[Data Liberation] Anomaly Testing

[zaerl]

SQLite has a relatively strict anomaly testing that we should ensure is covered in the Data Liberation plugin.

Out-Of-Memory Testing

• Test with default memory limit (128 MB). Alert the user if the value is lower before importing.
• Randomly set ini_set('memory_limit', '_a_small_one_M'); to simulate an OOM in one of the WP_Stream_Importer::next_step() and see if the system can recover.

I/O Error Testing

• Simulate errors for copy() and other FS functions or use WP_Filesystem_Direct as a base for the plugin and create a testing class that generates errors at random.
• Test rogue files such as zip bomb

Crash Testing

• Trigger a fatal error like calling non_existent_function(); in the middle of an import and try to restart it from that point.

Compound failure tests

• Stack 2, 3, 4 of the above errors in the same test run.