Convert markdownlint library to an ECMAScript module, replace markdownlint-micromark with micromark, stop publishing (large) markdownlint-browser.js, see https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c for guidance.

lib/md004.mjs

@@ -0,0 +1,83 @@
+// @ts-check
+
+import { addErrorDetailIf } from "../helpers/helpers.cjs";
+import { getDescendantsByType, getParentOfType } from "../helpers/micromark-helpers.cjs";
+import { filterByTypesCached } from "./cache.mjs";
+
+const markerToStyle = {
+  "-": "dash",
+  "+": "plus",
+  "*": "asterisk"
+};
+const styleToMarker = {
+  "dash": "-",
+  "plus": "+",
+  "asterisk": "*"
+};
+const differentItemStyle = {
+  "dash": "plus",
+  "plus": "asterisk",
+  "asterisk": "dash"
+};
+const validStyles = new Set([
+  "asterisk",
+  "consistent",
+  "dash",
+  "plus",
+  "sublist"
+]);
+
+/** @type {import("./markdownlint.mjs").Rule} */
+export default {
+  "names": [ "MD004", "ul-style" ],
+  "description": "Unordered list style",
+  "tags": [ "bullet", "ul" ],
+  "parser": "micromark",
+  "function": function MD004(params, onError) {
+    const style = String(params.config.style || "consistent");
+    let expectedStyle = validStyles.has(style) ? style : "dash";
+    const nestingStyles = [];
+    for (const listUnordered of filterByTypesCached([ "listUnordered" ])) {
+      let nesting = 0;
+      if (style === "sublist") {
+        /** @type {import("../helpers/micromark-helpers.cjs").Token | null} */
+        let parent = listUnordered;
+        // @ts-ignore
+        while ((parent = getParentOfType(parent, [ "listOrdered", "listUnordered" ]))) {
+          nesting++;
+        }
+      }
+      const listItemMarkers = getDescendantsByType(listUnordered, [ "listItemPrefix", "listItemMarker" ]);
+      for (const listItemMarker of listItemMarkers) {
+        const itemStyle = markerToStyle[listItemMarker.text];
+        if (style === "sublist") {
+          if (!nestingStyles[nesting]) {
+            nestingStyles[nesting] =
+              (itemStyle === nestingStyles[nesting - 1]) ?
+                differentItemStyle[itemStyle] :
+                itemStyle;
+          }
+          expectedStyle = nestingStyles[nesting];
+        } else if (expectedStyle === "consistent") {
+          expectedStyle = itemStyle;
+        }
+        const column = listItemMarker.startColumn;
+        const length = listItemMarker.endColumn - listItemMarker.startColumn;
+        addErrorDetailIf(
+          onError,
+          listItemMarker.startLine,
+          expectedStyle,
+          itemStyle,
+          undefined,
+          undefined,
+          [ column, length ],
+          {
+            "editColumn": column,
+            "deleteCount": length,
+            "insertText": styleToMarker[expectedStyle]
+          }
+        );
+      }
+    }
+  }
+};