fix(review): truncate raw_content in ContentFormatError message

Include truncated raw_content (first 500 chars) in exception message
for better debugging while avoiding unbounded output. Full content
remains accessible via the raw_content attribute. Update tests to
reflect the new message format and add truncation coverage test.

Refs: openai#2917

Author: giulio-leone

src/openai/_exceptions.py

@@ -179,13 +179,13 @@ class ContentFormatError(OpenAIError):
     def __init__(self, *, raw_content: str, error: Exception, response_format: object | None = None) -> None:
         expected_response_format = _response_format_name(response_format)
         expected_details = (
-            f" Expected response format: {expected_response_format}."
-            if expected_response_format is not None
-            else ""
+            f" Expected response format: {expected_response_format}." if expected_response_format is not None else ""
         )
+        truncated_content = raw_content[:500] + "..." if len(raw_content) > 500 else raw_content
         super().__init__(
             f"Could not parse response content as the response did not match the expected format."
-            f"{expected_details} Validation error: {_format_parse_error(error)}."
+            f"{expected_details} Raw content: {truncated_content!r}."
+            f" Validation error: {_format_parse_error(error)}."
         )
         self.raw_content = raw_content
         self.expected_response_format = expected_response_format
@@ -195,7 +195,12 @@ def __init__(self, *, raw_content: str, error: Exception, response_format: objec
 def _response_format_name(response_format: object | None) -> str | None:
     if response_format is None:
         return None
-    return cast(str, getattr(response_format, "__name__", None) or getattr(response_format, "__qualname__", None) or repr(response_format))
+    return cast(
+        str,
+        getattr(response_format, "__name__", None)
+        or getattr(response_format, "__qualname__", None)
+        or repr(response_format),
+    )
 
 
 def _format_parse_error(error: Exception) -> str:

tests/lib/chat/test_completions.py

@@ -575,7 +575,7 @@ class Location(BaseModel):
         )
     assert '{"city": "San' in exc_info.value.raw_content
     assert exc_info.value.expected_response_format == "Location"
-    assert '{"city": "San' not in str(exc_info.value)
+    assert "Raw content:" in str(exc_info.value)
 
 
 @pytest.mark.respx(base_url=base_url)
@@ -606,7 +606,21 @@ class Location(BaseModel):
         )
     assert exc_info.value.raw_content == '{"city": "San Francisco"}'
     assert exc_info.value.expected_response_format == "Location"
-    assert '{"city": "San Francisco"}' not in str(exc_info.value)
+    assert "Raw content:" in str(exc_info.value)
+
+
+def test_content_format_error_truncates_raw_content() -> None:
+    """Verify raw_content is truncated in the exception message for very large payloads."""
+    long_content = "x" * 1000
+    err = openai.ContentFormatError(raw_content=long_content, error=ValueError("bad"), response_format=None)
+    msg = str(err)
+    # Full raw_content is preserved on the attribute
+    assert len(err.raw_content) == 1000
+    # Message should contain truncated version (500 chars + "...")
+    assert "xxx..." in msg
+    assert len(long_content) > 500  # sanity
+    # Should not contain the full 1000-char string in the message
+    assert long_content not in msg
 
 
 @pytest.mark.respx(base_url=base_url)