Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

tests/agent/test_repetition_guard.py

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+"""Unit tests for the truncated-response repetition guard (issue #86581)."""
+
+from __future__ import annotations
+
+from agent.repetition_guard import MIN_FRAGMENT_LENGTH, is_repetition_dominated
+
+# The exact sentence from the #86581 incident (echoed hundreds of times by
+# the model before the provider cut it off at finish_reason=length).
+_INCIDENT_ECHO = "好，你幫我更改成 Google Gemini 4 31B。"
+
+
+class TestRepetitionGuard:
+    def test_incident_shape_flags_repetition(self):
+        # Narration + the echoed sentence on its own line, repeated (line path).
+        text = ("We need to verify the model setting.\n" + _INCIDENT_ECHO + "\n") * 800
+        assert is_repetition_dominated(text) is True
+
+    def test_repeated_sentence_without_line_breaks_flags(self):
+        # Repetition loop with no line breaks — exercises the window path.
+        text = _INCIDENT_ECHO * 2000
+        assert len(text) >= MIN_FRAGMENT_LENGTH
+        assert is_repetition_dominated(text) is True
+
+    def test_long_legitimate_text_not_flagged(self):
+        # Long, unique prose — no 60-char window ever repeats.
+        text = " ".join(
+            f"Sentence number {i} describes a distinct topic with unique words "
+            f"such as quasar-{i} and nebula-{i} to keep every window distinct."
+            for i in range(1200)
+        )
+        assert len(text) >= MIN_FRAGMENT_LENGTH
+        assert is_repetition_dominated(text) is False
+
+    def test_short_fragment_never_flagged(self):
+        # Below MIN_FRAGMENT_LENGTH the guard fails open — short truncations
+        # are legitimately continued even if they look repetitive.
+        assert is_repetition_dominated("A. " * 50) is False
+        assert is_repetition_dominated("hello ") is False
+
+    def test_repeat_not_dominant_not_flagged(self):
+        # A repeated sentence scattered through a long unique text: repeated
+        # windows exist but cover far less than half of the fragment.
+        filler = " ".join(f"unique filler token {i}" for i in range(3000))
+        text = filler + ("\n" + _INCIDENT_ECHO + "\n") * 30
+        assert is_repetition_dominated(text) is False
+
+    def test_non_string_inputs(self):
+        assert is_repetition_dominated("") is False
+        assert is_repetition_dominated(None) is False
+        assert is_repetition_dominated(12345) is False