feat: add <br> inside empty paragraph in rehypeSqueezeParagraphs

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@matters/matters-editor",
-  "version": "0.2.3-alpha.1",
+  "version": "0.2.3-alpha.2",
   "description": "Editor for matters.news",
   "author": "https://github.com/thematters",
   "homepage": "https://github.com/thematters/matters-editor",

src/transformers/lib/index.ts

@@ -0,0 +1 @@
+export * from './rehypeSqueezeParagraphs'

src/transformers/lib/rehypeSqueezeParagraphs.ts

@@ -0,0 +1,74 @@
+import { type Root, type RootContent } from 'hast'
+
+/**
+ * Squeeze empty paragraphs to a maximum of N
+ *
+ * e.g.
+ * <p></p><p></p><p></p><p></p><p></p><p></p>
+ * =>
+ * <p><br></p><p><br></p>
+ *
+ * @param {number} maxCount
+ */
+export const rehypeSqueezeParagraphs =
+  ({ maxCount }: { maxCount: number }) =>
+  (tree: Root) => {
+    if (tree.type !== 'root') {
+      return
+    }
+
+    const children: RootContent[] = []
+    let count = 0
+    let touched = false
+
+    tree.children.forEach((node) => {
+      // skip empty text nodes
+      if (node.type === 'text' && node.value.replace(/\s/g, '') === '') {
+        children.push(node)
+        return
+      }
+
+      // skip non-paragraph nodes
+      if (node.type !== 'element' || node.tagName !== 'p') {
+        count = 0
+        children.push(node)
+        return
+      }
+
+      // skip non-empty paragraphs:
+      // - <p></p>
+      // - <p><br/></p>
+      const isEmptyParagraph =
+        node.children.length === 0 ||
+        node.children.every((n) => n.type === 'element' && n.tagName === 'br')
+      if (!isEmptyParagraph) {
+        count = 0
+        children.push(node)
+        return
+      }
+
+      // cap empty paragraphs
+      count++
+      if (count <= maxCount) {
+        children.push({
+          type: 'element',
+          tagName: 'p',
+          properties: {},
+          children: [
+            {
+              type: 'element',
+              tagName: 'br',
+              properties: {},
+              children: [],
+            },
+          ],
+        })
+      } else {
+        touched = true
+      }
+    })
+
+    if (touched) {
+      tree.children = children
+    }
+  }

src/transformers/normalize-sanitize.test.ts

@@ -0,0 +1,72 @@
+import { stripIndent } from 'common-tags'
+import rehypeFormat from 'rehype-format'
+import rehypeParse from 'rehype-parse'
+import rehypeRaw from 'rehype-raw'
+import rehypeStringify from 'rehype-stringify'
+import { unified } from 'unified'
+import { describe, expect, test } from 'vitest'
+
+import { normalizeArticleHTML } from './normalize'
+import { rehypeParseOptions, rehypeStringifyOptions } from './options'
+import { sanitizeHTML } from './sanitize'
+
+const formatter = unified()
+  .use(rehypeParse, rehypeParseOptions)
+  .use(rehypeRaw)
+  .use(rehypeFormat)
+  .use(rehypeStringify, rehypeStringifyOptions)
+
+const formatHTML = (html: string): string => {
+  const result = formatter.processSync(html)
+  return String(result)
+}
+
+const expectProcessArticleHTML = (input: string, output: string) => {
+  const result = normalizeArticleHTML(sanitizeHTML(input))
+  expect(formatHTML(result).trim()).toBe(output)
+}
+
+// const expectProcessCommentHTML = (input: string, output: string) => {
+//   const result = normalizeCommentHTML(sanitizeHTML(input))
+//   expect(formatHTML(result).trim()).toBe(output)
+// }
+
+describe('Sanitize and normalize article', () => {
+  test('squeeze empty paragraphys', () => {
+    expectProcessArticleHTML(
+      stripIndent`
+        <p>abc</p>
+        <p></p>
+        <p></p>
+        abc
+        <p></p>
+        <p>abc</p>
+        <p></p>
+        <p></p>
+        <p></p>
+        <p>abc</p>
+        <p></p>
+        <p><br></p>
+        <p><br/></p>
+        <p><br></br></p>
+        <p><br/><br/><br/></p>
+        <p></p>
+      `,
+      stripIndent`
+        <p>abc</p>
+        <p><br class="smart"></p>
+        <p><br class="smart"></p>
+        <p>abc</p>
+        <p><br class="smart"></p>
+        <p>abc</p>
+        <p><br class="smart"></p>
+        <p><br class="smart"></p>
+        <p>abc</p>
+        <p><br class="smart"></p>
+        <p><br class="smart"></p>
+      `,
+    )
+  })
+})
+
+// describe('Sanitize and normalize comment', () => {})

src/transformers/normalize.test.ts

@@ -7,7 +7,7 @@ const expectNormalizeArticleHTML = (input: string, output: string) => {
   expect(result.trim()).toBe(output)
 }
 
-export const expectNormalizeCommentHTML = (input: string, output: string) => {
+const expectNormalizeCommentHTML = (input: string, output: string) => {
   const result = normalizeCommentHTML(input)
   expect(result.trim()).toBe(output)
 }

src/transformers/sanitize.test.ts

@@ -1,10 +1,14 @@
 import { stripIndent } from 'common-tags'
 import { describe, expect, test } from 'vitest'
 
