Even cleaner solution

src/cascadia/TerminalCore/Terminal.cpp

@@ -431,7 +431,21 @@ void Terminal::Write(std::wstring_view stringView)
 {
     auto lock = LockForWriting();
 
+    auto& cursor = _buffer->GetCursor();
+    const til::point cursorPosBefore{ cursor.GetPosition() };
+
     _stateMachine->ProcessString(stringView);
+
+    const til::point cursorPosAfter{ cursor.GetPosition() };
+
+    // Firing the CursorPositionChanged event is very expensive so we try not to
+    // do that when the cursor does not need to be redrawn. We don't do this
+    // inside _AdjustCursorPosition, only once we're done writing the whole run
+    // of output.
+    if (cursorPosBefore != cursorPosAfter)
+    {
+        _NotifyTerminalCursorPositionChanged();
+    }
 }
 
 void Terminal::WritePastedText(std::wstring_view stringView)
@@ -989,12 +1003,6 @@ void Terminal::_WriteBuffer(const std::wstring_view& stringView)
     }
 
     cursor.EndDeferDrawing();
-
-    // Firing the CursorPositionChanged event is very expensive so we try not to
-    // do that when the cursor does not need to be redrawn. We don't do this
-    // inside _AdjustCursorPosition, only once we're done writing the whole run
-    // of output.
-    _NotifyTerminalCursorPositionChanged();
 }
 
 void Terminal::_AdjustCursorPosition(const COORD proposedPosition)

src/cascadia/TerminalCore/TerminalApi.cpp

@@ -92,10 +92,6 @@ try
     }
     _AdjustCursorPosition(cursorPos);
 
-    // Send an updated cursor position event. See GH#12210 for why this is done
-    // here instead of in _AdjustCursorPosition
-    _NotifyTerminalCursorPositionChanged();
-
     return true;
 }
 CATCH_RETURN_FALSE()

src/cascadia/UnitTests_TerminalCore/TerminalBufferTests.cpp

@@ -610,23 +610,24 @@ void TerminalBufferTests::TestCursorNotifications()
         callbackWasCalled = true;
         expectedCallbacks--;
         VERIFY_IS_GREATER_THAN_OR_EQUAL(expectedCallbacks, 0);
-        // VERIFY_IS_TRUE(expectedCallbacks >= 0);
     };
     term->_pfnCursorPositionChanged = cb;
 
+    // The exact number of callbacks here is fungible, if need be.
+
     expectedCallbacks = 1;
     callbackWasCalled = false;
     term->Write(L"Foo");
     VERIFY_ARE_EQUAL(0, expectedCallbacks);
     VERIFY_IS_TRUE(callbackWasCalled);
 
-    expectedCallbacks = 3; // one for foo, one for the newline, one for bar
+    expectedCallbacks = 1;
     callbackWasCalled = false;
     term->Write(L"Foo\r\nBar");
     VERIFY_ARE_EQUAL(0, expectedCallbacks);
     VERIFY_IS_TRUE(callbackWasCalled);
 
-    expectedCallbacks = 6;
+    expectedCallbacks = 2; // One for each Write
     callbackWasCalled = false;
     term->Write(L"Foo\r\nBar");
     term->Write(L"Foo\r\nBar");