More strictly adhere to nvdaControllerClient and Tolk parameters.

docs/wine-accessibility.md

@@ -23,7 +23,8 @@ nonactivating, and excluded from ordinary window switching. Therefore applicatio
 `nvdaControllerClient32.dll`, `nvdaControllerClient64.dll`, and `Tolk.dll`; no DLL override is
 required.
 
-Plain speech, braille, cancel, and process ID calls are implemented. Speaking-state queries return
+Plain speech queues like NVDA Controller output; Tolk's interrupt flag uses the separate cancel call
+before speaking. Braille, cancel, and process ID calls are also implemented. Speaking-state queries return
 `ERROR_CALL_NOT_IMPLEMENTED`, because Cthulhu's current speech backend does not expose an accurate
 answer. SSML is validated by Cthulhu and currently fails with `ERROR_NOT_SUPPORTED`. This is
 intentional: accepting SSML while dropping mark callbacks or reporting completion too early would

tests/test_wine_access_controller_contract.py

@@ -0,0 +1,24 @@
+import re
+import unittest
+from pathlib import Path
+
+
+class WineAccessControllerContractTests(unittest.TestCase):
+    def test_legacy_speak_text_queues_without_cancelling_current_speech(self):
+        sourcePath = Path(__file__).resolve().parents[1] / "wine-access" / "main.cpp"
+        source = sourcePath.read_text(encoding="utf-8")
+        match = re.search(
+            r'extern "C" error_status_t __stdcall speakText\(.*?\n\}',
+            source,
+            re.DOTALL,
+        )
+
+        self.assertIsNotNone(match)
+        self.assertIn(
+            'g_variant_new("(sb)", utf8.c_str(), FALSE)',
+            match.group(0),
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

wine-access/main.cpp

@@ -440,7 +440,8 @@ extern "C" error_status_t __stdcall testIfRunning(void) {
 }
 extern "C" error_status_t __stdcall speakText(const wchar_t *text) {
   const std::string utf8 = to_utf8(text);
-  return call_boolean("SpeakText", g_variant_new("(sb)", utf8.c_str(), TRUE));
+  // Tolk calls cancelSpeech separately when its interrupt argument is true.
+  return call_boolean("SpeakText", g_variant_new("(sb)", utf8.c_str(), FALSE));
 }
 extern "C" error_status_t __stdcall cancelSpeech(void) {
   return call_boolean("CancelSpeech", nullptr);