Add "IN" script expression operator

README.md

@@ -85,11 +85,12 @@ Script expressions are not supported as the original author intended because:
 
 So here are the types of query expressions that are supported:
 
-	[?(@._KEY_ _OPERATOR_ _VALUE_)] // <, >, !=, and ==
+	[?(@._KEY_ _OPERATOR_ _VALUE_)] // <, >, !=, == and in
 	Eg.
 	[?(@.title == "A string")] //
 	[?(@.title = "A string")]
 	// A single equals is not an assignment but the SQL-style of '=='
+    [?(@.title in ["A string", "Another string"])]
 
 Similar projects
 ----------------

src/Flow/JSONPath/Filters/QueryMatchFilter.php

@@ -7,7 +7,7 @@ class QueryMatchFilter extends AbstractFilter
 {
     const MATCH_QUERY_OPERATORS = '
     @(\.(?<key>\w+)|\[["\'](?<keySquare>.*?)["\']\])
-    (\s*(?<operator>==|=|>|<)\s*(?<comparisonValue>\S.+))?
+    (\s*(?<operator>==|=|>|<|in)\s*(?<comparisonValue>\S.+))?
     ';
 
     /**
@@ -34,18 +34,27 @@ public function filter($collection)
         $operator = isset($matches['operator']) ? $matches['operator'] : null;
         $comparisonValue   = isset($matches['comparisonValue']) ? $matches['comparisonValue'] : null;
 
-        if (strtolower($comparisonValue) === "false") {
-            $comparisonValue = false;
-        }
-        if (strtolower($comparisonValue) === "true") {
-            $comparisonValue = true;
-        }
-        if (strtolower($comparisonValue) === "null") {
-            $comparisonValue = null;
-        }
+        if (substr($comparisonValue, 0, 1) === "[" && substr($comparisonValue, -1) === "]") {
+            $comparisonValue = substr($comparisonValue, 1, -1);
+            $comparisonValue = preg_replace('/^[\'"]/', '', $comparisonValue);
+            $comparisonValue = preg_replace('/[\'"]$/', '', $comparisonValue);
+            $comparisonValue = preg_replace('/[\'"],[ ]{0,}[\'"]/', ',', $comparisonValue);
+
+            $comparisonValue = explode(",", $comparisonValue);
+        } else {
+            if (strtolower($comparisonValue) === "false") {
+                $comparisonValue = false;
+            }
+            if (strtolower($comparisonValue) === "true") {
+                $comparisonValue = true;
+            }
+            if (strtolower($comparisonValue) === "null") {
+                $comparisonValue = null;
+            }
 
-        $comparisonValue = preg_replace('/^[\'"]/', '', $comparisonValue);
-        $comparisonValue = preg_replace('/[\'"]$/', '', $comparisonValue);
+            $comparisonValue = preg_replace('/^[\'"]/', '', $comparisonValue);
+            $comparisonValue = preg_replace('/[\'"]$/', '', $comparisonValue);
+        }
 
         foreach ($collection as $value) {
             if (AccessHelper::keyExists($value, $key, $this->magicIsAllowed)) {
@@ -67,10 +76,13 @@ public function filter($collection)
                 if ($operator == "<" && $value1 < $comparisonValue) {
                     $return[] = $value;
                 }
+                if ($operator == "in" && in_array($value1, $comparisonValue)) {
+                    $return[] = $value;
+                }
             }
         }
 
         return $return;
     }
 }
-
+

src/Flow/JSONPath/Filters/QueryResultFilter.php

@@ -54,4 +54,4 @@ public function filter($collection)
         return $result;
     }
 }
-
+

tests/JSONPathTest.php

@@ -110,6 +110,18 @@ public function testQueryMatchEquals()
         $this->assertEquals($results[0], 'The Lord of the Rings');
     }
 
+    /**
+     * $..books[?(@.author in ["J. R. R. Tolkien", "Nigel Rees"])]
+     * Filter books that have a title in ["...", "..."]
+     */
+    public function testQueryMatchIn()
+    {
+        $result = (new JSONPath($this->exampleData(rand(0, 1))))->find('$..books[?(@.author in ["J. R. R. Tolkien", "Nigel Rees"])].title');
+        $resultArray = $result->data();
+        $expectedArray = ['The Lord of the Rings', 'Sayings of the Century'];
+        $this->assertEquals(ksort($expectedArray), ksort($resultArray));
+    }
+
     /**
      * $.store.books[*].author
      */