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.

test/markdownlint-test-scenarios.mjs

@@ -0,0 +1,113 @@
+// @ts-check
+
+import fs from "node:fs/promises";
+import path from "node:path";
+import test from "ava";
+import libMarkdownlint from "../lib/markdownlint.mjs";
+const { applyFixes, promises } = libMarkdownlint;
+const { markdownlint } = promises;
+import helpers from "../helpers/helpers.cjs";
+import { fixableRuleNames } from "../lib/constants.mjs";
+
+const numericalSortCompareFn = (a, b) => a - b;
+
+/**
+ * Create a test function for the specified test file.
+ *
+ * @param {string} file Test file relative path.
+ * @returns {import("ava").Implementation<unknown[]>} Test function.
+ */
+function createTestForFile(file) {
+  return (t) => (
+    // Read and lint Markdown test file
+    Promise.all([
+      fs.readFile(file, "utf8"),
+      markdownlint({
+        "files": [ file ]
+      })
+    ])
+      // Compare expected results and snapshot
+      .then((params) => {
+        const [ content, results ] = params;
+        // Canonicalize version number
+        const errors = results[file]
+          .filter((error) => !!error.ruleInformation);
+        for (const error of errors) {
+          error.ruleInformation =
+              error.ruleInformation.replace(/v\d+\.\d+\.\d+/, "v0.0.0");
+        }
+        // Match identified issues by MD### markers
+        const marker = /\{(MD\d+)(?::([-+]?)(\d+))?\}/g;
+        const lines = content.split(helpers.newLineRe);
+        const expected = {};
+        // @ts-ignore
+        for (const [ index, line ] of lines.entries()) {
+          let match = null;
+          while ((match = marker.exec(line))) {
+            const [ , rule, delta, value ] = match;
+            let lineNumber = index + 1;
+            if (value) {
+              const valueInt = Number.parseInt(value, 10);
+              if (delta) {
+                lineNumber += ((delta === "+") ? 1 : -1) * valueInt;
+              } else {
+                lineNumber = valueInt;
+              }
+            }
+            // eslint-disable-next-line no-multi-assign
+            const indices = expected[rule] = expected[rule] || [];
+            if (!indices.includes(lineNumber)) {
+              indices.push(lineNumber);
+            }
+          }
+        }
+        for (const list of Object.values(expected)) {
+          list.sort(numericalSortCompareFn);
+        }
+        const actual = {};
+        for (const error of errors) {
+          const rule = error.ruleNames[0];
+          // eslint-disable-next-line no-multi-assign
+          const indices = actual[rule] = actual[rule] || [];
+          if (indices[indices.length - 1] !== error.lineNumber) {
+            indices.push(error.lineNumber);
+          }
+          t.true(
+            !error.fixInfo || fixableRuleNames.includes(rule),
+            `Fixable rule ${rule} is not tagged as such.`
+          );
+        }
+        for (const list of Object.values(actual)) {
+          list.sort(numericalSortCompareFn);
+        }
+        t.deepEqual(actual, expected, "Too few or too many issues found.");
+        // Create snapshot
+        const fixed = applyFixes(content, errors)
+          .replace(/\r\n/g, "\n");
+        t.snapshot({
+          errors,
+          fixed
+        });
+        // Identify missing fixes
+        return markdownlint({
+          "strings": {
+            "input": fixed
+          }
+        }).then((fixedResults) => {
+          const unfixed = fixedResults.input.filter((error) => !!error.fixInfo);
+          t.deepEqual(unfixed, [], "Fixable error(s) not fixed.");
+        });
+      })
+      .catch()
+  );
+}
+
+const dir = await fs.readdir("./test");
+const files = dir.filter((file) => /\.md$/.test(file));
+for (const file of files) {
+  // @ts-ignore
+  test(
+    file,
+    createTestForFile(path.join("./test", file))
+  );
+}