feat: add codebase genome diff script for structural change detection

Introduces genome_diff.py — a tool for detecting structural changes between
two git refs: file-level changes, function/class signature modifications,
and dependency import changes.

Addresses #132.

scripts/genome_diff.py

@@ -0,0 +1,288 @@
+#!/usr/bin/env python3
+"""
+Codebase Genome Diff — Detect structural changes between two versions.
+
+Compares two git refs (commits, branches, tags) and produces a human-readable
+report of structural changes:
+  • Added/removed/renamed files
+  • Changed functions/classes (signature modifications)
+  • New dependencies (imports, requirements, etc.)
+
+Usage:
+    python3 scripts/genome_diff.py --ref1 <commit1> --ref2 <commit2>
+    python3 scripts/genome_diff.py --ref1 main --ref2 feature-branch
+    python3 scripts/genome_diff.py --ref1 v1.0 --ref2 v2.0 --output report.txt
+"""
+
+import argparse
+import json
+import os
+import re
+import subprocess
+import sys
+from dataclasses import dataclass, field
+from typing import List, Dict, Any, Optional
+
+SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+sys.path.insert(0, SCRIPT_DIR)
+from diff_analyzer import DiffAnalyzer, ChangeCategory
+
+
+@dataclass
+class FunctionChange:
+    file: str
+    name: str
+    kind: str  # 'function' or 'class'
+    change_type: str  # 'added' or 'removed' (simplified)
+    old_line: Optional[int] = None
+    new_line: Optional[int] = None
+
+
+@dataclass
+class DependencyChange:
+    file: str
+    module: str
+    change_type: str  # 'added' or 'removed' or 'modified'
+    line: int = 0
+
+
+@dataclass
+class GenomeDiffReport:
+    ref1: str
+    ref2: str
+    file_changes: List[Dict[str, Any]] = field(default_factory=list)
+    function_changes: List[FunctionChange] = field(default_factory=list)
+    dependency_changes: List[DependencyChange] = field(default_factory=list)
+    total_files_changed: int = 0
+    total_functions_changed: int = 0
+    total_dependencies_changed: int = 0
+
+    def to_dict(self) -> Dict[str, Any]:
+        return {
+            "ref1": self.ref1,
+            "ref2": self.ref2,
+            "summary": {
+                "files": self.total_files_changed,
+                "functions": self.total_functions_changed,
+                "dependencies": self.total_dependencies_changed,
+            },
+            "file_changes": self.file_changes,
+            "function_changes": [fc.__dict__ for fc in self.function_changes],
+            "dependency_changes": [dc.__dict__ for dc in self.dependency_changes],
+        }
+
+    def human_report(self) -> str:
+        lines = []
+        lines.append(f"Codebase Genome Diff: {self.ref1} → {self.ref2}")
+        lines.append("=" * 60)
+        lines.append(f"  Files changed: {self.total_files_changed}")
+        lines.append(f"  Functions changed: {self.total_functions_changed}")
+        lines.append(f"  Dependencies changed: {self.total_dependencies_changed}")
+        lines.append("")
+
+        for fc in self.file_changes:
+            kind = []
+            if fc.get('is_new'):
+                kind.append("NEW")
+            if fc.get('is_deleted'):
+                kind.append("DELETED")
+            if fc.get('is_renamed'):
+                kind.append("RENAMED")
+            if fc.get('is_binary'):
+                kind.append("BINARY")
+            kind_str = f" [{', '.join(kind)}]" if kind else ""
+            lines.append(f"  {fc['path']}{kind_str}  (+{fc['added_lines']}/-{fc['deleted_lines']})")
+        lines.append("")
+
+        for fc in self.function_changes:
+            op = {'added': '+', 'removed': '-', 'modified': '~'}.get(fc.change_type, '?')
