
+    bool ForwardTab(const size_t numTabs) noexcept override
+    {
+        _forwardTab = true;
+        _numTabs = numTabs;
+        return true;
+    }
+
     bool EnableDECCOLMSupport(const bool fEnabled) noexcept override
     {
         _isDECCOLMAllowed = fEnabled;
@@ -950,6 +973,10 @@ class StatefulDispatch final : public TermDispatch
     bool _cursorKeysMode;
     bool _cursorBlinking;
     bool _isOriginModeRelative;
+    bool _warningBell;
+    bool _carriageReturn;
+    bool _forwardTab;
+    size_t _numTabs;
     bool _isDECCOLMAllowed;
     size_t _windowWidth;
 
@@ -1783,4 +1810,42 @@ class StateMachineExternalTest final
 
         pDispatch->ClearState();
     }
+
+    TEST_METHOD(TestControlCharacters)
+    {
+        auto dispatch = std::make_unique<StatefulDispatch>();
+        auto pDispatch = dispatch.get();
+        auto engine = std::make_unique<OutputStateMachineEngine>(std::move(dispatch));
+        StateMachine mach(std::move(engine));
+
+        Log::Comment(L"BEL (Warning Bell) control character");
+        mach.ProcessCharacter(AsciiChars::BEL);
+
+        VERIFY_IS_TRUE(pDispatch->_warningBell);
+
+        pDispatch->ClearState();
+
+        Log::Comment(L"BS (Back Space) control character");
+        mach.ProcessCharacter(AsciiChars::BS);
+
+        VERIFY_IS_TRUE(pDispatch->_cursorBackward);
+        VERIFY_ARE_EQUAL(1u, pDispatch->_cursorDistance);
+
+        pDispatch->ClearState();
+
+        Log::Comment(L"CR (Carriage Return) control character");
+        mach.ProcessCharacter(AsciiChars::CR);
+
+        VERIFY_IS_TRUE(pDispatch->_carriageReturn);
+
+        pDispatch->ClearState();
+
+        Log::Comment(L"HT (Horizontal Tab) control character");
+        mach.ProcessCharacter(AsciiChars::TAB);
+
+        VERIFY_IS_TRUE(pDispatch->_forwardTab);
+        VERIFY_ARE_EQUAL(1u, pDispatch->_numTabs);
+
+        pDispatch->ClearState();
+    }
 };