feat: add estree-util-attach-comments

syntax-tree/estree-util-attach-comments#2
unifiedjs/unified#121
sindresorhus/meta#15
https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

package.json

@@ -19,6 +19,7 @@
     "doctrine": "3.0.0",
     "eslint": "7.18.0",
     "espree": "^4",
+    "estree-util-attach-comments": "^2.0.0",
     "fs-extra": "9.1.0",
     "lodash": "4.17.20"
   },

vendor/Readme.md

@@ -0,0 +1,13 @@
+We cannot use Pure ESM packages (e.g. `estree-util-attach-comments`) because:
+
+- Node doesn't support mixing `require` and `import`.
+- Some people are shipping pure ESM without properly fixing Node.
+
+This means we should regress to the old days of `vendor` folders.
+
+See these for more information:
+
+https://github.com/wooorm/estree-util-attach-comments/issues/2
+https://github.com/unifiedjs/unified/issues/121
+https://github.com/sindresorhus/meta/discussions/15
+https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

vendor/estree-util-attach-comments.js

@@ -0,0 +1,150 @@
+"use strict"
+
+exports.__esModule = true
+exports.attachComments = attachComments
+var push = [].push
+/**
+ * @typedef {import('estree').BaseNode} EstreeNode
+ * @typedef {import('estree').Comment} EstreeComment
+ *
+ * @typedef State
+ * @property {EstreeComment[]} comments
+ * @property {number} index
+ *
+ * @typedef Fields
+ * @property {boolean} leading
+ * @property {boolean} trailing
+ */
+
+/**
+ * Attach semistandard estree comment nodes to the tree.
+ *
+ * @param {EstreeNode} tree
+ * @param {EstreeComment[]} [comments]
+ */
+
+function attachComments(tree, comments) {
+  var list = (comments || []).concat().sort(compare)
+  if (list.length)
+    walk(tree, {
+      comments: list,
+      index: 0,
+    })
+  return tree
+}
+/**
+ * Attach semistandard estree comment nodes to the tree.
+ *
+ * @param {EstreeNode} node
+ * @param {State} state
+ */
+
+function walk(node, state) {
+  /** @type {EstreeNode[]} */
+  var children = []
+  /** @type {EstreeComment[]} */
+
+  var comments = []
+  /** @type {string} */
+
+  var key
+  /** @type {EstreeNode|EstreeNode[]} */
+
+  var value
+  /** @type {number} */
+
+  var index // Done, we can quit.
+
+  if (state.index === state.comments.length) {
+    return
+  } // Find all children of `node`
+
+  for (key in node) {
+    value = node[key] // Ignore comments.
+
+    if (value && typeof value === "object" && key !== "comments") {
+      if (Array.isArray(value)) {
+        index = -1
+
+        while (++index < value.length) {
+          if (value[index] && typeof value[index].type === "string") {
+            children.push(value[index])
+          }
+        }
+      } else if (typeof value.type === "string") {
+        children.push(value)
+      }
+    }
+  } // Sort the children.
+
+  children.sort(compare) // Initial comments.
+
+  push.apply(
+    comments,
+    slice(state, node, false, {
+      leading: true,
+      trailing: false,
+    })
+  )
+  index = -1
+
+  while (++index < children.length) {
+    walk(children[index], state)
+  } // Dangling or trailing comments.
+
+  push.apply(
+    comments,
+    slice(state, node, true, {
+      leading: false,
+      trailing: Boolean(children.length),
+    })
+  )
+
+  if (comments.length) {
+    // @ts-ignore, yes, because they’re nonstandard.
+    node.comments = comments
+  }
+}
+/**
+ * @param {State} state
+ * @param {EstreeNode} node
+ * @param {boolean} compareEnd
+ * @param {Fields} fields
+ */
+
+function slice(state, node, compareEnd, fields) {
+  /** @type {EstreeComment[]} */
+  var result = []
+
+  while (state.comments[state.index] && compare(state.comments[state.index], node, compareEnd) < 1) {
+    result.push(Object.assign({}, state.comments[state.index++], fields))
+  }
+
+  return result
+}
+/**
+ * @param {EstreeNode|EstreeComment} left
+ * @param {EstreeNode|EstreeComment} right
+ * @param {boolean} [compareEnd]
+ * @returns {number}
+ */
+
+function compare(left, right, compareEnd) {
+  var field = compareEnd ? "end" : "start" // Offsets.
+
+  if (left.range && right.range) {
+    return left.range[0] - right.range[compareEnd ? 1 : 0]
+  } // Points.
+
+  if (left.loc && left.loc.start && right.loc && right.loc[field]) {
+    return left.loc.start.line - right.loc[field].line || left.loc.start.column - right.loc[field].column
+  } // Just `start` (and `end`) on nodes.
+  // Default in most parsers.
+
+  if ("start" in left && field in right) {
+    // @ts-ignore Added by Acorn
+    return left.start - right[field]
+  }
+
+  return NaN
+}