Replaces traditional array() syntax with the short syntax []

short-array-syntax-converter.php

#!/usr/bin/env php
<?php

/**
 * Converts all PHP files in a directory to short array syntax.
 * Note that this will overwrite all converted PHP files.
 * Be sure to have a backup just in case.
 */

if ($argc !== 2) {
    printf('Usage: %s src-dir' . PHP_EOL, $argv[0]);
    exit(1);
}

$dir = $argv[1];
$files = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($dir));

foreach ($files as $file) {
    /** @var SplFileInfo $file */
    if ($file->isFile()) {
        if (pathinfo($file->getFilename(), PATHINFO_EXTENSION) === 'php') {
            $original = file_get_contents($file->getPathname());
            $modified = convertToShortArraySyntax($original);

            if ($modified !== $original) {
                echo "Converted {$file->getPathname()}\n";
                file_put_contents($file->getPathname(), $modified);
            }
        }
    }
}

function convertToShortArraySyntax(string $php): string
{
    $tokens = token_get_all($php);

    $output = '';
    $bracketStack = [];
    $replaceNextParentheses = false;

    for ($i = 0; isset($tokens[$i]); $i++) {
        $token = $tokens[$i];

        if (is_array($token)) {
            if ($token[0] == T_ARRAY) {
                for ($j = $i + 1; isset($tokens[$j]); $j++) {
                    $peekToken = $tokens[$j];

                    if (is_array($peekToken)) {
                        if ($peekToken[0] == T_WHITESPACE) {
                            continue;
                        }
                        if ($peekToken[1] == '(') {
                            $replaceNextParentheses = true;
                            continue 2;
                        }
                    }
                    elseif ($peekToken == '(') {
                        $replaceNextParentheses = true;
                        continue 2;
                    }

                    break;
                }
            }

            $output .= $token[1];
        } else {
            if ($token == '(') {
                $openingBracket = $replaceNextParentheses ? '[' : '(';
                $closingBracket = $replaceNextParentheses ? ']' : ')';

                $output .= $openingBracket;
                array_push($bracketStack, $closingBracket);
                $replaceNextParentheses = false;
            }
            elseif ($token == ')') {
                $output .= array_pop($bracketStack);
            } else {
                $output .= $token;
            }
        }
    }

    return $output;
}

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