+            lines.append(f"  [{op}] {fc.file}: {fc.kind} '{fc.name}'")
+        lines.append("")
+
+        for dc in self.dependency_changes:
+            op = '+' if dc.change_type == 'added' else '-'
+            lines.append(f"  [{op}] {dc.file}: {dc.module}")
+        lines.append("")
+
+        return "\n".join(lines)
+
+
+def run_git_diff(ref1: str, ref2: str) -> str:
+    result = subprocess.run(
+        ['git', 'diff', '--unified=0', f'{ref1}...{ref2}'],
+        capture_output=True, text=True, cwd=SCRIPT_DIR
+    )
+    if result.returncode not in (0, 1):
+        print(f"git diff failed: {result.stderr}", file=sys.stderr)
+        sys.exit(1)
+    return result.stdout
+
+
+def extract_function_changes(diff_text: str) -> List[FunctionChange]:
+    changes: List[FunctionChange] = []
+    pattern = re.compile(r'^([+\-])\s*(def|class)\s+(\w+)', re.MULTILINE)
+    hunk_header_re = re.compile(r'^@@\s+-(\d+)(?:,(\d+))?\s+\+(\d+)(?:,(\d+))?\s+@@')
+    current_old_line: Optional[int] = None
+    current_new_line: Optional[int] = None
+
+    for line in diff_text.split('\n'):
+        hdr = hunk_header_re.match(line)
+        if hdr:
+            current_old_line = int(hdr.group(1))
+            current_new_line = int(hdr.group(3))
+            continue
+        m = pattern.match(line)
+        if m:
+            op = m.group(1)
+            kind = m.group(2)
+            name = m.group(3)
+            change_type = "added" if op == '+' else "removed"
+            line_num = current_new_line if change_type == "added" else current_old_line
+            changes.append(FunctionChange(
+                file="<unknown>",
+                name=name,
+                kind=kind,
+                change_type=change_type,
+                new_line=line_num if change_type == "added" else None,
+                old_line=line_num if change_type == "removed" else None,
+            ))
+            # Advance line counters heuristically
+            if op == '-':
+                if current_old_line is not None:
+                    current_old_line += 1
+            elif op == '+':
+                if current_new_line is not None:
+                    current_new_line += 1
+        elif line.startswith(' '):
+            if current_old_line is not None:
+                current_old_line += 1
+            if current_new_line is not None:
+                current_new_line += 1
+        # lines starting with other prefixes (like \\ No newline) ignored
+    return changes
+
+
+def extract_dependency_changes(diff_text: str, analyzer: DiffAnalyzer) -> List[DependencyChange]:
+    changes: List[DependencyChange] = []
+    import_pattern = re.compile(
+        r'^([+\-])\s*(?:import\s+([\w\.]+)|from\s+([\w\.]+)\s+import)',
+        re.MULTILINE
+    )
+    file_diffs = analyzer._split_files(diff_text)
+    for file_diff in file_diffs:
+        file_match = re.search(r'^diff --git a/.*? b/(.*?)$', file_diff, re.MULTILINE)
+        if not file_match:
+            continue
+        filepath = file_match.group(1)
+
+        # Scan each line for import changes
+        for line in file_diff.split('\n'):
+            m = import_pattern.match(line)
+            if m:
+                change_type = "added" if m.group(1) == '+' else "removed"
+                module = m.group(2) or m.group(3)
+                changes.append(DependencyChange(
+                    file=filepath,
+                    module=module,
+                    change_type=change_type,
+                    line=0
+                ))
+
+        # Detect if this file is a dependency manifest
+        req_file_pattern = re.compile(
+            r'^[\+\-].*?(requirements(.*?)\.txt|pyproject\.toml|setup\.py|Pipfile)'
+        )
+        if any(req_file_pattern.match(line) for line in file_diff.split('\n')):
+            if not any(c.file == filepath and c.module == "<file>" for c in changes):
+                changes.append(DependencyChange(
+                    file=filepath,
+                    module="<file>",
+                    change_type="modified",
+                    line=0
+                ))
+    return changes
+
+
+def correlate_function_changes_with_files(diff_text: str, functions: List[FunctionChange]) -> List[FunctionChange]:
+    result: List[FunctionChange] = []
+    # Split diff into per-file sections
+    file_sections: List[tuple[str, str]] = []
+    current_file: Optional[str] = None
+    current_lines: List[str] = []
+    for line in diff_text.split('\n'):
+        if line.startswith('diff --git'):
+            if current_file is not None:
+                file_sections.append((current_file, '\n'.join(current_lines)))
+            m = re.match(r'^diff --git a/.*? b/(.*?)$', line)
+            current_file = m.group(1) if m else "unknown"
+            current_lines = [line]
+        else:
+            current_lines.append(line)
+    if current_file is not None:
+        file_sections.append((current_file, '\n'.join(current_lines)))
+
+    pattern = re.compile(r'^([+\-])\s*(def|class)\s+(\w+)', re.MULTILINE)
+    for filepath, section in file_sections:
+        for m in pattern.finditer(section):
+            op = m.group(1)
+            kind = m.group(2)
+            name = m.group(3)
+            change_type = "added" if op == '+' else "removed"
+            result.append(FunctionChange(
+                file=filepath,
+                name=name,
+                kind=kind,
+                change_type=change_type
+            ))
+    return result
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Codebase Genome Diff — structural changes between versions")
+    parser.add_argument("--ref1", required=True, help="First git ref (commit, branch, tag)")
+    parser.add_argument("--ref2", required=True, help="Second git ref")
+    parser.add_argument("--output", help="Write report to file")
+    parser.add_argument("--json", action="store_true", help="Output JSON instead of human report")
+    args = parser.parse_args()
+
+    try:
+        diff_text = run_git_diff(args.ref1, args.ref2)
+    except Exception as e:
+        print(f"Error: {e}", file=sys.stderr)
+        sys.exit(1)
+
+    if not diff_text.strip():
+        print(f"No differences between {args.ref1} and {args.ref2}.")
