"""
Unit tests for the allow-temp-dirs.py PreToolUse hook.
This hook auto-approves mkdir commands that create directories within temp/,
but must reject any commands with security risks like multiple paths,
shell operators, or command substitution.
"""
import json
import subprocess
import sys
from pathlib import Path
import pytest
HOOK_PATH = Path(__file__).parent.parent / "allow-temp-dirs.py"
def run_hook(command: str, env: dict | None = None) -> dict | None:
"""
Run the hook with a given Bash command and return the parsed output.
Returns None if the hook produces no output (allowing normal permission flow).
Args:
command: The Bash command to test
env: Optional environment variables to pass to the hook
"""
hook_input = {
"tool_input": {
"command": command,
}
}
# Merge with current environment if custom env provided
run_env = None
if env:
import os
run_env = os.environ.copy()
run_env.update(env)
result = subprocess.run(
[sys.executable, str(HOOK_PATH)],
input=json.dumps(hook_input),
capture_output=True,
text=True,
check=False,
env=run_env,
)
if result.stdout.strip():
return json.loads(result.stdout)
return None
def test_hook_exists():
"""Verify the hook file exists and is executable."""
assert HOOK_PATH.exists(), f"Hook not found at {HOOK_PATH}"
class TestValidCommands:
"""Test cases for commands that should be auto-approved."""
def test_simple_temp_mkdir(self):
"""Should approve: mkdir temp/subdir"""
output = run_hook("mkdir temp/subdir")
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_mkdir_with_p_flag(self):
"""Should approve: mkdir -p temp/nested/subdir"""
output = run_hook("mkdir -p temp/nested/subdir")
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_mkdir_with_dot_prefix(self):
"""Should approve: mkdir -p ./temp/subdir"""
output = run_hook("mkdir -p ./temp/subdir")
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_mkdir_with_mode_flag(self):
"""Should approve: mkdir -m 755 temp/subdir"""
output = run_hook("mkdir -m 755 temp/subdir")
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_mkdir_with_multiple_flags(self):
"""Should approve: mkdir -p -m 755 temp/subdir"""
output = run_hook("mkdir -p -m 755 temp/subdir")
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
class TestSecurityRejections:
"""Test cases for commands that should be rejected for security reasons."""
def test_reject_multiple_paths(self):
"""Should reject: mkdir temp/ok /etc"""
output = run_hook("mkdir temp/ok /etc")
assert output is None, "Hook should not approve commands with multiple paths"
def test_reject_multiple_paths_with_flag(self):
"""Should reject: mkdir -p temp/ok /etc"""
output = run_hook("mkdir -p temp/ok /etc")
assert output is None, "Hook should not approve commands with multiple paths"
def test_reject_and_operator(self):
"""Should reject: mkdir temp/ok && mkdir /etc"""
output = run_hook("mkdir temp/ok && mkdir /etc")
assert output is None, "Hook should not approve commands with && operator"
def test_reject_or_operator(self):
"""Should reject: mkdir temp/ok || mkdir /etc"""
output = run_hook("mkdir temp/ok || mkdir /etc")
assert output is None, "Hook should not approve commands with || operator"
def test_reject_semicolon_separator(self):
"""Should reject: mkdir temp/ok; mkdir /etc"""
output = run_hook("mkdir temp/ok; mkdir /etc")
assert output is None, "Hook should not approve commands with ; separator"
def test_reject_pipe_operator(self):
"""Should reject: mkdir temp/ok | tee /etc/evil"""
output = run_hook("mkdir temp/ok | tee /etc/evil")
assert output is None, "Hook should not approve commands with | operator"
def test_reject_command_substitution_dollar(self):
"""Should reject: mkdir temp/$(malicious)"""
output = run_hook("mkdir temp/$(malicious)")
assert output is None, "Hook should not approve commands with $() substitution"
def test_reject_command_substitution_backtick(self):
"""Should reject: mkdir temp/`malicious`"""
output = run_hook("mkdir temp/`malicious`")
assert output is None, "Hook should not approve commands with backtick substitution"
def test_reject_output_redirection(self):
"""Should reject: mkdir temp/ok > /etc/evil"""
output = run_hook("mkdir temp/ok > /etc/evil")
assert output is None, "Hook should not approve commands with output redirection"
def test_reject_input_redirection(self):
"""Should reject: mkdir temp/ok < /etc/passwd"""
output = run_hook("mkdir temp/ok < /etc/passwd")
assert output is None, "Hook should not approve commands with input redirection"
def test_reject_variable_expansion(self):
"""Should reject: mkdir temp/$EVIL"""
output = run_hook("mkdir temp/$EVIL")
assert output is None, "Hook should not approve commands with variable expansion"
def test_reject_brace_expansion(self):
"""Should reject: mkdir temp/{ok,/etc}"""
output = run_hook("mkdir temp/{ok,/etc}")
assert output is None, "Hook should not approve commands with brace expansion"
class TestPathTraversalAndAbsolutePaths:
"""Test cases for path traversal and absolute path security scenarios."""
