Issue #2853823 by Jo Fitzgerald, claudiu.cristea, Munavijayalakshmi, phenaproxima, alexpott, heddn: Explode processor is too strict regarding to the input value

core/modules/migrate/src/Plugin/migrate/process/Explode.php

@@ -22,6 +22,11 @@ use Drupal\migrate\Row;
  *     returned.
  *   - If the limit parameter is zero, then this is treated as 1.
  * - delimiter: The boundary string.
+ * - strict: (optional) When this boolean is TRUE, the source should be strictly
+ *   a string. If FALSE is passed, the source value is casted to a string before
+ *   being split. Also, in this case, the values casting to empty strings are
+ *   converted to empty arrays, instead of an array with a single empty string
+ *   item ['']. Defaults to TRUE.
  *
  * Example:
  *
@@ -29,8 +34,8 @@ use Drupal\migrate\Row;
  * process:
  *   bar:
  *     plugin: explode
- *       source: foo
- *       delimiter: /
+ *     source: foo
+ *     delimiter: /
  * @endcode
  *
  * If foo is "node/1", then bar will be ['node', '1']. The PHP equivalent of
@@ -44,9 +49,9 @@ use Drupal\migrate\Row;
  * process:
  *   bar:
  *     plugin: explode
- *       source: foo
- *       limit: 1
- *       delimiter: /
+ *     source: foo
+ *     limit: 1
+ *     delimiter: /
  * @endcode
  *
  * If foo is "node/1/edit", then bar will be ['node', '1/edit']. The PHP
@@ -56,6 +61,30 @@ use Drupal\migrate\Row;
  *   $bar = explode('/', $foo, 1);
  * @endcode
  *
+ * If the 'strict' configuration is set to FALSE, the input value is casted to a
+ * string before being spilt:
+ *
+ * @code
+ * process:
+ *   bar:
+ *     plugin: explode
+ *     source: foo
+ *     delimiter: /
+ *     strict: false
+ * @endcode
+ *
+ * If foo is 123 (as integer), then bar will be ['123']. If foo is TRUE, then
+ * bar will be ['1']. The PHP equivalent of this would be:
+ *
+ * @code
+ *   $bar = explode('/', (string) 123);
+ *   $bar = explode('/', (string) TRUE);
+ * @endcode
+ *
+ * If the 'strict' configuration is set to FALSE, the source value casting to
+ * an empty string are converted to an empty array. For example, with the last
+ * configuration, if foo is '', NULL or FALSE, then bar will be [].
+ *
  * @see \Drupal\migrate\Plugin\MigrateProcessInterface
  *
  * @MigrateProcessPlugin(
@@ -68,18 +97,29 @@ class Explode extends ProcessPluginBase {
    * {@inheritdoc}
    */
   public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
-    if (is_string($value)) {
-      if (!empty($this->configuration['delimiter'])) {
-        $limit = isset($this->configuration['limit']) ? $this->configuration['limit'] : PHP_INT_MAX;
-        return explode($this->configuration['delimiter'], $value, $limit);
-      }
-      else {
-        throw new MigrateException('delimiter is empty');
-      }
+    if (empty($this->configuration['delimiter'])) {
+      throw new MigrateException('delimiter is empty');
     }
-    else {
+
+    $strict = array_key_exists('strict', $this->configuration) ? $this->configuration['strict'] : TRUE;
+    if ($strict && !is_string($value)) {
       throw new MigrateException(sprintf('%s is not a string', var_export($value, TRUE)));
     }
+    elseif (!$strict) {
+      // Check if the incoming value can cast to a string.
+      $original = $value;
+      if (!is_string($original) && ($original != ($value = @strval($value)))) {
+        throw new MigrateException(sprintf('%s cannot be casted to a string', var_export($original, TRUE)));
+      }
+      // Empty strings should be exploded to empty arrays.
+      if ($value === '') {
+        return [];
+      }
+    }
+
+    $limit = isset($this->configuration['limit']) ? $this->configuration['limit'] : PHP_INT_MAX;
+
+    return explode($this->configuration['delimiter'], $value, $limit);
   }
 
   /**

core/modules/migrate/tests/src/Unit/process/ExplodeTest.php

@@ -2,6 +2,7 @@
 
 namespace Drupal\Tests\migrate\Unit\process;
 
+use Drupal\migrate\MigrateException;
 use Drupal\migrate\Plugin\migrate\process\Explode;
 use Drupal\migrate\Plugin\migrate\process\Concat;
 
@@ -53,23 +54,65 @@ class ExplodeTest extends MigrateProcessTestCase {
 
   /**
    * Test explode fails properly on non-strings.
-   *
-   * @expectedException \Drupal\migrate\MigrateException
-   *
-   * @expectedExceptionMessage is not a string
    */
   public function testExplodeWithNonString() {
+    $this->setExpectedException(MigrateException::class, 'is not a string');
     $this->plugin->transform(['foo'], $this->migrateExecutable, $this->row, 'destinationproperty');
   }
 
+  /**
+   * Tests that explode works on non-strings but with strict set to FALSE.
+   *
+   * @dataProvider providerExplodeWithNonStrictAndEmptySource
+   */
+  public function testExplodeWithNonStrictAndEmptySource($value, $expected) {
+    $plugin = new Explode(['delimiter' => '|', 'strict' => FALSE], 'map', []);
+
+    $processed = $plugin->transform($value, $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertSame($expected, $processed);
+  }
+
+  /**
+   * Data provider for ::testExplodeWithNonStrictAndEmptySource().
+   */
+  public function providerExplodeWithNonStrictAndEmptySource() {
+    return [
+      'normal_string' => ['a|b|c', ['a', 'b', 'c']],
+      'integer_cast_to_string' => [123, ['123']],
+      'zero_integer_cast_to_string' => [0, ['0']],
+      'true_cast_to_string' => [TRUE, ['1']],
+      'null_empty_array' => [NULL, []],
+      'false_empty_array' => [FALSE, []],
+      'empty_string_empty_array' => ['', []],
+    ];
+  }
+
+  /**
+   * Tests that explode raises an exception when the value cannot be casted to
+   * string.
+   */
+  public function testExplodeWithNonStrictAndNonCastable() {
+    $plugin = new Explode(['delimiter' => '|', 'strict' => FALSE], 'map', []);
+    $this->setExpectedException(MigrateException::class, 'cannot be casted to a string');
+    $processed = $plugin->transform(['foo'], $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertSame(['foo'], $processed);
+  }
+
+  /**
+   * Tests that explode with an empty string and strict check returns a
+   * non-empty array.
+   */
+  public function testExplodeWithStrictAndEmptyString() {
+    $plugin = new Explode(['delimiter' => '|'], 'map', []);
+    $processed = $plugin->transform('', $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertSame([''], $processed);
+  }
+
   /**
    * Test explode fails with empty delimiter.
-   *
-   * @expectedException \Drupal\migrate\MigrateException
-   *
-   * @expectedExceptionMessage delimiter is empty
    */
   public function testExplodeWithEmptyDelimiter() {
+    $this->setExpectedException(MigrateException::class, 'delimiter is empty');
     $plugin = new Explode(['delimiter' => ''], 'map', []);
     $plugin->transform('foo,bar', $this->migrateExecutable, $this->row, 'destinationproperty');
   }