last update before handover

sample_interface/node_modules/mdast-util-mdx-expression/lib/index.js

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+/**
+ * @import {CompileContext, Extension as FromMarkdownExtension, Handle as FromMarkdownHandle} from 'mdast-util-from-markdown'
+ * @import {MdxFlowExpression, MdxTextExpression} from 'mdast-util-mdx-expression'
+ * @import {Handle as ToMarkdownHandle, Options as ToMarkdownExtension, State} from 'mdast-util-to-markdown'
+ * @import {Parents} from 'mdast'
+ */
+
+import {ok as assert} from 'devlop'
+
+/**
+ * Create an extension for `mdast-util-from-markdown` to enable MDX expressions
+ * in markdown.
+ *
+ * When using the micromark syntax extension with `addResult`, nodes will have
+ * a `data.estree` field set to an ESTree `Program` node.
+ *
+ * @returns {FromMarkdownExtension}
+ *   Extension for `mdast-util-from-markdown` to enable MDX expressions.
+ */
+export function mdxExpressionFromMarkdown() {
+  return {
+    enter: {
+      mdxFlowExpression: enterMdxFlowExpression,
+      mdxTextExpression: enterMdxTextExpression
+    },
+    exit: {
+      mdxFlowExpression: exitMdxExpression,
+      mdxFlowExpressionChunk: exitMdxExpressionData,
+      mdxTextExpression: exitMdxExpression,
+      mdxTextExpressionChunk: exitMdxExpressionData
+    }
+  }
+}
+
+/**
+ * Create an extension for `mdast-util-to-markdown` to enable MDX expressions
+ * in markdown.
+ *
+ * @returns {ToMarkdownExtension}
+ *   Extension for `mdast-util-to-markdown` to enable MDX expressions.
+ */
+export function mdxExpressionToMarkdown() {
+  return {
+    handlers: {
+      mdxFlowExpression: handleMdxExpression,
+      mdxTextExpression: handleMdxExpression
+    },
+    unsafe: [
+      {character: '{', inConstruct: ['phrasing']},
+      {atBreak: true, character: '{'}
+    ]
+  }
+}
+
+/**
+ * @this {CompileContext}
+ * @type {FromMarkdownHandle}
+ */
+function enterMdxFlowExpression(token) {
+  this.enter({type: 'mdxFlowExpression', value: ''}, token)
+  this.buffer()
+}
+
+/**
+ * @this {CompileContext}
+ * @type {FromMarkdownHandle}
+ */
+function enterMdxTextExpression(token) {
+  this.enter({type: 'mdxTextExpression', value: ''}, token)
+  this.buffer()
+}
+
+/**
+ * @this {CompileContext}
+ * @type {FromMarkdownHandle}
+ */
+function exitMdxExpression(token) {
+  const value = this.resume()
+  const estree = token.estree
+  const node = this.stack[this.stack.length - 1]
+  assert(node.type === 'mdxFlowExpression' || node.type === 'mdxTextExpression')
+  this.exit(token)
+  node.value = value
+
+  if (estree) {
+    node.data = {estree}
+  }
+}
+
+/**
+ * @this {CompileContext}
+ * @type {FromMarkdownHandle}
+ */
+function exitMdxExpressionData(token) {
+  this.config.enter.data.call(this, token)
+  this.config.exit.data.call(this, token)
+}
+
+/**
+ * @type {ToMarkdownHandle}
+ * @param {MdxFlowExpression | MdxTextExpression} node
+ *   Node.
+ * @param {Parents | undefined} parent
+ *   Parent, if any.
+ * @param {State} state
+ *   Info passed around about the current state.
+ * @returns {string}
+ *   Serialized markdown.
+ */
+function handleMdxExpression(node, parent, state) {
+  const value = node.value || ''
+  const result = state.indentLines(value, function (line, index, blank) {
+    // Tab-size to eat has to be the same as what we serialize as.
+    // While in some places in markdown that’s 4, in JS it’s more common as 2.
+    // Which is what’s also in `mdast-util-mdx-jsx`:
+    // <https://github.com/syntax-tree/mdast-util-mdx-jsx/blob/40b951b/lib/index.js#L52>
+    return (index === 0 || blank ? '' : '  ') + line
+  })
+  return '{' + result + '}'
+}