Refactor evolution config to remove allow_full_rewrites

Removed the allow_full_rewrites option from configuration and codebase, consolidating evolution mode selection under diff_based_evolution. Updated prompt sampling and controller logic to use diff_based_evolution exclusively, and adjusted example configs accordingly. Added a proposed validation snippet to prevent incompatible evolution settings.

Author: codelion

configs/default_config.yaml

@@ -11,7 +11,6 @@ random_seed: null                     # Random seed for reproducibility (null =
 
 # Evolution settings
 diff_based_evolution: true            # Use diff-based evolution (true) or full rewrites (false)
-allow_full_rewrites: false            # Allow occasional full rewrites even in diff-based mode
 max_code_length: 10000                # Maximum allowed code length in characters
 
 # LLM configuration

examples/signal_processing/claude-temp/proposed_config_fix.py

@@ -0,0 +1,60 @@
+"""
+PROPOSED FIX for OpenEvolve Configuration Bug
+
+Issue: diff_based_evolution=True and allow_full_rewrites=True are incompatible
+but no validation prevents this configuration from being used.
+
+PROBLEM:
+- Prompt sampler uses allow_full_rewrites to choose template
+- Controller uses diff_based_evolution to choose parser  
+- These can create contradictory behavior
+
+SOLUTION:
+Add validation to Config class __post_init__ method
+"""
+
+# Add this to openevolve/config.py in the Config class __post_init__ method:
+
+def __post_init__(self):
+    """Post-initialization validation"""
+    
+    # Validate evolution settings compatibility
+    if self.diff_based_evolution and self.allow_full_rewrites:
+        raise ValueError(
+            "Configuration Error: diff_based_evolution=True and allow_full_rewrites=True "
+            "are incompatible. Use one of these combinations:\n"
+            "  - diff_based_evolution=True, allow_full_rewrites=False (diff-based evolution)\n"
+            "  - diff_based_evolution=False, allow_full_rewrites=True (rewrite-based evolution)\n"
+            "  - diff_based_evolution=False, allow_full_rewrites=False (rewrite with diff template)"
+        )
+    
+    # Other existing validations...
+
+
+# Alternative: Add a helper method to validate and suggest fixes:
+
+def validate_evolution_settings(self) -> None:
+    """Validate evolution configuration and provide helpful error messages"""
+    
+    if self.diff_based_evolution and self.allow_full_rewrites:
+        suggested_configs = [
+            "# Option 1: Pure diff-based evolution (recommended for iterative improvements)",
+            "diff_based_evolution: true", 
+            "allow_full_rewrites: false",
+            "",
+            "# Option 2: Pure rewrite-based evolution (recommended for major changes)",
+            "diff_based_evolution: false",
+            "allow_full_rewrites: true"
+        ]
+        
+        raise ValueError(
+            f"❌ Configuration Error: Incompatible evolution settings detected!\n\n"
+            f"Current settings:\n"
+            f"  diff_based_evolution: {self.diff_based_evolution}\n" 
+            f"  allow_full_rewrites: {self.allow_full_rewrites}\n\n"
+            f"🔧 Suggested fixes:\n" + "\n".join(suggested_configs) + "\n\n"
+            f"💡 Explanation:\n"
+            f"  - diff_based_evolution=True makes the controller parse responses as diff blocks\n"
+            f"  - allow_full_rewrites=True makes the prompt ask for complete code rewrites\n" 
+            f"  - These create a contradiction: LLM returns complete code but controller expects diffs\n"
+        )

examples/signal_processing/config.yaml

@@ -1,18 +1,18 @@
 # Configuration for Real-Time Adaptive Signal Processing Example
-max_iterations: 200
-checkpoint_interval: 25
+max_iterations: 100
+checkpoint_interval: 10
 log_level: "INFO"
 
