feat: dead code detector for Python codebases (#94)

scripts/dead_code_detector.py

@@ -0,0 +1,282 @@
+#!/usr/bin/env python3
+"""
+Dead Code Detector for Python Codebases
+
+AST-based analysis to find defined but never-called functions and classes.
+Excludes entry points, plugin hooks, __init__ exports.
+
+Usage:
+  python3 scripts/dead_code_detector.py /path/to/repo/
+  python3 scripts/dead_code_detector.py hermes-agent/ --format json
+  python3 scripts/dead_code_detector.py . --exclude tests/,venv/
+
+Output: file:line, function/class name, last git author (if available)
+"""
+
+import argparse
+import ast
+import json
+import os
+import subprocess
+import sys
+from collections import defaultdict
+from pathlib import Path
+from typing import Optional
+
+
+# Names that are expected to be unused (entry points, protocol methods, etc.)
+SAFE_UNUSED_PATTERNS = {
+    # Python dunders
+    "__init__", "__str__", "__repr__", "__eq__", "__hash__", "__len__",
+    "__getitem__", "__setitem__", "__contains__", "__iter__", "__next__",
+    "__enter__", "__exit__", "__call__", "__bool__", "__del__",
+    "__post_init__", "__class_getitem__",
+    # Common entry points
+    "main", "app", "handler", "setup", "teardown", "fixture",
+    # pytest
+    "conftest", "test_", "pytest_",  # prefix patterns
+    # Protocols / abstract
+    "abstractmethod", "abc_",
+}
+
+
+def is_safe_unused(name: str, filepath: str) -> bool:
+    """Check if an unused name is expected to be unused."""
+    # Test files are exempt
+    if "test" in filepath.lower():
+        return True
+
+    # Known patterns
+    for pattern in SAFE_UNUSED_PATTERNS:
+        if name.startswith(pattern) or name == pattern:
+            return True
+
+    # __init__.py exports are often unused internally
+    if filepath.endswith("__init__.py"):
+        return True
+
+    return False
+
+
+def get_git_blame(filepath: str, lineno: int) -> Optional[str]:
+    """Get last author of a line via git blame."""
+    try:
+        result = subprocess.run(
+            ["git", "blame", "-L", f"{lineno},{lineno}", "--porcelain", filepath],
+            capture_output=True, text=True, timeout=5
+        )
+        for line in result.stdout.split("\n"):
+            if line.startswith("author "):
+                return line[7:]
+    except:
+        pass
+    return None
+
+
+class DefinitionCollector(ast.NodeVisitor):
+    """Collect all function and class definitions."""
+
+    def __init__(self):
+        self.definitions = []  # (name, type, lineno, filepath)
+
+    def visit_FunctionDef(self, node):
+        self.definitions.append((node.name, "function", node.lineno))
+        self.generic_visit(node)
+
+    def visit_AsyncFunctionDef(self, node):
+        self.definitions.append((node.name, "async_function", node.lineno))
+        self.generic_visit(node)
+
+    def visit_ClassDef(self, node):
+        self.definitions.append((node.name, "class", node.lineno))
+        self.generic_visit(node)
+
+
+class NameUsageCollector(ast.NodeVisitor):
+    """Collect all name references (calls, imports, attribute access)."""
+
+    def __init__(self):
+        self.names = set()
+        self.calls = set()
+        self.imports = set()
+
+    def visit_Name(self, node):
+        self.names.add(node.id)
+        self.generic_visit(node)
+
+    def visit_Attribute(self, node):
+        if isinstance(node.value, ast.Name):
+            self.names.add(node.value.id)
+        self.generic_visit(node)
+
+    def visit_Call(self, node):
+        if isinstance(node.func, ast.Name):
+            self.calls.add(node.func.id)
+        elif isinstance(node.func, ast.Attribute):
+            if isinstance(node.func.value, ast.Name):
+                self.names.add(node.func.value.id)
+            self.calls.add(node.func.attr)
+        self.generic_visit(node)
+
+    def visit_Import(self, node):
+        for alias in node.names:
+            self.imports.add(alias.asname or alias.name)
+        self.generic_visit(node)
+
+    def visit_ImportFrom(self, node):
+        for alias in node.names:
+            self.imports.add(alias.asname or alias.name)
+        self.generic_visit(node)
+
+
+def analyze_file(filepath: str) -> dict:
+    """Analyze a single Python file for dead code."""