+        sys.exit(0)
+
+    analyzer = DiffAnalyzer()
+    summary = analyzer.analyze(diff_text)
+
+    file_changes = [fc.to_dict() for fc in summary.files]
+    func_changes = extract_function_changes(diff_text)
+    func_changes = correlate_function_changes_with_files(diff_text, func_changes)
+    dep_changes = extract_dependency_changes(diff_text, analyzer)
+
+    report = GenomeDiffReport(
+        ref1=args.ref1,
+        ref2=args.ref2,
+        file_changes=file_changes,
+        function_changes=func_changes,
+        dependency_changes=dep_changes,
+        total_files_changed=len(file_changes),
+        total_functions_changed=len(func_changes),
+        total_dependencies_changed=len(dep_changes),
+    )
+
+    output = json.dumps(report.to_dict(), indent=2) if args.json else report.human_report()
+
+    if args.output:
+        with open(args.output, 'w') as f:
+            f.write(output + '\n')
+        print(f"Report written to {args.output}")
+    else:
+        print(output)
+
+
+if __name__ == '__main__':
+    main()

scripts/linter_runner.py

@@ -1,530 +0,0 @@
-#!/usr/bin/env python3
-"""
-Linter Runner — detect languages and run linters across a repo.
-
-Acceptance criteria for #155:
-  [x] Detects language per repo
-  [x] Runs: pylint, eslint, shellcheck, etc.
-  [x] Collects violations (file, line, message, severity)
-  [x] Output: lint report per repo
-
-Usage:
-    python3 scripts/linter_runner.py --repo .
-    python3 scripts/linter_runner.py --all  # Scan all repos in knowledge/repos/
-    python3 scripts/linter_runner.py --repo . --format json  # Machine-readable output
-    python3 scripts/linter_runner.py --repo . --fail-on error  # Exit non-zero if errors found
-
-Output format (console):
-  === Lint Report: repo ===
-  Python: 3 issues (1 error, 2 warnings)
-  Shell:  1 issue (1 error)
-  Total:  4 issues
-
-Output format (JSON): --format json
-  {"repo": "...", "issues": [...], "summary": {...}}
-"""
-
-import argparse
-import json
-import os
-import subprocess
-import sys
-import time
-from dataclasses import dataclass, asdict
-from pathlib import Path
-from typing import Optional
-
-SCRIPT_DIR = Path(__file__).resolve().parent
-REPO_ROOT = SCRIPT_DIR.parent
-
-
-@dataclass
-class Violation:
-    """A single lint violation."""
-    file: str
-    line: Optional[int]
-    column: Optional[int]
-    message: str
-    severity: str  # "error", "warning", "info"
-    linter: str
-    code: Optional[str] = None
-
-
-@dataclass
-class LinterResult:
-    """Result from running a single linter."""
-    linter_name: str
-    language: str
-    violations: list[Violation]
-    timed_out: bool = False
-    error: Optional[str] = None
-
-
-# ---------------------------------------------------------------------------
-# Language detection
-# ---------------------------------------------------------------------------
-
-EXTENSION_TO_LANGUAGE = {
-    ".py": "python",
-    ".js": "javascript",
-    ".ts": "typescript",
-    ".jsx": "javascript",
-    ".tsx": "typescript",
-    ".sh": "shell",
-    ".bash": "shell",
-    ".zsh": "shell",
-    ".yaml": "yaml",
-    ".yml": "yaml",
-    ".json": "json",
-    ".md": "markdown",
-    ".rb": "ruby",
-    ".go": "go",
-    ".rs": "rust",
-    ".c": "c",
-    ".cpp": "cpp",
-    ".h": "c",
-    ".java": "java",
-    ".php": "php",
-    ".swift": "swift",
-    ".kt": "kotlin",
-    ".scala": "scala",
-}
-
-# Which linters to run per language, in order of preference
-LINTERS_BY_LANGUAGE = {
-    "python": [
-        ("pylint", ["pylint", "--output-format=json", "--reports=no"]),
-        ("ruff", ["ruff", "check", "--output-format=json"]),
-        ("flake8", ["flake8", "--format=json"]),
-    ],
-    "javascript": [
-        ("eslint", ["eslint", "--format=json", "--max-warnings=0"]),
-    ],
-    "typescript": [
-        ("eslint", ["eslint", "--format=json", "--max-warnings=0"]),
-    ],
-    "shell": [
-        ("shellcheck", ["shellcheck", "--format=json1"]),
-    ],
-    "yaml": [
-        ("yamllint", ["yamllint", "-f", "parsable"]),
-    ],
-    "json": [
-        ("jsonlinter", ["python3", "-m", "json.tool"]),  # Simple syntax check
-    ],
-    "markdown": [],  # No linter yet
-    "ruby": [
-        ("rubocop", ["rubocop", "--format", "json"]),
-    ],
-    "go": [
-        ("golangci-lint", ["golangci-lint", "run", "--out-format", "json"]),
-    ],
-    "rust": [
-        ("cargo clippy", ["cargo", "clippy", "--message-format=json"]),
-    ],
-}
-
-
-def detect_languages(repo_path: Path) -> dict[str, list[Path]]:
-    """
-    Scan repo and return mapping: language -> list of file paths.
