# Common Test Utilities
Shared infrastructure for E2E tests.
## DaemonTestHarness
Manages bridge lifecycle for test suites requiring Ghidra bridge interaction.
### Usage
```rust
use common::{DaemonTestHarness, ensure_test_project};
const TEST_PROJECT: &str = "my-test";
const TEST_PROGRAM: &str = "sample_binary";
#[test]
#[serial]
fn test_with_bridge() {
ensure_test_project(TEST_PROJECT, TEST_PROGRAM);
let harness = DaemonTestHarness::new(TEST_PROJECT, TEST_PROGRAM)
.expect("Failed to start bridge");
Command::cargo_bin("ghidra")
.unwrap()
.arg("--project")
.arg(TEST_PROJECT)
.arg("my-command")
.arg("--program")
.arg(TEST_PROGRAM)
.assert()
.success();
// Bridge automatically shuts down when harness drops
}
```
### Port File Discovery
Each harness discovers the bridge via port file:
```
~/.local/share/ghidra-cli/bridge-{md5_hash}.port
```
Where `{md5_hash}` is derived from the canonical project path. The harness reads the port number from this file and connects via TCP.
### Cleanup Guarantees
Drop implementation ensures best-effort cleanup:
1. Send shutdown command via TCP (ignores errors)
2. Bridge deletes its own port/PID files on clean shutdown
3. Kill process via PID if still running
## Fixtures
### fixture_binary()
Returns path to compiled sample_binary fixture.
```rust
let binary = fixture_binary();
assert!(binary.exists());
```
Binary must be compiled before tests:
```bash
rustc --edition 2021 -o tests/fixtures/sample_binary tests/fixtures/sample_binary.rs
```
### ensure_test_project()
Idempotent project setup using `Once::call_once`. Imports and analyzes sample_binary if needed.
```rust
ensure_test_project("my-project", "sample_binary");
// Second call does nothing - project already exists
```
Handles "already exists" errors gracefully. Safe to call from multiple tests.
## require_ghidra! Macro
Tests should call this macro to assert Ghidra availability up front:
```rust
#[test]
fn test_something() {
require_ghidra!();
// Test code runs only if ghidra doctor succeeds
}
```
Runs `ghidra doctor` and fails the test if Ghidra is unavailable, including doctor output.
## GhidraCommand Builder (helpers.rs)
Fluent builder for constructing CLI commands in tests:
```rust
use common::helpers::{ghidra, GhidraCommand};
let result = ghidra(&harness)
.arg("function")
.arg("list")
.run();
result.assert_success();
```
The `ghidra(&harness)` helper pre-configures `--project` args from the harness. Additional helpers include `with_project()`, `json_format()`, and `timeout()`.
## Design Decisions
### Exponential Backoff Parameters
`wait_for_port()` uses backoff to wait for the bridge port file to appear after launching `analyzeHeadless`. Typical fast start exits in <5s.
### Why 5s Shutdown Timeout
Most bridges shut down in <1s. 5s allows graceful cleanup without blocking tests indefinitely. If bridge hangs, hard kill via PID prevents test suite deadlock.