+    path = Path(filepath)
+    try:
+        content = path.read_text()
+        tree = ast.parse(content, filename=str(filepath))
+    except (SyntaxError, UnicodeDecodeError):
+        return {"error": f"Could not parse {filepath}"}
+
+    # Collect definitions
+    def_collector = DefinitionCollector()
+    def_collector.visit(tree)
+    definitions = def_collector.definitions
+
+    # Collect usage
+    usage_collector = NameUsageCollector()
+    usage_collector.visit(tree)
+    used_names = usage_collector.names | usage_collector.calls | usage_collector.imports
+
+    # Also scan the entire repo for references to this file's definitions
+    # (this is done at the repo level, not file level)
+
+    dead = []
+    for name, def_type, lineno in definitions:
+        if name.startswith("_") and not name.startswith("__"):
+            # Private functions — might be used externally, less likely dead
+            pass
+
+        if name not in used_names:
+            if not is_safe_unused(name, filepath):
+                dead.append({
+                    "name": name,
+                    "type": def_type,
+                    "file": filepath,
+                    "line": lineno,
+                })
+
+    return {"definitions": len(definitions), "dead": dead}
+
+
+def scan_repo(repo_path: str, exclude_patterns: list = None) -> dict:
+    """Scan an entire repo for dead code."""
+    path = Path(repo_path)
+    exclude = exclude_patterns or ["venv", ".venv", "node_modules", "__pycache__",
+                                    ".git", "dist", "build", ".tox", "vendor"]
+
+    all_definitions = {}  # name -> [{file, line, type}]
+    all_files = []
+    dead_code = []
+
+    # First pass: collect all definitions across repo
+    for fpath in path.rglob("*.py"):
+        parts = fpath.parts
+        if any(ex in parts for ex in exclude):
+            continue
+        if fpath.name.startswith("."):
+            continue
+
+        try:
+            content = fpath.read_text(errors="ignore")
+            tree = ast.parse(content, filename=str(fpath))
+        except:
+            continue
+
+        all_files.append(str(fpath))
+        collector = DefinitionCollector()
+        collector.visit(tree)
+
+        for name, def_type, lineno in collector.definitions:
+            rel_path = str(fpath.relative_to(path))
+            if name not in all_definitions:
+                all_definitions[name] = []
+            all_definitions[name].append({
+                "file": rel_path,
+                "line": lineno,
+                "type": def_type,
+            })
+
+    # Second pass: check each name for usage across entire repo
+    all_used_names = set()
+    for fpath_str in all_files:
+        try:
+            content = Path(fpath_str).read_text(errors="ignore")
+            tree = ast.parse(content)
+        except:
+            continue
+        usage = NameUsageCollector()
+        usage.visit(tree)
+        all_used_names.update(usage.names)
+        all_used_names.update(usage.calls)
+        all_used_names.update(usage.imports)
+
+    # Find dead code
+    for name, locations in all_definitions.items():
+        if name not in all_used_names:
+            for loc in locations:
+                if not is_safe_unused(name, loc["file"]):
+                    dead_code.append({
+                        "name": name,
+                        "type": loc["type"],
+                        "file": loc["file"],
+                        "line": loc["line"],
+                    })
+
+    return {
+        "repo": path.name,
+        "files_scanned": len(all_files),
+        "total_definitions": sum(len(v) for v in all_definitions.values()),
+        "dead_code_count": len(dead_code),
+        "dead_code": sorted(dead_code, key=lambda x: (x["file"], x["line"])),
+    }
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Find dead code in Python codebases")
+    parser.add_argument("repo", help="Repository path to scan")
+    parser.add_argument("--format", choices=["text", "json"], default="text")
+    parser.add_argument("--exclude", help="Comma-separated patterns to exclude")
+    parser.add_argument("--git-blame", action="store_true", help="Include git blame info")
+    args = parser.parse_args()
+
+    exclude = args.exclude.split(",") if args.exclude else None
+    result = scan_repo(args.repo, exclude)
+
+    if args.format == "json":
+        print(json.dumps(result, indent=2))
+    else:
+        print(f"Dead Code Report: {result['repo']}")
+        print(f"Files scanned: {result['files_scanned']}")
+        print(f"Total definitions: {result['total_definitions']}")
+        print(f"Dead code found: {result['dead_code_count']}")
+        print()
+
+        if result["dead_code"]:
+            print(f"{'File':<45} {'Line':>4} {'Type':<10} {'Name'}")
+            print("-" * 85)
+            for item in result["dead_code"]:
+                author = ""
+                if args.git_blame:
+                    author = get_git_blame(
+                        os.path.join(args.repo, item["file"]),
+                        item["line"]
+                    ) or ""
+                    author = f" ({author})" if author else ""
+                print(f"{item['file']:<45} {item['line']:>4} {item['type']:<10} {item['name']}{author}")
+        else:
+            print("No dead code detected!")