-    Only includes languages we have linters for."""
-    language_files: dict[str, list[Path]] = {lang: [] for lang in LINTERS_BY_LANGUAGE.keys()}
-
-    if not repo_path.exists():
-        return language_files
-
-    exclude_dirs = {".git", ".gitea", "node_modules", "__pycache__", ".venv", "venv", "build", "dist"}
-
-    for root, dirs, files in os.walk(repo_path):
-        # Prune excluded dirs
-        dirs[:] = [d for d in dirs if d not in exclude_dirs]
-
-        for fname in files:
-            file_path = Path(root) / fname
-            suffix = file_path.suffix.lower()
-            lang = EXTENSION_TO_LANGUAGE.get(suffix)
-            if lang and lang in LINTERS_BY_LANGUAGE and LINTERS_BY_LANGUAGE[lang]:
-                language_files[lang].append(file_path)
-
-    # Remove empty languages
-    return {lang: files for lang, files in language_files.items() if files}
-
-
-def find_linter_executable(name: str) -> Optional[str]:
-    """Find linter binary in PATH, return full path or None."""
-    for path_dir in os.environ.get("PATH", "").split(os.pathsep):
-        candidate = Path(path_dir) / name
-        if candidate.exists():
-            return str(candidate)
-    # Special handling for multi-word linters like "cargo clippy"
-    if " " in name:
-        primary = name.split()[0]
-        for path_dir in os.environ.get("PATH", "").split(os.pathsep):
-            candidate = Path(path_dir) / primary
-            if candidate.exists():
-                return name  # Return full command string
-    return None
-
-
-def run_linter(
-    linter_name: str,
-    command_template: list[str],
-    files: list[Path],
-    repo_path: Path,
-) -> LinterResult:
-    """
-    Execute a linter on a set of files.
-    Returns LinterResult with violations or error.
-    """
-    # Build command: [linter_bin, args..., files...]
-    # Most linters accept file paths as positional args at the end
-    cmd = [linter_name] if " " not in linter_name else linter_name.split()
-    cmd.extend(command_template[1:])  # Skip the duplicated linter name from template
-
-    # Add file paths, relative to repo root for cleaner output
-    rel_files = [str(f.relative_to(repo_path)) for f in files]
-    cmd.extend(rel_files)
-
-    try:
-        proc = subprocess.run(
-            cmd,
-            cwd=repo_path,
-            capture_output=True,
-            text=True,
-            timeout=60,
-        )
-    except subprocess.TimeoutExpired:
-        return LinterResult(
-            linter_name=linter_name,
-            language="unknown",
-            violations=[],
-            timed_out=True,
-            error="Linter timed out after 60s",
-        )
-    except FileNotFoundError:
-        return LinterResult(
-            linter_name=linter_name,
-            language="unknown",
-            violations=[],
-            error=f"Linter not found: {linter_name}",
-        )
-
-    # Parse output based on linter type
-    violations = parse_linter_output(linter_name, proc.stdout, proc.stderr, repo_path)
-
-    return LinterResult(
-        linter_name=linter_name,
-        language=guess_language_for_linter(linter_name),
-        violations=violations,
-        error=proc.stderr.strip() if proc.returncode != 0 and not violations else None,
-    )
-
-
-def guess_language_for_linter(linter_name: str) -> str:
-    """Map linter name back to language category."""
-    mapping = {
-        "pylint": "python",
-        "ruff": "python",
-        "flake8": "python",
-        "eslint": "javascript",
-        "shellcheck": "shell",
-        "yamllint": "yaml",
-        "jsonlinter": "json",
-        "rubocop": "ruby",
-        "golangci-lint": "go",
-        "cargo clippy": "rust",
-    }
-    return mapping.get(linter_name, "unknown")
-
-
-def parse_linter_output(
-    linter_name: str,
-    stdout: str,
-    stderr: str,
-    repo_path: Path,
-) -> list[Violation]:
-    """
-    Parse linter output into Violation objects.
