Make max snapshot artifacts limit configurable (#386)

* Make max snapshot artifacts limit configurable

Add `database.max_snapshot_artifacts` config option to control how many
program artifacts are included in worker process snapshots. Default
remains 100 for backward compatibility.

- Set to a higher number to include more artifacts in prompts
- Set to `null` (None) for unlimited artifacts (use with caution for
  large populations as this can significantly increase memory usage)

Note: This limit only affects artifacts passed to worker processes,
not the total artifacts stored. All program code is always available
regardless of this setting.

Closes #383

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Add tests for recent features

Add comprehensive tests for recently merged PRs:

- test_llm_config_optional_params.py: Tests for optional temperature/top_p
  parameters (PR #385 - Anthropic model compatibility)

- test_snapshot_artifacts_limit.py: Tests for configurable max_snapshot_artifacts
  (PR #386)

- test_visualization_sanitization.py: Tests for -inf/+inf/NaN sanitization
  in visualization (PR #384)

- test_early_stopping_config.py: Tests for event-based early stopping
  configuration (PR #375)

- test_changes_description.py: Tests for large codebase support via
  changes description (PR #376)

Total tests increased from 264 to 326.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Add integration tests for example validation

Add comprehensive integration tests that verify:
- Example config files load correctly
- Initial programs have EVOLVE-BLOCK markers
- Evaluators exist and have required functions
- Evaluators can run on initial programs
- Cascade evaluation functions are detected
- Database stores and retrieves programs correctly
- Program evolution tracking works

Tests cover function_minimization, circle_packing, and signal_processing
examples, plus general structure validation for all examples.

Total tests: 346 (was 326)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: codelion

openevolve/config.py

@@ -340,6 +340,7 @@ class DatabaseConfig:
     artifact_size_threshold: int = 32 * 1024  # 32KB threshold
     cleanup_old_artifacts: bool = True
     artifact_retention_days: int = 30
+    max_snapshot_artifacts: Optional[int] = 100  # Max artifacts in worker snapshots (None=unlimited)
 
     novelty_llm: Optional["LLMInterface"] = None
     embedding_model: Optional[str] = None

openevolve/process_parallel.py

@@ -431,13 +431,18 @@ def _create_database_snapshot(self) -> Dict[str, Any]:
         }
 
         # Include artifacts for programs that might be selected
-        # IMPORTANT: This limits artifacts (execution outputs/errors) to first 100 programs only.
+        # This limits artifacts (execution outputs/errors) to avoid large snapshot sizes.
         # This does NOT affect program code - all programs are fully serialized above.
         # With max_artifact_bytes=20KB and population_size=1000, artifacts could be 20MB total,
-        # which would significantly slow worker process initialization. The limit of 100 keeps
-        # artifact data under 2MB while still providing execution context for recent programs.
+        # which would significantly slow worker process initialization. The default limit of 100
+        # keeps artifact data under 2MB while still providing execution context for recent programs.
         # Workers can still evolve properly as they have access to ALL program code.
-        for pid in list(self.database.programs.keys())[:100]:
+        # Configure via database.max_snapshot_artifacts (None for unlimited).
+        max_artifacts = self.database.config.max_snapshot_artifacts
+        program_ids = list(self.database.programs.keys())
+        if max_artifacts is not None:
+            program_ids = program_ids[:max_artifacts]
+        for pid in program_ids:
             artifacts = self.database.get_artifacts(pid)
             if artifacts:
                 snapshot["artifacts"][pid] = artifacts