Add includeImageAlt option

syntax-tree · Apr 26, 2021 · bc43530 · bc43530
1 parent 1b5d8b3
commit bc43530
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Showing 3 changed files with 35 additions and 8 deletions.
diff --git a/index.js b/index.js
@@ -1,37 +1,54 @@
+/**
+ * @typedef Options
+ * @property {boolean} [includeImageAlt=true]
+ */
+
 /**
  * Get the text content of a node.
  * Prefer the node’s plain-text fields, otherwise serialize its children,
  * and if the given value is an array, serialize the nodes in it.
  *
  * @param {unknown} node
+ * @param {Options} [options]
+ * @returns {string}
+ */
+export function toString(node, options) {
+  var {includeImageAlt = true} = options || {}
+  return one(node, includeImageAlt)
+}
+
+/**
+ * @param {unknown} node
+ * @param {boolean} includeImageAlt
  * @returns {string}
  */
-export function toString(node) {
+function one(node, includeImageAlt) {
   return (
     (node &&
       typeof node === 'object' &&
       // @ts-ignore looks like a literal.
       (node.value ||
         // @ts-ignore looks like an image.
-        node.alt ||
+        (includeImageAlt ? node.alt : '') ||
         // @ts-ignore looks like a parent.
-        ('children' in node && all(node.children)) ||
-        (Array.isArray(node) && all(node)))) ||
+        ('children' in node && all(node.children, includeImageAlt)) ||
+        (Array.isArray(node) && all(node, includeImageAlt)))) ||
     ''
   )
 }
 
 /**
  * @param {Array.<unknown>} values
+ * @param {boolean} includeImageAlt
  * @returns {string}
  */
-function all(values) {
+function all(values, includeImageAlt) {
   /** @type {Array.<string>} */
   var result = []
   var index = -1
 
   while (++index < values.length) {
-    result[index] = toString(values[index])
+    result[index] = one(values[index], includeImageAlt)
   }
 
   return result.join('')

diff --git a/readme.md b/readme.md
@@ -40,17 +40,21 @@ console.log(toString(tree)) // => 'Some emphasis, importance, and code.'
 This package exports the following identifiers: `toString`.
 There is no default export.
 
-### `toString(node)`
+### `toString(node[, options])`
 
 Get the text content of a [node][] or list of nodes.
 
-The algorithm checks `value` of `node`, then `alt`, and finally `title`.
+The algorithm checks `value` of `node` and then `alt`.
 If no value is found, the algorithm checks the children of `node` and joins them
 (without spaces or newlines).
 
 > This is not a markdown to plain-text library.
 > Use [`strip-markdown`][strip-markdown] for that.
 
+###### `options.includeImageAlt`
+
+Whether to use `alt` (`boolean`, default: `true`)
+
 ## Security
 
 Use of `mdast-util-to-string` does not involve **[hast][]**, user content, or

diff --git a/test.js b/test.js
@@ -30,6 +30,12 @@ test('toString', function (t) {
     'should *not* prefer `title` over all others'
   )
 
+  t.equal(
+    toString({alt: 'bar'}, {includeImageAlt: false}),
+    '',
+    'should *not* include `alt` w/ `includeImageAlt: false`'
+  )
+
   t.equal(
     toString({children: [{value: 'foo'}, {alt: 'bar'}, {title: 'baz'}]}),
     'foobar',