planning

node_modules/mdast-util-to-markdown/lib/util/association.js

@@ -0,0 +1,30 @@
+module.exports = association
+
+var decode = require('parse-entities/decode-entity')
+
+var characterEscape = /\\([!-/:-@[-`{-~])/g
+var characterReference = /&(#(\d{1,7}|x[\da-f]{1,6})|[\da-z]{1,31});/gi
+
+// The `label` of an association is the string value: character escapes and
+// references work, and casing is intact.
+// The `identifier` is used to match one association to another: controversially,
+// character escapes and references don’t work in this matching: `©` does
+// not match `©`, and `\+` does not match `+`.
+// But casing is ignored (and whitespace) is trimmed and collapsed: ` A\nb`
+// matches `a b`.
+// So, we do prefer the label when figuring out how we’re going to serialize:
+// it has whitespace, casing, and we can ignore most useless character escapes
+// and all character references.
+function association(node) {
+  if (node.label || !node.identifier) {
+    return node.label || ''
+  }
+
+  return node.identifier
+    .replace(characterEscape, '$1')
+    .replace(characterReference, decodeIfPossible)
+}
+
+function decodeIfPossible($0, $1) {
+  return decode($1) || $0
+}