 # LLM configuration
 llm:
-  primary_model: "gemini-2.0-flash-lite"
+  primary_model: "gemini-2.5-flash-lite-preview-06-17"
   primary_model_weight: 0.8
   secondary_model: "gemini-2.5-flash"
   secondary_model_weight: 0.2
   api_base: "https://generativelanguage.googleapis.com/v1beta/openai/"
-  temperature: 0.7
+  temperature: 0.6
   top_p: 0.95
-  max_tokens: 4096
+  max_tokens: 32000
 
 # Prompt configuration
 prompt:
@@ -38,4 +38,4 @@ evaluator:
 
 # Evolution settings
 diff_based_evolution: true
-allow_full_rewrites: true
+max_code_length: 60000

openevolve/config.py

@@ -222,7 +222,6 @@ class Config:
 
     # Evolution settings
     diff_based_evolution: bool = True
-    allow_full_rewrites: bool = False
     max_code_length: int = 10000
 
     @classmethod
@@ -329,7 +328,6 @@ def to_dict(self) -> Dict[str, Any]:
             },
             # Evolution settings
             "diff_based_evolution": self.diff_based_evolution,
-            "allow_full_rewrites": self.allow_full_rewrites,
             "max_code_length": self.max_code_length,
         }
 

openevolve/controller.py

@@ -272,7 +272,7 @@ async def run(
                 top_programs=[p.to_dict() for p in inspirations],
                 language=self.language,
                 evolution_round=i,
-                allow_full_rewrite=self.config.allow_full_rewrites,
+                diff_based_evolution=self.config.diff_based_evolution,
                 program_artifacts=parent_artifacts if parent_artifacts else None,
             )
 
@@ -340,7 +340,7 @@ async def run(
                 # Log prompts
                 self.database.log_prompt(
                     template_key=(
-                        "full_rewrite_user" if self.config.allow_full_rewrites else "diff_user"
+                        "full_rewrite_user" if not self.config.diff_based_evolution else "diff_user"
                     ),
                     program_id=child_id,
                     prompt=prompt,
@@ -354,7 +354,7 @@ async def run(
                 # Log prompts
                 self.database.log_prompt(
                     template_key=(
-                        "full_rewrite_user" if self.config.allow_full_rewrites else "diff_user"
+                        "full_rewrite_user" if not self.config.diff_based_evolution else "diff_user"
                     ),
                     program_id=child_id,
                     prompt=prompt,

openevolve/prompt/sampler.py

@@ -53,7 +53,7 @@ def build_prompt(
         top_programs: List[Dict[str, Any]] = [],
         language: str = "python",
         evolution_round: int = 0,
-        allow_full_rewrite: bool = False,
+        diff_based_evolution: bool = True,
         template_key: Optional[str] = None,
         program_artifacts: Optional[Dict[str, Union[str, bytes]]] = None,
         **kwargs: Any,
@@ -69,24 +69,24 @@ def build_prompt(
             top_programs: List of top-performing programs
             language: Programming language
             evolution_round: Current evolution round
-            allow_full_rewrite: Whether to allow a full rewrite
+            diff_based_evolution: Whether to use diff-based evolution (True) or full rewrites (False)
             template_key: Optional override for template key
             program_artifacts: Optional artifacts from program evaluation
             **kwargs: Additional keys to replace in the user prompt
 
         Returns:
             Dictionary with 'system' and 'user' keys
         """
-        # Select template based on whether we want a full rewrite (with overrides)
+        # Select template based on evolution mode (with overrides)
         if template_key:
             # Use explicitly provided template key
             user_template_key = template_key
         elif self.user_template_override:
             # Use the override set with set_templates
             user_template_key = self.user_template_override
         else:
-            # Default behavior
-            user_template_key = "full_rewrite_user" if allow_full_rewrite else "diff_user"
+            # Default behavior: diff-based vs full rewrite
+            user_template_key = "diff_user" if diff_based_evolution else "full_rewrite_user"
 
         # Get the template
         user_template = self.template_manager.get_template(user_template_key)