LowFile-scopePHP Plug & play

Add default cases to match expressions

Every match expression must define a default arm that handles unsupported or unexpected values.

Why this matters

Prevents UnhandledMatchError and makes behavior explicit for future enum/constant additions.

Side-by-side examples engineers can pattern-match during review.

Avoid

$out = match($type) { 'a' => 1, 'b' => 2 };

Prefer

$out = match($type) {
    'a' => 1,
    'b' => 2,
    default => throw new InvalidArgumentException("Unsupported type: {$type}")
};

Bad

match($x){ 'a'=>1 }

Good

match($x){ 'a'=>1, default=>0 }

From the same buckets as this rule.

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Avoid equality operators in loop termination conditions
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Critical
Avoid Returning Null in Non-Async Task Methods
Returning null from a Task or Task<T> method causes a NullReferenceException if awaited. Use Task.CompletedTask or Task.FromResult<T>(null) instead.
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Critical
Avoid Using Boolean Expressions in `except` Statements
Detect `except` clauses that use `or` or `and` to catch multiple exceptions. This does not work as intended. Recommend using a tuple of exceptions instead.
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