def test_reject_path_traversal_to_other_project(self):
"""Should reject: mkdir ../other-project/temp/data"""
output = run_hook("mkdir ../other-project/temp/data")
assert output is None, "Hook should not approve path traversal to other directories"
def test_reject_path_traversal_with_flag(self):
"""Should reject: mkdir -p ../other-project/temp/data"""
output = run_hook("mkdir -p ../other-project/temp/data")
assert output is None, "Hook should not approve path traversal even with -p flag"
def test_reject_absolute_path_with_temp_in_middle(self):
"""Should reject: mkdir /etc/malicious/temp/subdir (outside project)"""
output = run_hook("mkdir /etc/malicious/temp/subdir")
assert output is None, "Hook should not approve absolute paths outside project"
def test_reject_absolute_path_with_temp_and_flag(self):
"""Should reject: mkdir -p /var/log/temp/data (outside project)"""
output = run_hook("mkdir -p /var/log/temp/data")
assert output is None, "Hook should not approve absolute paths outside project"
def test_reject_parent_references_escaping_temp(self):
"""Should reject: mkdir temp/../../../etc/shadow"""
output = run_hook("mkdir temp/../../../etc/shadow")
assert output is None, "Hook should not approve paths with parent references escaping temp"
def test_reject_parent_references_with_flag(self):
"""Should reject: mkdir -p temp/../../../../../../etc/passwd"""
output = run_hook("mkdir -p temp/../../../../../../etc/passwd")
assert output is None, "Hook should not approve parent references even with -p flag"
def test_reject_complex_parent_traversal(self):
"""Should reject: mkdir ./temp/../../../usr/local/bin"""
output = run_hook("mkdir ./temp/../../../usr/local/bin")
assert output is None, "Hook should not approve complex parent directory traversal"
class TestAbsolutePathsWithProjectDir:
"""Test cases for absolute paths within CLAUDE_PROJECT_DIR."""
def test_approve_absolute_path_in_project_temp(self):
"""Should approve: mkdir /workspaces/project/temp/subdir with matching CLAUDE_PROJECT_DIR"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir /workspaces/project/temp/subdir", env=env)
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_approve_absolute_path_with_p_flag(self):
"""Should approve: mkdir -p /workspaces/project/temp/nested/dir"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir -p /workspaces/project/temp/nested/dir", env=env)
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_approve_absolute_path_deeply_nested(self):
"""Should approve: mkdir -p /home/user/myproject/temp/a/b/c"""
env = {"CLAUDE_PROJECT_DIR": "/home/user/myproject"}
output = run_hook("mkdir -p /home/user/myproject/temp/a/b/c", env=env)
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_reject_absolute_path_outside_project(self):
"""Should reject: mkdir /other/project/temp/subdir (different project)"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir /other/project/temp/subdir", env=env)
assert output is None, "Hook should not approve paths outside project directory"
def test_reject_absolute_path_no_project_dir_set(self):
"""Should reject: mkdir /workspaces/project/temp/subdir without CLAUDE_PROJECT_DIR"""
# Don't set CLAUDE_PROJECT_DIR - hook should reject all absolute paths
output = run_hook("mkdir /workspaces/project/temp/subdir", env={})
assert output is None, "Hook should reject absolute paths when CLAUDE_PROJECT_DIR not set"
def test_reject_absolute_path_not_in_temp(self):
"""Should reject: mkdir /workspaces/project/src/newdir (not in temp/)"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir /workspaces/project/src/newdir", env=env)
assert output is None, "Hook should not approve paths outside temp/ directory"
def test_reject_absolute_path_with_traversal(self):
"""Should reject: mkdir /workspaces/project/temp/../../../etc"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir /workspaces/project/temp/../../../etc", env=env)
assert output is None, "Hook should reject paths with traversal even within project"
def test_project_dir_with_trailing_slash(self):
"""Should approve with trailing slash in CLAUDE_PROJECT_DIR"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project/"}
output = run_hook("mkdir /workspaces/project/temp/subdir", env=env)
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
def test_approve_absolute_with_mode_flag(self):
"""Should approve: mkdir -m 755 /workspaces/project/temp/subdir"""
env = {"CLAUDE_PROJECT_DIR": "/workspaces/project"}
output = run_hook("mkdir -m 755 /workspaces/project/temp/subdir", env=env)
assert output is not None
assert output["hookSpecificOutput"]["permissionDecision"] == "allow"
class TestNonTempCommands:
"""Test cases for commands that don't target temp/ directory."""
def test_ignore_non_temp_mkdir(self):
"""Should not approve: mkdir /etc/evil"""
output = run_hook("mkdir /etc/evil")
assert output is None, "Hook should not approve non-temp directories"
def test_ignore_home_mkdir(self):
"""Should not approve: mkdir ~/somedir"""
output = run_hook("mkdir ~/somedir")
assert output is None, "Hook should not approve home directory paths"
def test_ignore_relative_non_temp(self):
"""Should not approve: mkdir src/newdir"""
output = run_hook("mkdir src/newdir")
assert output is None, "Hook should not approve non-temp relative paths"
class TestNonMkdirCommands:
"""Test cases for non-mkdir commands."""
def test_ignore_ls_command(self):
"""Should not approve: ls temp/"""
output = run_hook("ls temp/")
assert output is None, "Hook should only handle mkdir commands"
def test_ignore_rm_command(self):
"""Should not approve: rm -rf temp/"""
output = run_hook("rm -rf temp/")
assert output is None, "Hook should only handle mkdir commands"
def test_ignore_empty_command(self):
"""Should not approve: empty string"""
output = run_hook("")
assert output is None, "Hook should handle empty commands gracefully"
if __name__ == "__main__":
pytest.main([__file__, "-v"])
