Bug/4391 make markdown auto wrapping optional

docs/syntax/flowchart.md

@@ -828,6 +828,11 @@ Formatting:
 
 This feature is applicable to node labels, edge labels, and subgraph labels.
 
+The auto wrapping can be disabled by using
+
+    %%{init: {"markdownAutoWrap": false} }%%
+    graph LR
+
 ## Interaction
 
 It is possible to bind a click event to a node, the click can lead to either a javascript callback or to a link which will be opened in a new browser tab.

packages/mermaid/src/config.type.ts

@@ -158,6 +158,7 @@ export interface MermaidConfig {
   dompurifyConfig?: DOMPurifyConfiguration;
   wrap?: boolean;
   fontSize?: number;
+  markdownAutoWrap?: boolean;
 }
 /**
  * This interface was referenced by `MermaidConfig`'s JSON-Schema

packages/mermaid/src/docs/syntax/flowchart.md

@@ -519,6 +519,13 @@ Formatting:
 
 This feature is applicable to node labels, edge labels, and subgraph labels.
 
+The auto wrapping can be disabled by using
+
+```
+%%{init: {"markdownAutoWrap": false} }%%
+graph LR
+```
+
 ## Interaction
 
 It is possible to bind a click event to a node, the click can lead to either a javascript callback or to a link which will be opened in a new browser tab.

packages/mermaid/src/rendering-util/createText.ts

@@ -169,9 +169,9 @@ export const createText = (
   log.info('createText', text, style, isTitle, classes, useHtmlLabels, isNode, addSvgBackground);
   if (useHtmlLabels) {
     // TODO: addHtmlLabel accepts a labelStyle. Do we possibly have that?
-    // text = text.replace(/\\n|\n/g, '<br />');
+
     const htmlText = markdownToHTML(text);
-    // log.info('markdo  wnToHTML' + text, markdownToHTML(text));
+
     const node = {
       isNode,
       label: decodeEntities(htmlText).replace(

packages/mermaid/src/rendering-util/handle-markdown-text.spec.ts

@@ -1,5 +1,6 @@
 import { markdownToLines, markdownToHTML } from './handle-markdown-text.js';
 import { test, expect } from 'vitest';
+import { setConfig } from '../config.js';
 
 test('markdownToLines - Basic test', () => {
   const input = `This is regular text
@@ -262,3 +263,11 @@ test('markdownToHTML - Unsupported formatting', () => {
   - l3`)
   ).toMatchInlineSnapshot('"<p>Hello</p>Unsupported markdown: list"');
 });
+
+test('markdownToHTML - no auto wrapping', () => {
+  setConfig({ markdownAutoWrap: false });
+  expect(
+    markdownToHTML(`Hello, how do
+  you do?`)
+  ).toMatchInlineSnapshot('"<p>Hello,&nbsp;how&nbsp;do<br/>you&nbsp;do?</p>"');
+});

packages/mermaid/src/rendering-util/handle-markdown-text.ts

@@ -2,16 +2,21 @@
 import { fromMarkdown } from 'mdast-util-from-markdown';
 import { dedent } from 'ts-dedent';
 import type { MarkdownLine, MarkdownWordType } from './types.js';
+import { getConfig } from '../config.js';
 
 /**
  * @param markdown - markdown to process
  * @returns processed markdown
  */
 function preprocessMarkdown(markdown: string): string {
+  const markdownAutoWrap = getConfig().markdownAutoWrap;
   // Replace multiple newlines with a single newline
   const withoutMultipleNewlines = markdown.replace(/\n{2,}/g, '\n');
   // Remove extra spaces at the beginning of each line
   const withoutExtraSpaces = dedent(withoutMultipleNewlines);
+  if (markdownAutoWrap === false) {
+    return withoutExtraSpaces.replace(/ /g, ' ');
+  }
   return withoutExtraSpaces;
 }
 
@@ -58,10 +63,15 @@
 
 export function markdownToHTML(markdown: string) {
   const { children } = fromMarkdown(markdown);
+  const markdownAutoWrap = getConfig().markdownAutoWrap;
 
   function output(node: Content): string {
     if (node.type === 'text') {
-      return node.value.replace(/\n/g, '<br/>');
+      if (markdownAutoWrap === false) {
+        return node.value.replace(/\n/g, '<br/>').replace(/ /g, '&nbsp;');
+      } else {
+        return node.value.replace(/\n/g, '<br/>');
+      }
     } else if (node.type === 'strong') {
       return `<strong>${node.children.map(output).join('')}</strong>`;
     } else if (node.type === 'emphasis') {

packages/mermaid/src/schemas/config.schema.yaml

@@ -217,6 +217,8 @@ properties:
   fontSize:
     type: number
     default: 16
+  markdownAutoWrap:
+    type: boolean
 
 $defs: # JSON Schema definition (maybe we should move these to a seperate file)
   BaseDiagramConfig: