Forms: Fix forms source warning (#45501)

* Forms: fix source php warning

* changelog

* Check that the source is larger then 0.

* use absint and wp_unslash

* fix typo

* minor

* fix

Author: enejb

projects/packages/forms/changelog/fix-forms-source-warning

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fixed
+
+Forms: fix PHP warning for when a site doesn't have the JWT token yet

projects/packages/forms/src/contact-form/class-contact-form.php

@@ -256,9 +256,25 @@ public static function get_instance_from_jwt( $jwt_token ) {
 		} catch ( \Exception $e ) {
 			return null;
 		}
+		$source = $data['source'] ?? array();
+		if ( empty( $source ) ) {
+			// phpcs:ignore WordPress.Security.NonceVerification.Missing -- check done by caller process_form_submission()
+			$source_post_id = ! empty( $_POST['contact-form-id'] ) && is_numeric( $_POST['contact-form-id'] ) ? absint( wp_unslash( $_POST['contact-form-id'] ) ) : 0;
+			$post           = get_post( $source_post_id );
+			if ( $post !== null && $source_post_id > 0 ) {
+				// create a fallback source
+				$source = array(
+					'source_id'   => $post->ID,
+					'entry_title' => $post->post_title,
+					'entry_page'  => 1,
+					'source_type' => 'single',
+					'request_url' => get_permalink( $post ),
+				);
+			}
+		}
 
 		$form                   = new self( $data['attributes'], $data['content'], empty( $data['attributes']['id'] ) );
-		$form->source           = Feedback_Source::from_serialized( $data['source'] );
+		$form->source           = Feedback_Source::from_serialized( $source );
 		$form->hash             = $data['hash'];
 		$form->has_verified_jwt = true;
 		return $form;

projects/plugins/jetpack/changelog/fix-forms-source-warning

@@ -0,0 +1,5 @@
+Significance: patch
+Type: bugfix
+Comment: This change has not been deployed to jetpack sites yet
+
+