+
+
+if __name__ == "__main__":
+    main()

scripts/session_metadata.py

@@ -1,276 +0,0 @@
-#!/usr/bin/env python3
-"""
-session_metadata.py - Extract structured metadata from Hermes session transcripts.
-Works alongside session_reader.py to provide higher-level session analysis.
-"""
-
-import json
-import re
-import sys
-from dataclasses import dataclass, asdict
-from datetime import datetime
-from pathlib import Path
-from typing import Dict, List, Optional, Any
-
-# Import from session_reader (the canonical reader)
-from session_reader import read_session
-
-
-@dataclass
-class SessionSummary:
-    """Structured summary of a Hermes session transcript."""
-    session_id: str
-    model: str
-    repo: str
-    outcome: str
-    message_count: int
-    tool_calls: int
-    duration_estimate: str
-    key_actions: List[str]
-    errors_encountered: List[str]
-    start_time: Optional[str] = None
-    end_time: Optional[str] = None
-    total_tokens_estimate: int = 0
-    user_messages: int = 0
-    assistant_messages: int = 0
-    tool_outputs: int = 0
-
-
-def extract_session_metadata(file_path: str) -> SessionSummary:
-    """
-    Extract structured metadata from a Hermes session JSONL transcript.
-    Uses session_reader.read_session() for file reading.
-    """
-    session_id = Path(file_path).stem
-    messages = []
-    model = "unknown"
-    repo = "unknown"
-    tool_calls_count = 0
-    key_actions = []
-    errors = []
-    start_time = None
-    end_time = None
-    total_tokens = 0
-    
-    # Common repo patterns to look for
-    repo_patterns = [
-        r"(?:the-nexus|compounding-intelligence|timmy-config|hermes-agent)",
-        r"(?:forge\.alexanderwhitestone\.com/([^/]+/[^/\\s]+))",
-        r"(?:github\.com/([^/]+/[^/\\s]+))",
-        r"(?:Timmy_Foundation/([^/\\s]+))",
-    ]
-    
-    try:
-        # Use the canonical reader from session_reader.py
-        messages = read_session(file_path)
-    except FileNotFoundError:
-        return SessionSummary(
-            session_id=session_id,
-            model="unknown",
-            repo="unknown",
-            outcome="failure",
-            message_count=0,
-            tool_calls=0,
-            duration_estimate="0m",
-            key_actions=[],
-            errors_encountered=[f"File not found: {file_path}"]
-        )
-    
-    # Process messages for metadata
-    for entry in messages:
-        # Extract model from assistant messages
-        if entry.get("role") == "assistant" and entry.get("model"):
-            model = entry["model"]
-        
-        # Extract timestamps
-        if entry.get("timestamp"):
-            ts = entry["timestamp"]
-            if start_time is None:
-                start_time = ts
-            end_time = ts
-        
-        # Count tool calls
-        if entry.get("tool_calls"):
-            tool_calls_count += len(entry["tool_calls"])
-            for tc in entry["tool_calls"]:
-                if tc.get("function", {}).get("name"):
-                    action = f"{tc['function']['name']}"
-                    if action not in key_actions:
-                        key_actions.append(action)
-        
-        # Estimate tokens from content length
-        content = entry.get("content", "")
-        if isinstance(content, str):
-            total_tokens += len(content.split())
-        elif isinstance(content, list):
-            for item in content:
-                if isinstance(item, dict) and "text" in item:
-                    total_tokens += len(item["text"].split())
-        
-        # Look for repo mentions in content
-        if entry.get("content"):
-            content_str = str(entry["content"])
-            for pattern in repo_patterns:
-                match = re.search(pattern, content_str, re.IGNORECASE)
-                if match:
-                    if match.groups():
-                        repo = match.group(1)
-                    else:
-                        repo = match.group(0)
-                    break
-        
-        # Look for error messages
-        if entry.get("role") == "tool" and entry.get("is_error"):
-            error_msg = entry.get("content", "Unknown error")
-            if isinstance(error_msg, str) and len(error_msg) < 200:
-                errors.append(error_msg[:200])
-    
-    # Count message types
-    user_messages = sum(1 for m in messages if m.get("role") == "user")
-    assistant_messages = sum(1 for m in messages if m.get("role") == "assistant")
-    tool_outputs = sum(1 for m in messages if m.get("role") == "tool")
-    
-    # Calculate duration estimate
-    duration_estimate = "unknown"
-    if start_time and end_time:
-        try:
-            # Try to parse timestamps
-            start_dt = None
-            end_dt = None
-            
-            # Handle various timestamp formats
