From 2c5d83fab3c7e0472ac9f6e51c4ece21a445af4d Mon Sep 17 00:00:00 2001
From: rhysd <lin90162@yahoo.co.jp>
Date: Sun, 30 Apr 2023 00:32:40 +0900
Subject: [PATCH] Add `suppressErrorRendering` option to avoid inserting
 'Syntax error' message in diagram

---
 packages/mermaid/src/config.type.ts   | 1 +
 packages/mermaid/src/defaultConfig.ts | 8 ++++++++
 packages/mermaid/src/mermaidAPI.ts    | 5 ++++-
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/packages/mermaid/src/config.type.ts b/packages/mermaid/src/config.type.ts
index 545fdbbfb..207ca60d8 100644
--- a/packages/mermaid/src/config.type.ts
+++ b/packages/mermaid/src/config.type.ts
@@ -34,6 +34,7 @@ export interface MermaidConfig {
   dompurifyConfig?: DOMPurify.Config;
   wrap?: boolean;
   fontSize?: number;
+  suppressErrorRendering?: boolean;
 }
 
 // TODO: More configs needs to be moved in here
diff --git a/packages/mermaid/src/defaultConfig.ts b/packages/mermaid/src/defaultConfig.ts
index 9c6d6f46e..00c054358 100644
--- a/packages/mermaid/src/defaultConfig.ts
+++ b/packages/mermaid/src/defaultConfig.ts
@@ -152,6 +152,14 @@ const config: Partial<MermaidConfig> = {
    */
   deterministicIDSeed: undefined,
 
+  /**
+   * This option suppresses inserting 'Syntax error' message in diagram. This option is useful when
+   * you want to control how to handle syntax error in your application.
+   *
+   * Default value: false
+   */
+  suppressErrorRendering: false,
+
   /** The object containing configurations specific for flowcharts */
   flowchart: {
     /**
diff --git a/packages/mermaid/src/mermaidAPI.ts b/packages/mermaid/src/mermaidAPI.ts
index 5e9d0ead6..b31378ce6 100644
--- a/packages/mermaid/src/mermaidAPI.ts
+++ b/packages/mermaid/src/mermaidAPI.ts
@@ -511,7 +511,9 @@ const render = async function (
   try {
     await diag.renderer.draw(text, id, version, diag);
   } catch (e) {
-    errorRenderer.draw(text, id, version);
+    if (!config.suppressErrorRendering) {
+      errorRenderer.draw(text, id, version);
+    }
     throw e;
   }
 
@@ -617,6 +619,7 @@ function addA11yInfo(
  *     securityLevel: 'strict',
  *     startOnLoad: true,
  *     arrowMarkerAbsolute: false,
+ *     suppressErrorRendering: false,
  *
  *     er: {
  *       diagramPadding: 20,