fix: check post_content before parsing it for blocks (#211)

* chore: stub WP_Post_Type and boostrap main plugin file during phpstan

* fix: check for `$post->post_content` before parsing for blocks

.changeset/quick-maps-exercise.md

@@ -0,0 +1,5 @@
+---
+"@wpengine/wp-graphql-content-blocks": patch
+---
+
+fix: check for `post_content` before attempting to parse them.

includes/Data/ContentBlocksResolver.php

@@ -58,7 +58,9 @@ public static function resolve_content_blocks( $node, $args, $allowed_block_name
 		$new_parsed_blocks = [];
 		foreach ( $parsed_blocks as $block ) {
 			if ( 'core/block' === $block['blockName'] && $block['attrs']['ref'] ) {
-				$reusable_blocks = parse_blocks( get_post( $block['attrs']['ref'] )->post_content );
+				$post            = get_post( $block['attrs']['ref'] );
+				$reusable_blocks = ! empty( $post->post_content ) ? parse_blocks( $post->post_content ) : null;
+
 				if ( ! empty( $reusable_blocks ) ) {
 					array_push( $new_parsed_blocks, ...$reusable_blocks );
 				}

phpstan-baseline.neon

@@ -30,11 +30,6 @@ parameters:
 			count: 1
 			path: includes/Blocks/Block.php
 
-		-
-			message: "#^Cannot access property \\$post_content on WP_Post\\|null\\.$#"
-			count: 1
-			path: includes/Data/ContentBlocksResolver.php
-
 		-
 			message: "#^Variable \\$block_spec in isset\\(\\) always exists and is not nullable\\.$#"
 			count: 1