S005 Edge Cases
| ID | Scenario | Expected Behavior |
|---|---|---|
| S005-EC-001 | Plugin directory (.parity/plugins/ or ~/.parity/plugins/) does not exist | loadDirectory() MUST return immediately without producing any warning. is_dir() check prevents glob on non-existent path. |
| S005-EC-002 | Plugin file returns a non-RuleInterface object (e.g., return new stdClass()) | The loader MUST record a warning: "Plugin {file} did not return a RuleInterface or array of rules". No rule is registered from this file. |
| S005-EC-003 | Plugin file throws any \Throwable during require (syntax error, exception in top-level code) | The loader MUST catch the \Throwable and record a warning: "Plugin {file} failed to load: {message}". Loading continues with the next file. |
| S005-EC-004 | Plugin file returns an empty array (return []) | No rules are registered. No warning is produced (an empty array is a valid return value per S005-FR-006.b -- iteration simply yields no items). |
| S005-EC-005 | Plugin file returns an array containing a mix of RuleInterface instances and non-conforming values (e.g., [new ValidRule(), 'garbage', null, new AnotherValidRule()]) | The loader MUST register the RuleInterface instances (ValidRule, AnotherValidRule) and silently skip non-conforming elements ('garbage', null). No warning is produced for the skipped elements. |
| S005-EC-006 | Composer package declares a class that exists but does not implement RuleInterface | The loader MUST record a warning: "Composer plugin {package}: {class} does not implement RuleInterface". The class is not registered. |
| S005-EC-007 | Composer package declares a class that does not exist (not autoloadable) | The loader MUST record a warning: "Composer plugin {package}: class {class} not found". The check uses class_exists() before instantiation. |
| S005-EC-008 | vendor/composer/installed.json contains malformed JSON (parse error) | json_decode() returns null, which fails the is_array() check. The loader MUST silently return without processing any packages or producing a warning. |
| S005-EC-009 | vendor/composer/installed.json does not exist (no Composer dependencies, or vendor/ missing) | is_file() check returns false. The loader MUST silently return. No warning produced. |
| S005-EC-010 | HOME environment variable is unset or empty (all three sources: $_SERVER['HOME'], $_ENV['HOME'], getenv('HOME') fail) | The global-user plugin location MUST be skipped entirely. No warning produced. Project-local and Composer discovery proceed normally. |
| S005-EC-011 | A plugin registers a rule with the same name as a built-in rule (e.g., "test-exists") | The plugin's rule replaces the built-in in the registry (last-write-wins per S005-FR-009). No warning produced. All subsequent references to that name resolve to the plugin's implementation. |
| S005-EC-012 | Plugin directory contains files with non-.php extensions (e.g., .txt, .md, .bak) | The glob('*.php') pattern MUST exclude non-PHP files. They are never loaded and no warning is produced. |
| S005-EC-013 | Composer extra.parity.rules contains a non-string entry (e.g., integer, array, null) | The is_string($className) check MUST fail, and the loader MUST record a warning: "Composer plugin {package}: class {value} not found". Processing continues with the next entry. |
| S005-EC-014 | Plugin file returns null explicitly (return null) | null is neither a RuleInterface instance nor an array. The loader MUST record a warning: "Plugin {file} did not return a RuleInterface or array of rules". |
| S005-EC-015 | Composer package has extra.parity.rules set to an empty array ([]) | The foreach loop iterates zero times. No rules registered, no warnings produced. Package is silently skipped. |