Merge pull request #3016 from pipecat-ai/mb/revert-concat-aggregated-text

Revert "Merge pull request #3004 from pipecat-ai/mb/improve-concat-ag…

CHANGELOG.md

@@ -90,10 +90,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Updated `simli-ai` to 0.1.25.
 
-- Improved `concatenate_aggregated_text()` to one word outputs from OpenAI
-  Realtime and Gemini Live. Text fragments are now correctly concatenated
-  without spaces when these patterns are detected.
-
 - `STTMuteFilter` no longer sends `STTMuteFrame` to the STT service. The filter
   now blocks frames locally without instructing the STT service to stop
   processing audio. This prevents inactivity-related errors (such as 409 errors

src/pipecat/utils/string.py

@@ -218,43 +218,15 @@ def concatenate_aggregated_text(text_parts: List[str]) -> str:
     has_leading_spaces = any(part and part[0] == " " for part in text_parts[1:])
     has_trailing_spaces = any(part and part[-1] == " " for part in text_parts[:-1])
 
-    # Check for trailing non-space whitespace (e.g., \n, \r, \t) which indicates
+    # If there are embedded spaces in the fragments, use direct concatenation
-    # syllable-by-syllable output with line breaks.
+    contains_spacing_between_fragments = has_leading_spaces or has_trailing_spaces
-    # Example: Gemini Live: ["Met", "amo", "rph", "osi", "s.\n"]
-    has_trailing_whitespace = any(
-        part and part[-1] != " " and part[-1].isspace() for part in text_parts
-    )
 
-    # Check if we have punctuation-only fragments, which indicates syllable-by-syllable
+    # Apply corresponding joining method
-    # output where punctuation arrives as a separate fragment.
+    if contains_spacing_between_fragments:
-    # Example: OpenAI Realtime single word: ["Met", "am", "orph", "osis", "."]
+        # Fragments already have spacing - just concatenate
-    punctuation_chars = ".,!?;:—-'\"…"
-    has_punctuation_only = any(
-        part and len(part.strip()) == 0 or all(c in punctuation_chars for c in part)
-        for part in text_parts
-    )
-
-    # If there are embedded spaces or other whitespace in the fragments, use direct concatenation
-    contains_spacing_between_fragments = (
-        has_leading_spaces or has_trailing_spaces or has_trailing_whitespace
-    )
-
-    # Apply corresponding joining method based on detected spacing patterns:
-
-    if has_punctuation_only and not contains_spacing_between_fragments:
-        # Syllable-by-syllable output with standalone punctuation fragment. Examples:
-        # - OpenAI Realtime: ["Met", "am", "orph", "osis", "."] → "Metamorphosis."
-        result = "".join(text_parts)
-    elif contains_spacing_between_fragments:
-        # Fragments already have embedded spacing or trailing whitespace - concatenate directly. Examples:
-        # - OpenAI Realtime: ['Hey', ' there', '!', ' Great', ' to', ' meet', ' you', '!']
-        # - Gemini Live (spaces): ['Hel', 'lo.', ' Wo', 'u', 'ld ', 'you', ' li', 'ke ', 'to ', 'he', 'ar a joke?\n']
-        # - Gemini Live (newline): ["Met", "amo", "rph", "osi", "s.\n"] → "Metamorphosis."
-        # - Sentence level TTS services: ['Hello!', ' How can I assist you today?']
         result = "".join(text_parts)
     else:
-        # Word-by-word fragments without spacing - join with spaces. Examples:
+        # Word-by-word fragments - join with spaces
-        # - Word level TTS services: ["Hello", "there.", "How", "are", "you?"] → "Hello there. How are you?"
         result = " ".join(text_parts)
 
     # Clean up any excessive whitespace

tests/test_transcript_processor.py

@@ -479,103 +479,3 @@ class TestUserTranscriptProcessor(unittest.IsolatedAsyncioTestCase):
         self.assertEqual(message.role, "assistant")
         # Should be properly joined without extra spaces
         self.assertEqual(message.content, "Hello there! How's it going?")
-
-    async def test_openai_realtime_syllable_fragments(self):
-        """Test OpenAI Realtime syllable-by-syllable output with standalone punctuation
-
-        OpenAI Realtime can output single words as syllable fragments with punctuation
-        as a separate fragment. Example: ["Met", "am", "orph", "osis", "."]
-        This should be concatenated without spaces to form "Metamorphosis."
-        """
-        processor = AssistantTranscriptProcessor()
-
-        received_updates = []
-
-        @processor.event_handler("on_transcript_update")
-        async def handle_update(proc, frame: TranscriptionUpdateFrame):
-            received_updates.append(frame)
-
-        # Simulate OpenAI Realtime syllable-by-syllable output
-        frames_to_send = [
-            BotStartedSpeakingFrame(),
-            SleepFrame(),
-            TTSTextFrame(text="Met"),
-            TTSTextFrame(text="am"),
-            TTSTextFrame(text="orph"),
-            TTSTextFrame(text="osis"),
-            TTSTextFrame(text="."),  # Standalone punctuation fragment
-            BotStoppedSpeakingFrame(),
-        ]
-
-        expected_down_frames = [
-            BotStartedSpeakingFrame,
-            BotStoppedSpeakingFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TranscriptionUpdateFrame,
-        ]
-
-        await run_test(
-            processor,
-            frames_to_send=frames_to_send,
-            expected_down_frames=expected_down_frames,
-        )
-
-        # Verify syllables are concatenated without spaces
-        self.assertEqual(len(received_updates), 1)
-        message = received_updates[0].messages[0]
-        self.assertEqual(message.role, "assistant")
-        self.assertEqual(message.content, "Metamorphosis.")
-
-    async def test_gemini_live_syllable_fragments_with_newline(self):
-        """Test Gemini Live syllable-by-syllable output with trailing newline
-
-        Gemini Live can output syllable fragments where the last fragment contains
-        trailing whitespace like newlines. Example: ["Met", "amo", "rph", "osi", "s.\\n"]
-        This should be concatenated without spaces to form "Metamorphosis."
-        """
-        processor = AssistantTranscriptProcessor()
-
-        received_updates = []
-
-        @processor.event_handler("on_transcript_update")
-        async def handle_update(proc, frame: TranscriptionUpdateFrame):
-            received_updates.append(frame)
-
-        # Simulate Gemini Live syllable-by-syllable output with trailing newline
-        frames_to_send = [
-            BotStartedSpeakingFrame(),
-            SleepFrame(),
-            TTSTextFrame(text="Met"),
-            TTSTextFrame(text="amo"),
-            TTSTextFrame(text="rph"),
-            TTSTextFrame(text="osi"),
-            TTSTextFrame(text="s.\n"),  # Last fragment with trailing newline
-            BotStoppedSpeakingFrame(),
-        ]
-
-        expected_down_frames = [
-            BotStartedSpeakingFrame,
-            BotStoppedSpeakingFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TTSTextFrame,
-            TranscriptionUpdateFrame,
-        ]
-
-        await run_test(
-            processor,
-            frames_to_send=frames_to_send,
-            expected_down_frames=expected_down_frames,
-        )
-
-        # Verify syllables are concatenated without spaces and newline is stripped
-        self.assertEqual(len(received_updates), 1)
-        message = received_updates[0].messages[0]
-        self.assertEqual(message.role, "assistant")
-        self.assertEqual(message.content, "Metamorphosis.")