Logging adapter that stores log entries in the StateChart for testing.

This adapter is designed for use in test environments where you want to:

• Keep test output clean (no log pollution)
• Inspect log messages in tests
• Verify that correct logging occurs

The adapter stores log entries in the StateChart's logs field as a list, with optional circular buffer behavior to prevent memory growth.

Configuration

# Unlimited log storage
adapter = %Statifier.Logging.TestAdapter{}

# Circular buffer with max 100 entries
adapter = %Statifier.Logging.TestAdapter{max_entries: 100}

Log Entry Format

Each log entry is a map with the following structure:

%{
  timestamp: ~U[2023-01-01 12:00:00.000000Z],
  level: :info,
  message: "Processing started",
  metadata: %{action_type: "initialization"}
}

Usage in Tests

# Create state chart with TestAdapter
{:ok, state_chart} = Interpreter.initialize(document, [
  log_adapter: {Statifier.Logging.TestAdapter, [max_entries: 50]}
])

# ... perform actions that log ...

# Inspect captured logs
assert [%{level: :info, message: "Processing started"}] = state_chart.logs