From cd6f8e5a245ec14dbe5dc265af05254d7fa0062e Mon Sep 17 00:00:00 2001
From: darshanr0107 <darshan@mermaidchart.com>
Date: Mon, 21 Jul 2025 18:41:18 +0530
Subject: [PATCH] tidy-tree as the default layout for mindmaps

on-behalf-of: @Mermaid-Chart <hello@mermaidchart.com>
---
 packages/mermaid/src/preprocess.ts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/packages/mermaid/src/preprocess.ts b/packages/mermaid/src/preprocess.ts
index a62326070..7e3a50b8b 100644
--- a/packages/mermaid/src/preprocess.ts
+++ b/packages/mermaid/src/preprocess.ts
@@ -1,4 +1,5 @@
 import { cleanupComments } from './diagram-api/comments.js';
+import { detectType } from './diagram-api/detectType.js';
 import { extractFrontMatter } from './diagram-api/frontmatter.js';
 import type { DiagramMetadata } from './diagram-api/types.js';
 import utils, { cleanAndMerge, removeDirectives } from './utils.js';
@@ -18,6 +19,7 @@ const cleanupText = (code: string) => {
 
 const processFrontmatter = (code: string) => {
   const { text, metadata } = extractFrontMatter(code);
+  const diagramType = detectType(text);
   const { displayMode, title, config = {} } = metadata;
   if (displayMode) {
     // Needs to be supported for legacy reasons
@@ -26,6 +28,9 @@ const processFrontmatter = (code: string) => {
     }
     config.gantt.displayMode = displayMode;
   }
+  if (diagramType === 'mindmap' && !config.layout) {
+    config.layout = 'tidy-tree';
+  }
   return { title, config, text };
 };