Hands-On: Multi-Tool Analysis Comparison

"""Run multiple static analysis tools; merge and compare results."""
import subprocess
import json
import xml.etree.ElementTree as ET
from collections import defaultdict

SOURCE_FILES = ["src/SpeedController.c", "src/FaultManager.c"]

def run_cppcheck() -> list:
    """Run cppcheck MISRA analysis; return violation list."""
    result = subprocess.run(
        ["cppcheck", "--addon=misra", "--xml",
         "--output-file=/tmp/cppcheck.xml"] + SOURCE_FILES,
        capture_output=True
    )
    tree = ET.parse("/tmp/cppcheck.xml")
    violations = []
    for error in tree.getroot().iter("error"):
        for loc in error.iter("location"):
            violations.append({
                "tool": "cppcheck",
                "rule": error.get("id"),
                "file": loc.get("file"),
                "line": int(loc.get("line", 0)),
                "msg":  error.get("msg")
            })
    return violations

def deduplicate(all_violations: list) -> dict:
    """Group by (file, line) to find unique vs overlapping findings."""
    by_location = defaultdict(list)
    for v in all_violations:
        key = f"{v['file']}:{v['line']}"
        by_location[key].append(v["tool"])
    unique = {k: v for k, v in by_location.items() if len(set(v)) == 1}
    shared = {k: v for k, v in by_location.items() if len(set(v)) > 1}
    return {"unique": unique, "shared": shared}

violations = run_cppcheck()  # + run_polyspace() etc.
report = deduplicate(violations)
print(f"Total locations with findings: {len(report['unique']) + len(report['shared'])}")
print(f"  Unique to one tool:  {len(report['unique'])}")
print(f"  Shared (>1 tool):    {len(report['shared'])}")