src/Composer/Json/JsonFile.php
public function write(array $hash, $options = 448)
    {
        $dir = dirname($this->path);
        if (!is_dir($dir)) {
            if (file_exists($dir)) {
                throw new \UnexpectedValueException(
                    $dir.' exists and is not a directory.'
                );
            }
            if (!@mkdir($dir, 0777, true)) {
                throw new \UnexpectedValueException(
                    $dir.' does not exist and could not be created.'
                );
            }
        }

        $retries = 3;
        while ($retries--) {
            try {
                file_put_contents($this->path, static::encode($hash, $options). ($options & self::JSON_PRETTY_PRINT ? "\n" : ''));
                break;
            } catch (\Exception $e) {
                if ($retries) {
                    usleep(500000);
                    continue;
                }

                throw $e;
            }
        }
    }
public function write(array $hash, $options = 448)
    {
        $dir = dirname($this->path);
        if (!is_dir($dir)) {
            if (file_exists($dir)) {
                throw new \UnexpectedValueException(
                    $dir.' exists and is not a directory.'
                );
            }
            if (!@mkdir($dir, 0777, true)) {
                throw new \UnexpectedValueException(
                    $dir.' does not exist and could not be created.'
                );
            }
        }

        $retries = 3;
        while ($retries--) {
            try {
                file_put_contents($this->path, static::encode($hash, $options). ($options & self::JSON_PRETTY_PRINT ? "\n" : ''));
                break;
            } catch (\Exception $e) {
                if ($retries) {
                    usleep(500000);
                    continue;
                }

                throw $e;
            }
        }
    }
Writes json file.

@param  array                                $hash    writes hash into json file
@param  int                                  $options json_encode options (defaults to JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE)
@throws \UnexpectedValueException|\Exception