-    Supports JSON output (pylint, ruff, eslint, shellcheck json1, yamllint parsable).
-    """
-    violations: list[Violation] = []
-
-    if linter_name in ("pylint", "ruff", "eslint"):
-        # JSON array output
-        try:
-            data = json.loads(stdout)
-        except json.JSONDecodeError:
-            return []
-
-        if linter_name == "pylint":
-            for msg in data:
-                violations.append(Violation(
-                    file=msg.get("path", "").lstrip("./"),
-                    line=msg.get("line"),
-                    column=msg.get("column"),
-                    message=msg.get("message", ""),
-                    severity="error" if msg.get("type") == "error" else "warning",
-                    linter=linter_name,
-                    code=msg.get("symbol"),
-                ))
-        elif linter_name == "ruff":
-            for entry in data:
-                violations.append(Violation(
-                    file=entry.get("filename", "").lstrip("./"),
-                    line=entry.get("location", {}).get("row"),
-                    column=entry.get("location", {}).get("column"),
-                    message=entry.get("message", ""),
-                    severity="error",  # ruff treats all as errors
-                    linter=linter_name,
-                    code=entry.get("code"),
-                ))
-        elif linter_name == "eslint":
-            for entry in data:
-                violations.append(Violation(
-                    file=entry.get("fileName", "").lstrip("./"),
-                    line=entry.get("range", {}).get("start", {}).get("line"),
-                    column=entry.get("range", {}).get("start", {}).get("column"),
-                    message=entry.get("message", ""),
-                    severity=entry.get("severity", 1) and "error" or "warning",
-                    linter=linter_name,
-                    code=entry.get("ruleId"),
-                ))
-
-    elif linter_name == "shellcheck":
-        # shellcheck --format=json1
-        try:
-            data = json.loads(stdout)
-            for issue in data.get("issues", []):
-                violations.append(Violation(
-                    file=issue.get("file", "").lstrip("./"),
-                    line=issue.get("line"),
-                    column=issue.get("column"),
-                    message=issue.get("message", ""),
-                    severity="error" if issue.get("level") == "error" else "warning",
-                    linter=linter_name,
-                    code=str(issue.get("code")),
-                ))
-        except json.JSONDecodeError:
-            pass
-
-    elif linter_name == "yamllint":
-        # parsable: file:line:col: level message [rule]
-        # Example: test.yaml:3:1: [error] wrong document start (document-start)
-        for line in stdout.splitlines():
-            parts = line.split(":")
-            if len(parts) >= 4:
-                file_rel = parts[0].lstrip("./")
-                line_num = int(parts[1]) if parts[1].isdigit() else None
-                col_num = int(parts[2]) if parts[2].isdigit() else None
-                rest = ":".join(parts[3:]).strip()
-                # Parse: "[error] message (rule)"
-                import re
-                m = re.match(r'\[(\w+)\]\s+(.+?)(?:\s+\(([^)]+)\))?$', rest)
-                if m:
-                    severity = m.group(1).lower()
-                    message = m.group(2)
-                    code = m.group(3)
-                    violations.append(Violation(
-                        file=file_rel,
-                        line=line_num,
-                        column=col_num,
-                        message=message,
-                        severity=severity,
-                        linter=linter_name,
-                        code=code,
-                    ))
-
-    elif linter_name == "jsonlinter":
-        # json.tool syntax check — no violations, just exit code
-        if proc.returncode != 0:
-            violations.append(Violation(
-                file="(multiple)",
-                line=None,
-                column=None,
-                message="JSON syntax error (run json.tool on each file individually)",
-                severity="error",
-                linter="json.tool",
-            ))
-
-    return violations
-
-
-def run_linters_for_language(
-    language: str,
-    files: list[Path],
-    repo_path: Path,
-) -> LinterResult:
-    """
-    Run the first available linter for this language.
-    Returns the first successful run, or aggregates all errors if none available.
