/usr/share/php/JmesPath/TreeInterpreter.php is in php-jmespath 2.3.0-2ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 | <?php
namespace JmesPath;
/**
* Tree visitor used to evaluates JMESPath AST expressions.
*/
class TreeInterpreter
{
/** @var callable */
private $fnDispatcher;
/**
* @param callable $fnDispatcher Function dispatching function that accepts
* a function name argument and an array of
* function arguments and returns the result.
*/
public function __construct(callable $fnDispatcher = null)
{
$this->fnDispatcher = $fnDispatcher ?: FnDispatcher::getInstance();
}
/**
* Visits each node in a JMESPath AST and returns the evaluated result.
*
* @param array $node JMESPath AST node
* @param mixed $data Data to evaluate
*
* @return mixed
*/
public function visit(array $node, $data)
{
return $this->dispatch($node, $data);
}
/**
* Recursively traverses an AST using depth-first, pre-order traversal.
* The evaluation logic for each node type is embedded into a large switch
* statement to avoid the cost of "double dispatch".
* @return mixed
*/
private function dispatch(array $node, $value)
{
$dispatcher = $this->fnDispatcher;
switch ($node['type']) {
case 'field':
if (is_array($value) || $value instanceof \ArrayAccess) {
return isset($value[$node['value']]) ? $value[$node['value']] : null;
} elseif ($value instanceof \stdClass) {
return isset($value->{$node['value']}) ? $value->{$node['value']} : null;
}
return null;
case 'subexpression':
return $this->dispatch(
$node['children'][1],
$this->dispatch($node['children'][0], $value)
);
case 'index':
if (!Utils::isArray($value)) {
return null;
}
$idx = $node['value'] >= 0
? $node['value']
: $node['value'] + count($value);
return isset($value[$idx]) ? $value[$idx] : null;
case 'projection':
$left = $this->dispatch($node['children'][0], $value);
switch ($node['from']) {
case 'object':
if (!Utils::isObject($left)) {
return null;
}
break;
case 'array':
if (!Utils::isArray($left)) {
return null;
}
break;
default:
if (!is_array($left) || !($left instanceof \stdClass)) {
return null;
}
}
$collected = [];
foreach ((array) $left as $val) {
$result = $this->dispatch($node['children'][1], $val);
if ($result !== null) {
$collected[] = $result;
}
}
return $collected;
case 'flatten':
static $skipElement = [];
$value = $this->dispatch($node['children'][0], $value);
if (!Utils::isArray($value)) {
return null;
}
$merged = [];
foreach ($value as $values) {
// Only merge up arrays lists and not hashes
if (is_array($values) && isset($values[0])) {
$merged = array_merge($merged, $values);
} elseif ($values !== $skipElement) {
$merged[] = $values;
}
}
return $merged;
case 'literal':
return $node['value'];
case 'current':
return $value;
case 'or':
$result = $this->dispatch($node['children'][0], $value);
return Utils::isTruthy($result)
? $result
: $this->dispatch($node['children'][1], $value);
case 'and':
$result = $this->dispatch($node['children'][0], $value);
return Utils::isTruthy($result)
? $this->dispatch($node['children'][1], $value)
: $result;
case 'not':
return !Utils::isTruthy(
$this->dispatch($node['children'][0], $value)
);
case 'pipe':
return $this->dispatch(
$node['children'][1],
$this->dispatch($node['children'][0], $value)
);
case 'multi_select_list':
if ($value === null) {
return null;
}
$collected = [];
foreach ($node['children'] as $node) {
$collected[] = $this->dispatch($node, $value);
}
return $collected;
case 'multi_select_hash':
if ($value === null) {
return null;
}
$collected = [];
foreach ($node['children'] as $node) {
$collected[$node['value']] = $this->dispatch(
$node['children'][0],
$value
);
}
return $collected;
case 'comparator':
$left = $this->dispatch($node['children'][0], $value);
$right = $this->dispatch($node['children'][1], $value);
if ($node['value'] == '==') {
return Utils::isEqual($left, $right);
} elseif ($node['value'] == '!=') {
return !Utils::isEqual($left, $right);
} else {
return self::relativeCmp($left, $right, $node['value']);
}
case 'condition':
return Utils::isTruthy($this->dispatch($node['children'][0], $value))
? $this->dispatch($node['children'][1], $value)
: null;
case 'function':
$args = [];
foreach ($node['children'] as $arg) {
$args[] = $this->dispatch($arg, $value);
}
return $dispatcher($node['value'], $args);
case 'slice':
return is_string($value) || Utils::isArray($value)
? Utils::slice(
$value,
$node['value'][0],
$node['value'][1],
$node['value'][2]
) : null;
case 'expref':
$apply = $node['children'][0];
return function ($value) use ($apply) {
return $this->visit($apply, $value);
};
default:
throw new \RuntimeException("Unknown node type: {$node['type']}");
}
}
/**
* @return bool
*/
private static function relativeCmp($left, $right, $cmp)
{
if (!is_int($left) || !is_int($right)) {
return false;
}
switch ($cmp) {
case '>': return $left > $right;
case '>=': return $left >= $right;
case '<': return $left < $right;
case '<=': return $left <= $right;
default: throw new \RuntimeException("Invalid comparison: $cmp");
}
}
}
|