-            for fmt in ["%Y-%m-%dT%H:%M:%S.%fZ", "%Y-%m-%dT%H:%M:%SZ", "%Y-%m-%d %H:%M:%S"]:
-                try:
-                    if start_dt is None:
-                        start_dt = datetime.strptime(start_time, fmt)
-                    if end_dt is None:
-                        end_dt = datetime.strptime(end_time, fmt)
-                except ValueError:
-                    continue
-            
-            if start_dt and end_dt:
-                duration = end_dt - start_dt
-                minutes = duration.total_seconds() / 60
-                duration_estimate = f"{minutes:.0f}m"
-        except Exception:
-            pass
-    
-    # Classify outcome
-    outcome = "unknown"
-    if errors:
-        # Check if any errors are fatal
-        fatal_errors = any("405" in e or "permission" in e.lower() or "authentication" in e.lower() 
-                          for e in errors)
-        if fatal_errors:
-            outcome = "failure"
-        else:
-            outcome = "partial"
-    elif messages:
-        # Check last message for success indicators
-        last_msg = messages[-1]
-        if last_msg.get("role") == "assistant":
-            content = last_msg.get("content", "")
-            if isinstance(content, str):
-                success_indicators = ["done", "completed", "success", "merged", "pushed"]
-                if any(indicator in content.lower() for indicator in success_indicators):
-                    outcome = "success"
-                else:
-                    outcome = "unknown"
-    
-    # Deduplicate key actions (keep unique, limit to 10)
-    unique_actions = []
-    for action in key_actions:
-        if action not in unique_actions:
-            unique_actions.append(action)
-        if len(unique_actions) >= 10:
-            break
-    
-    # Deduplicate errors (keep unique, limit to 5)
-    unique_errors = []
-    for error in errors:
-        if error not in unique_errors:
-            unique_errors.append(error)
-        if len(unique_errors) >= 5:
-            break
-    
-    return SessionSummary(
-        session_id=session_id,
-        model=model,
-        repo=repo,
-        outcome=outcome,
-        message_count=len(messages),
-        tool_calls=tool_calls_count,
-        duration_estimate=duration_estimate,
-        key_actions=unique_actions,
-        errors_encountered=unique_errors,
-        start_time=start_time,
-        end_time=end_time,
-        total_tokens_estimate=total_tokens,
-        user_messages=user_messages,
-        assistant_messages=assistant_messages,
-        tool_outputs=tool_outputs
-    )
-
-
-def process_session_directory(directory_path: str, output_file: Optional[str] = None) -> List[SessionSummary]:
-    """
-    Process all JSONL files in a directory.
-    """
-    directory = Path(directory_path)
-    if not directory.exists():
-        print(f"Error: Directory {directory_path} does not exist", file=sys.stderr)
-        return []
-    
-    jsonl_files = list(directory.glob("*.jsonl"))
-    if not jsonl_files:
-        print(f"Warning: No JSONL files found in {directory_path}", file=sys.stderr)
-        return []
-    
-    summaries = []
-    for jsonl_file in sorted(jsonl_files):
-        print(f"Processing {jsonl_file.name}...", file=sys.stderr)
-        summary = extract_session_metadata(str(jsonl_file))
-        summaries.append(summary)
-    
-    if output_file:
-        with open(output_file, 'w', encoding='utf-8') as f:
-            json.dump([asdict(s) for s in summaries], f, indent=2)
-        print(f"Wrote {len(summaries)} summaries to {output_file}", file=sys.stderr)
-    
-    return summaries
-
-
-def main():
-    """CLI entry point."""
-    import argparse
-    
-    parser = argparse.ArgumentParser(description="Extract metadata from Hermes session JSONL transcripts")
-    parser.add_argument("path", help="Path to JSONL file or directory of session files")
-    parser.add_argument("-o", "--output", help="Output JSON file (default: stdout)")
-    parser.add_argument("-v", "--verbose", action="store_true", help="Verbose output")
-    
-    args = parser.parse_args()
-    
-    path = Path(args.path)
-    
-    if path.is_file():
-        summary = extract_session_metadata(str(path))
-        if args.output:
-            with open(args.output, 'w') as f:
-                json.dump(asdict(summary), f, indent=2)
-            print(f"Wrote summary to {args.output}", file=sys.stderr)
-        else:
-            print(json.dumps(asdict(summary), indent=2))
-    
-    elif path.is_dir():
-        summaries = process_session_directory(str(path), args.output)
-        if not args.output:
-            print(json.dumps([asdict(s) for s in summaries], indent=2))
-    
-    else:
-        print(f"Error: {args.path} is not a file or directory", file=sys.stderr)
-        sys.exit(1)
-
-
-if __name__ == "__main__":
-    main()