-    """
-    linter_options = LINTERS_BY_LANGUAGE.get(language, [])
-    if not linter_options:
-        return LinterResult(linter_name="none", language=language, violations=[],
-                            error=f"No linter configured for {language}")
-
-    for linter_name, cmd_template in linter_options:
-        # Check if linter exists
-        if not find_linter_executable(linter_name):
-            continue  # Try next linter for this language
-
-        result = run_linter(linter_name, cmd_template, files, repo_path)
-        if not result.error and not result.timed_out:
-            return result
-        # If this linter failed to start (not found), try next
-        if result.error and "not found" in result.error.lower():
-            continue
-
-    # All linters failed
-    errors = []
-    for linter_name, _ in linter_options:
-        if find_linter_executable(linter_name):
-            errors.append(f"{linter_name}: not runnable")
-        else:
-            errors.append(f"{linter_name}: not installed")
-    return LinterResult(
-        linter_name="/".join(l[0] for l in linter_options),
-        language=language,
-        violations=[],
-        error="; ".join(errors),
-    )
-
-
-# ---------------------------------------------------------------------------
-# Main
-# ---------------------------------------------------------------------------
-
-def parse_args():
-    p = argparse.ArgumentParser(description="Linter Runner for compounding-intelligence")
-    p.add_argument("--repo", type=str, help="Path to repository (absolute or relative)")
-    p.add_argument("--all", action="store_true", help="Scan all repos in knowledge/repos/")
-    p.add_argument("--format", choices=["console", "json"], default="console",
-                   help="Output format (default: console)")
-    p.add_argument("--fail-on", choices=["error", "warning", "any"], default="error",
-                   help="Exit non-zero if any violations at this level are found")
-    p.add_argument("--output", type=str, help="Write report to file (default: stdout)")
-    return p.parse_args()
-
-
-def main():
-    args = parse_args()
-
-    if not args.repo and not args.all:
-        print("ERROR: Must specify --repo <path> or --all", file=sys.stderr)
-        sys.exit(2)
-
-    repos_to_scan = []
-    if args.repo:
-        repos_to_scan.append(Path(args.repo).resolve())
-    if args.all:
-        repos_dir = REPO_ROOT / "knowledge" / "repos"
-        if repos_dir.exists():
-            for yaml_file in repos_dir.glob("*.yaml"):
-                # Extract repo name from filename
-                repos_to_scan.append(REPO_ROOT / yaml_file.stem)
-        else:
-            print(f"WARNING: knowledge/repos/ not found, --all has nothing to scan", file=sys.stderr)
-
-    all_results: dict[str, dict] = {}
-    exit_code = 0
-
-    for repo_path in repos_to_scan:
-        if not repo_path.exists():
-            print(f"WARNING: Repo not found: {repo_path}", file=sys.stderr)
-            continue
-
-        repo_name = repo_path.name
-        print(f"\n=== Scanning: {repo_name} ===") if args.format == "console" else None
-
-        lang_files = detect_languages(repo_path)
-        results_by_lang: dict[str, LinterResult] = {}
-
-        for language, files in sorted(lang_files.items()):
-            # Limit files for sanity (first 200 for now)
-            if len(files) > 200:
-                print(f"  {language}: {len(files)} files (limiting to first 200)", file=sys.stderr)
-                files = files[:200]
-
-            result = run_linters_for_language(language, files, repo_path)
-            results_by_lang[language] = result
-
-            if args.format == "console":
-                _print_language_result(language, result, repo_name)
-            else:
-                pass  # JSON aggregation below
-
-        # Build summary
-        total_issues = sum(len(r.violations) for r in results_by_lang.values())
-        total_errors = sum(1 for v in (v for r in results_by_lang.values() for v in r.violations)
-                           if v.severity == "error")
-        total_warnings = sum(1 for v in (v for r in results_by_lang.values() for v in r.violations)
-                             if v.severity == "warning")
-
-        if args.format == "console":
-            print(f"  Summary: {total_issues} issues  ({total_errors} errors, {total_warnings} warnings)")
-        else:
-            all_results[repo_name] = {
-                "languages": {lang: _result_to_dict(res) for lang, res in results_by_lang.items()},
-                "summary": {
-                    "total_issues": total_issues,
-                    "errors": total_errors,
-                    "warnings": total_warnings,
-                },
-            }
-
-        # Determine exit code based on --fail-on
-        if args.fail_on == "error" and total_errors > 0:
-            exit_code = 1
-        elif args.fail_on == "warning" and total_issues > 0:
-            exit_code = 1
-        elif args.fail_on == "any" and total_issues > 0:
-            exit_code = 1
-
-    if args.format == "json":
-        output = json.dumps({"repos": all_results, "meta": {"scanned": len(repos_to_scan)}}, indent=2)
-        if args.output:
-            Path(args.output).write_text(output)
-        else:
-            print(output)
-
-    sys.exit(exit_code)
-
-
-def _print_language_result(language: str, result: LinterResult, repo_name: str):
-    """Pretty-print a single language's lint results."""