-import { sanitizeHTML } from './sanitize'
-
-const expectSanitizeHTML = (input: string, output: string): void => {
-  const result = sanitizeHTML(input)
+import { sanitizeHTML, type SanitizeHTMLOptions } from './sanitize'
+
+const expectSanitizeHTML = (
+  input: string,
+  output: string,
+  options?: SanitizeHTMLOptions,
+): void => {
+  const result = sanitizeHTML(input, options)
   expect(result.trim()).toBe(output)
 }
 
@@ -40,18 +44,51 @@ describe('Sanitization: custom', () => {
         <p><br/><br/><br/></p>
         <p></p>
       `,
+      stripIndent`
+        <p>abc</p>
+        <p><br></p>
+        <p><br></p>abc
+        <p><br></p>
+        <p>abc</p>
+        <p><br></p>
+        <p><br></p>
+        <p>abc</p>
+        <p><br></p>
+        <p><br></p>
+      `,
+    )
+  })
+
+  test('allow max one empty paragraphys', () => {
+    expectSanitizeHTML(
       stripIndent`
         <p>abc</p>
         <p></p>
-        <p></p>abc
+        <p></p>
+        abc
         <p></p>
         <p>abc</p>
         <p></p>
         <p></p>
+        <p></p>
         <p>abc</p>
         <p></p>
+        <p><br></p>
+        <p><br/></p>
+        <p><br></br></p>
+        <p><br/><br/><br/></p>
         <p></p>
       `,
+      stripIndent`
+        <p>abc</p>
+        <p><br></p>abc
+        <p><br></p>
+        <p>abc</p>
+        <p><br></p>
+        <p>abc</p>
+        <p><br></p>
+      `,
+      { maxEmptyParagraphs: 1 },
     )
   })
 })

src/transformers/sanitize.ts

@@ -1,92 +1,33 @@
-import { type Root, type RootContent } from 'hast'
 import rehypeFormat from 'rehype-format'
 import rehypeParse from 'rehype-parse'
 import rehypeRaw from 'rehype-raw'
 import rehypeSanitize from 'rehype-sanitize'
 import rehypeStringify from 'rehype-stringify'
 import { unified } from 'unified'
 
+import { rehypeSqueezeParagraphs } from './lib'
 import {
   rehypeParseOptions,
   rehypeSanitizeOptions,
   rehypeStringifyOptions,
 } from './options'
 
-/**
- * Squeeze empty paragraphs to a maximum of N
- *
- * e.g.
- * <p></p><p></p><p></p><p></p><p></p><p></p>
- * =>
- * <p></p><p></p>
- *
- * @param {number} maxCount
- */
-const rehypeSqueezeParagraphs =
-  ({ maxCount }: { maxCount: number }) =>
-  (tree: Root) => {
-    if (tree.type !== 'root') {
-      return
-    }
-
-    const children: RootContent[] = []
-    let count = 0
-    let touched = false
-
-    tree.children.forEach((node) => {
-      // skip empty text nodes
-      if (node.type === 'text' && node.value.replace(/\s/g, '') === '') {
-        children.push(node)
-        return
-      }
-
-      // skip non-paragraph nodes
-      if (node.type !== 'element' || node.tagName !== 'p') {
-        count = 0
-        children.push(node)
-        return
-      }
-
-      // skip non-empty paragraphs:
-      // - <p></p>
-      // - <p><br/></p>
-      const isEmptyParagraph =
-        node.children.length === 0 ||
-        node.children.every((n) => n.type === 'element' && n.tagName === 'br')
-      if (!isEmptyParagraph) {
-        count = 0
-        children.push(node)
-        return
-      }
-
-      // cap empty paragraphs
-      count++
-      if (count <= maxCount) {
-        children.push({
-          type: 'element',
-          tagName: 'p',
-          properties: {},
-          children: [],
-        })
-      } else {
-        touched = true
-      }
-    })
-
-    if (touched) {
-      tree.children = children
-    }
-  }
+export interface SanitizeHTMLOptions {
+  maxEmptyParagraphs?: number
+}
 
-const formatter = unified()
-  .use(rehypeParse, rehypeParseOptions)
-  .use(rehypeRaw)
-  .use(rehypeSanitize, rehypeSanitizeOptions)
-  .use(rehypeSqueezeParagraphs, { maxCount: 2 })
-  .use(rehypeFormat)
-  .use(rehypeStringify, rehypeStringifyOptions)
+export const sanitizeHTML = (
+  html: string,
+  { maxEmptyParagraphs }: SanitizeHTMLOptions = {},
+): string => {
+  const formatter = unified()
+    .use(rehypeParse, rehypeParseOptions)
+    .use(rehypeRaw)
+    .use(rehypeSanitize, rehypeSanitizeOptions)
+    .use(rehypeSqueezeParagraphs, { maxCount: maxEmptyParagraphs ?? 2 })
+    .use(rehypeFormat)
+    .use(rehypeStringify, rehypeStringifyOptions)
 
-export const sanitizeHTML = (html: string): string => {
   const result = formatter.processSync(html)
   return String(result)
 }