Add tableCellAlignToStyle option

lib/index.js

@@ -95,6 +95,9 @@
  * @property {StylePropertyNameCase | null | undefined} [stylePropertyNameCase='dom']
  *   Specify casing to use for property names in `style` objects (default:
  *   `'dom'`).
+ * @property {boolean | null | undefined} [tableCellAlignToStyle=true]
+ *   Turn obsolete `align` props on `td` and `th` into CSS `style` props
+ *   (default: `true`).
  *
  * @typedef RuntimeDevelopment
  *   Runtime fields when development is on.
@@ -175,6 +178,8 @@
  *   Current schema.
  * @property {StylePropertyNameCase} stylePropertyNameCase
  *   Casing to use for property names in `style` objects.
+ * @property {boolean} tableCellAlignToStyle
+ *   Turn obsolete `align` props on `td` and `th` into CSS `style` props.
  *
  * @typedef {Record<string, string>} Style
  *   Style map.
@@ -229,6 +234,8 @@ const dashSomething = /-([a-z])/g
 // See: <https://github.com/rehypejs/rehype-react/pull/45>.
 const tableElements = new Set(['table', 'tbody', 'thead', 'tfoot', 'tr'])
 
+const tableCellElement = new Set(['td', 'th'])
+
 /**
  * Transform a hast tree to preact, react, solid, svelte, vue, etc.,
  * with an automatic JSX runtime.
@@ -281,7 +288,8 @@ export function toJsxRuntime(tree, options) {
     passKeys: options.passKeys !== false,
     passNode: options.passNode || false,
     schema: options.space === 'svg' ? svg : html,
-    stylePropertyNameCase: options.stylePropertyNameCase || 'dom'
+    stylePropertyNameCase: options.stylePropertyNameCase || 'dom',
+    tableCellAlignToStyle: options.tableCellAlignToStyle !== false
   }
 
   const result = one(state, tree, undefined)
@@ -479,6 +487,9 @@ function createProperties(state, ancestors) {
   let prop
 
   if ('properties' in node && node.properties) {
+    /** @type {string | undefined} */
+    let alignValue
+
     for (prop in node.properties) {
       if (prop !== 'children' && own.call(node.properties, prop)) {
         const result = createProperty(
@@ -489,10 +500,34 @@ function createProperties(state, ancestors) {
         )
 
         if (result) {
-          props[result[0]] = result[1]
+          const [key, value] = result
+
+          if (
+            state.tableCellAlignToStyle &&
+            key === 'align' &&
+            typeof value === 'string' &&
+            tableCellElement.has(node.tagName)
+          ) {
+            alignValue = value
+          } else {
+            props[key] = value
+          }
         }
       }
     }
+
+    if (alignValue) {
+      // Assume style is an object.
+      const style = /** @type {Style} */ (props.style || (props.style = {}))
+      const cssField = 'text-align'
+      style[
+        state.stylePropertyNameCase === 'css'
+          ? // Note: test this when Solid doesn’t want to merge my upcoming PR.
+            /* c8 ignore next */
+            transformStyleToCssCasing(cssField)
+          : cssField
+      ] = alignValue
+    }
   }
 
   return props
@@ -538,7 +573,7 @@ function createProperty(state, ancestors, prop, value) {
         : parseStyle(state, ancestors, String(value))
 
     if (state.stylePropertyNameCase === 'css') {
-      styleObject = transformStyleToCssCasing(styleObject)
+      styleObject = transformStylesToCssCasing(styleObject)
     }
 
     return ['style', styleObject]
@@ -619,24 +654,34 @@ function parseStyle(state, ancestors, value) {
  * @param {Style} domCasing
  * @returns {Style}
  */
-function transformStyleToCssCasing(domCasing) {
+function transformStylesToCssCasing(domCasing) {
   /** @type {Style} */
   const cssCasing = {}
   /** @type {string} */
   let from
 
   for (from in domCasing) {
     if (own.call(domCasing, from)) {
-      let to = from.replace(cap, toDash)
-      // Handle `ms-xxx` -> `-ms-xxx`.
-      if (to.slice(0, 3) === 'ms-') to = '-' + to
-      cssCasing[to] = domCasing[from]
+      cssCasing[transformStyleToCssCasing(from)] = domCasing[from]
     }
   }
 
   return cssCasing
 }
 
+/**
+ * Transform a DOM casing style field to a CSS casing style field.
+ *
+ * @param {string} from
+ * @returns {string}
+ */
+function transformStyleToCssCasing(from) {
+  let to = from.replace(cap, toDash)
+  // Handle `ms-xxx` -> `-ms-xxx`.
+  if (to.slice(0, 3) === 'ms-') to = '-' + to
+  return to
+}
+
 /**
  * Make `$1` capitalized.
  *

package.json

@@ -104,6 +104,7 @@
     "prettier": true,
     "#": "`n` is wrong",
     "rules": {
+      "max-depth": "off",
       "n/file-extension-in-import": "off",
       "unicorn/prefer-at": "off",
       "unicorn/prefer-string-replace-all": "off"

readme.md

@@ -206,6 +206,9 @@ Configuration (TypeScript type).
     ([`StylePropertyNameCase`][api-style-property-name-case],
     default: `'dom'`)
     — specify casing to use for property names in `style` objects
+*   `tableCellAlignToStyle`
+    (`boolean`, default: `true`)
+    — turn obsolete `align` props on `td` and `th` into CSS `style` props
 
 ### `Components`
 

test/index.js

@@ -596,3 +596,60 @@ test('react specific: filter whitespace in tables', async function (t) {
     }
   )
 })
+
+test('react specific: `align` to `style`', async function (t) {
+  const tree = h(null, [
+    h('th', {style: 'color:red', align: 'center'}, 'alpha'),
+    h('td', {style: 'background-color:blue;', align: 'left'}, 'bravo'),
+    h('td', {align: 'right'}, 'charlie'),
+    h('td', 'delta')
+  ])
+
+  await t.test(
+    'should not transform `align` w/ `tableCellAlignToStyle: false`',
+    async function () {
+      assert.equal(
+        renderToStaticMarkup(
+          toJsxRuntime(tree, {...production, tableCellAlignToStyle: false})
+        ),
+        '<th style="color:red" align="center">alpha</th><td style="background-color:blue" align="left">bravo</td><td align="right">charlie</td><td>delta</td>'
+      )
+    }
+  )
+
+  await t.test(
+    'should transform `align` w/o `tableCellAlignToStyle`',
+    async function () {
+      assert.equal(
+        renderToStaticMarkup(toJsxRuntime(tree, production)),
+        '<th style="color:red;text-align:center">alpha</th><td style="background-color:blue;text-align:left">bravo</td><td style="text-align:right">charlie</td><td>delta</td>'
+      )
+    }
+  )
+
+  await t.test(
+    "should suppoort `tableCellAlignToStyle` w/ `stylePropertyNameCase: 'css'`",
+    async function () {
+      /** @type {unknown} */
+      let foundProps
+
+      assert.equal(
+        renderToStaticMarkup(
+          toJsxRuntime(h('td', {align: 'center'}), {
+            ...production,
+            jsx(type, props) {
+              foundProps = props
+              return production.jsx(type, {})
+            },
+            stylePropertyNameCase: 'css'
+          })
+        ),
+        '<td></td>'
+      )
+
+      assert.deepEqual(foundProps, {
+        style: {'text-align': 'center'}
+      })
+    }
+  )
+})