-    status = "✓"
-    if result.error:
-        status = "✗"
-        print(f"  {language}: {result.error}")
-    elif result.timed_out:
-        status = "⌛"
-        print(f"  {language}: timed out")
-    else:
-        n_violations = len(result.violations)
-        if n_violations == 0:
-            print(f"  {language}: clean")
-        else:
-            errors = sum(1 for v in result.violations if v.severity == "error")
-            warnings = n_violations - errors
-            print(f"  {language}: {n_violations} issues ({errors} errors, {warnings} warnings)")
-            # Show first 3 violations as preview
-            for v in result.violations[:3]:
-                loc = f"{v.file}:{v.line or '?'}"
-                print(f"    {loc} [{v.severity.upper()}] {v.message[:70]}")
-            if len(result.violations) > 3:
-                print(f"    ... and {len(result.violations) - 3} more")
-
-
-def _result_to_dict(result: LinterResult) -> dict:
-    return {
-        "linter": result.linter_name,
-        "language": result.language,
-        "violations": [asdict(v) for v in result.violations],
-        "timed_out": result.timed_out,
-        "error": result.error,
-    }
-
-
-if __name__ == "__main__":
-    main()

tests/test_linter_runner.py

@@ -1,222 +0,0 @@
-#!/usr/bin/env python3
-"""Tests for linter_runner module (Issue #155).
-
-Tests cover:
-- Language detection by file extension
-- Linter result aggregation
-- Violation parsing (JSON output formats)
-- Exit code logic (fail-on)
-- Report formatting (console/JSON)
-"""
-import json
-import sys
-import tempfile
-from pathlib import Path
-
-import pytest
-
-# Add scripts to path
-sys.path.insert(0, str(Path(__file__).parent.parent / "scripts"))
-
-from linter_runner import (
-    Violation,
-    LinterResult,
-    detect_languages,
-    parse_linter_output,
-    _result_to_dict,
-    EXTENSION_TO_LANGUAGE,
-    LINTERS_BY_LANGUAGE,
-)
-
-
-class TestLanguageDetection:
-    """Test detect_languages() identifies languages correctly."""
-
-    def test_detects_python_files(self, tmp_path: Path):
-        (tmp_path / "main.py").write_text("print('hello')")
-        (tmp_path / "lib" / "utils.py").mkdir(parents=True)
-        (tmp_path / "lib" / "utils.py").write_text("def foo(): pass")
-
-        result = detect_languages(tmp_path)
-        assert "python" in result
-        assert len(result["python"]) == 2
-
-    def test_detects_javascript_files(self, tmp_path: Path):
-        (tmp_path / "app.js").write_text("console.log('hi')")
-        (tmp_path / "component.jsx").write_text("<div/>")
-
-        result = detect_languages(tmp_path)
-        assert "javascript" in result
-        assert len(result["javascript"]) == 2
-
-    def test_detects_shell_files(self, tmp_path: Path):
-        (tmp_path / "setup.sh").write_text("#!/bin/bash\necho hi")
-        (tmp_path / "build.sh").write_text("make")
-
-        result = detect_languages(tmp_path)
-        assert "shell" in result
-        assert len(result["shell"]) == 2
-
-    def test_detects_yaml_files(self, tmp_path: Path):
-        (tmp_path / "config.yml").write_text("key: value")
-        (tmp_path / "env.yaml").write_text("env: test")
-
-        result = detect_languages(tmp_path)
-        assert "yaml" in result
-        assert len(result["yaml"]) == 2
-
-    def test_ignores_git_directory(self, tmp_path: Path):
-        git_dir = tmp_path / ".git"
-        git_dir.mkdir()
-        (git_dir / "config").write_text("placeholder")
-        (tmp_path / "script.py").write_text("print(1)")
-
-        result = detect_languages(tmp_path)
-        assert "python" in result
-        assert not any(".git" in str(f) for f in result.get("python", []))
-
-    def test_returns_empty_for_nonexistent_path(self):
-        result = detect_languages(Path("/nonexistent/path/xyz"))
-        assert result == {}
-
-    def test_mixed_languages(self, tmp_path: Path):
-        (tmp_path / "app.py").write_text("")
-        (tmp_path / "main.js").write_text("")
-        (tmp_path / "deploy.sh").write_text("")
-
-        result = detect_languages(tmp_path)
-        langs = set(result.keys())
-        assert {"python", "javascript", "shell"} <= langs
-
-    def test_limits_files_to_known_languages(self, tmp_path: Path):
-        (tmp_path / "readme.txt").write_text("text")
-        (tmp_path / "data.csv").write_text("a,b,c")
-
-        result = detect_languages(tmp_path)
-        assert len(result) == 0
-
-
-class TestViolationParsing:
-    """Test parse_linter_output parses various linter formats."""
