Test program output against solution file

test.py

@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+
+import argparse
+import subprocess
+from pathlib import Path
+
+RESET = "\033[0m"
+GRAY = "\033[1;90m"
+GREEN = "\033[1;32m"
+MAGENTA = "\033[1;35m"
+RED = "\033[1;31m"
+
+
+def find_solutions(paths):
+    pairs = {}
+    for path in paths:
+        if path.suffix == ".input":
+            pairs[path] = path.parent / (path.stem + ".solution")
+    return pairs
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("file", type=Path, nargs="+")
+    parser.add_argument("--command", "-c", required=True, action="append")
+    parser.add_argument("--diff", "-d", default="diff")
+    args = parser.parse_args()
+
+    for inputpath, solutionpath in sorted(find_solutions(args.file).items()):
+        try:
+            with open(solutionpath) as f:
+                solutionstr = f.read()
+        except FileNotFoundError:
+            print(f"{GRAY}No solution{RESET} for {inputpath}")
+            continue
+
+        resultstr = subprocess.run(
+            args.command + [inputpath], check=True, capture_output=True, text=True
+        ).stdout
+
+        if resultstr.strip() == solutionstr.strip():
+            print(f"{GREEN}Passed{RESET} {inputpath}")
+        elif resultstr.strip() == "":
+            print(f"{MAGENTA}No answer{RESET} for {inputpath}")
+        else:
+            print(f"{RED}Failed{RESET} {inputpath}")
+            subprocess.run([args.diff, solutionpath, "-"], input=resultstr, text=True)
+
+
+if __name__ == "__main__":
+    main()