-
-    def test_parses_pylint_json(self):
-        stdout = json.dumps([
-            {"type": "error", "module": "test.py", "line": 10, "column": 5,
-             "message": "Missing docstring", "symbol": "missing-docstring"},
-            {"type": "warning", "module": "test.py", "line": 15, "column": 1,
-             "message": "Line too long", "symbol": "line-too-long"},
-        ])
-        violations = parse_linter_output("pylint", stdout, "", Path("/repo"))
-        assert len(violations) == 2
-        assert violations[0].severity == "error"
-        assert violations[0].message == "Missing docstring"
-        assert violations[1].severity == "warning"
-        assert violations[1].code == "line-too-long"
-
-    def test_parses_ruff_json(self):
-        stdout = json.dumps([
-            {"filename": "src/main.py", "location": {"row": 5, "column": 1},
-             "code": "E501", "message": "Line too long"},
-        ])
-        violations = parse_linter_output("ruff", stdout, "", Path("/repo"))
-        assert len(violations) == 1
-        assert violations[0].file == "src/main.py"
-        assert violations[0].line == 5
-        assert violations[0].code == "E501"
-
-    def test_parses_eslint_json(self):
-        stdout = json.dumps([
-            {"fileName": "app.js", "range": {"start": {"line": 2, "column": 0}},
-             "message": "Unexpected console statement", "severity": 2, "ruleId": "no-console"},
-        ])
-        violations = parse_linter_output("eslint", stdout, "", Path("/repo"))
-        assert len(violations) == 1
-        assert violations[0].severity == "error"
-        assert violations[0].code == "no-console"
-
-    def test_parses_shellcheck_json1(self):
-        stdout = json.dumps({
-            "issues": [
-                {"file": "script.sh", "line": 3, "column": 1,
-                 "message": "Quote this to prevent word splitting", "level": "warning", "code": "SC2086"},
-            ]
-        })
-        violations = parse_linter_output("shellcheck", stdout, "", Path("/repo"))
-        assert len(violations) == 1
-        assert violations[0].severity == "warning"
-        assert violations[0].code == "SC2086"
-
-    def test_parses_yamllint_parsable(self):
-        stdout = "config.yaml:3:1: [error] wrong document start (document-start)\n"
-        violations = parse_linter_output("yamllint", stdout, "", Path("/repo"))
-        assert len(violations) == 1
-        assert violations[0].file == "config.yaml"
-        assert violations[0].line == 3
-        assert violations[0].severity == "error"
-        assert violations[0].code == "document-start"
-
-    def test_returns_empty_on_invalid_json(self):
-        stdout = "Not valid JSON"
-        violations = parse_linter_output("pylint", stdout, "", Path("/repo"))
-        assert violations == []
-
-    def test_strips_leading_slash_from_paths(self):
-        stdout = json.dumps([{"type": "error", "module": "/repo/src/test.py",
-                              "line": 1, "column": 1, "message": "test", "symbol": "T001"}])
-        violations = parse_linter_output("pylint", stdout, "", Path("/repo"))
-        assert violations[0].file == "src/test.py"
-
-
-class TestLinterResult:
-    """Test LinterResult and JSON serialization."""
-
-    def test_result_to_dict_roundtrip(self):
-        v = Violation(file="test.py", line=10, column=5, message="msg",
-                      severity="error", linter="pylint", code="E001")
-        r = LinterResult(linter_name="pylint", language="python", violations=[v])
-        d = _result_to_dict(r)
-        assert d["linter"] == "pylint"
-        assert d["violations"][0]["file"] == "test.py"
-        assert d["violations"][0]["code"] == "E001"
-
-
-class TestIntegration:
-    """End-to-end integration tests with temporary repos."""
-
-    def test_linter_runner_accepts_repo_path(self, tmp_path: Path):
-        (tmp_path / "main.py").write_text("print('hello')")
-        (tmp_path / "bad.py").write_text("import unused_module\nx=1")
-
-        from linter_runner import detect_languages, run_linters_for_language
-
-        langs = detect_languages(tmp_path)
-        assert "python" in langs
-
-        result = run_linters_for_language("python", langs["python"][:1], tmp_path)
-        assert result.language == "python"
-        assert result.violations or result.error  # either linter output or not-installed
-
-    def test_json_output_structure(self, tmp_path: Path):
-        (tmp_path / "script.py").write_text("print(1)")
-
-        from linter_runner import detect_languages, run_linters_for_language, _result_to_dict
-
-        langs = detect_languages(tmp_path)
-        if "python" not in langs:
-            pytest.skip("No Python files detected")
-
-        result = run_linters_for_language("python", langs["python"], tmp_path)
-        report = {
-            "repo": tmp_path.name,
-            "languages": {"python": _result_to_dict(result)},
-            "summary": {
-                "total_issues": len(result.violations),
-                "errors": sum(1 for v in result.violations if v.severity == "error"),
-            },
-        }
-        json.dumps(report)  # should not raise
-
-
-if __name__ == "__main__":
-    print("Run: pytest tests/test_linter_runner.py -v")
-