markdownlint/example/typescript/type-check.ts

// Attempt to validate important type declarations

import { Configuration, ConfigurationStrict, LintResults, Options, Rule, RuleParams, RuleOnError, RuleOnErrorInfo } from "../../lib/exports.mjs";
import { applyFix, applyFixes, getVersion } from "../../lib/exports.mjs";
import { lint as lintAsync, readConfig as readConfigAsync } from "../../lib/exports-async.mjs";
import { lint as lintPromise, readConfig as readConfigPromise } from "../../lib/exports-promise.mjs";
import { lint as lintSync, readConfig as readConfigSync } from "../../lib/exports-sync.mjs";

import assert from "assert";
import markdownIt from "markdown-it";
const markdownlintJsonPath = "../../.markdownlint.json";

const version: string = getVersion();
assert(/^\d+\.\d+\.\d+$/.test(version));

function assertConfiguration(config: Configuration) {
  assert(!!config);
  assert.deepEqual(config["line-length"], { "strict": true, "code_blocks": false });
  // config assignment is covered by markdownlint.Options
}

function assertConfigurationCallback(err: Error | null, config?: Configuration) {
  assert(!err);
  config && assertConfiguration(config);
}

function assertLintResults(results: LintResults) {
  assert(!!results);
  assert.equal(results["string"].length, 1);
  assert.equal(results["string"][0].lineNumber, 1);
  assert.deepEqual(results["string"][0].ruleNames, [ "MD047", "single-trailing-newline" ]);
  assert.equal(results["string"][0].ruleDescription, "Files should end with a single newline character");
  assert.equal(results["string"][0].ruleInformation.replace(/v\d+\.\d+\.\d+/, "v0.0.0"), "https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md047.md");
  assert.equal(results["string"][0].errorDetail, null);
  assert.equal(results["string"][0].errorContext, null);
  assert.deepEqual(results["string"][0].errorRange, [ 9, 1 ]);
  const fixInfo = results["string"][0].fixInfo;
  assert(!!fixInfo);
  if (fixInfo) {
    assert.equal(fixInfo.lineNumber, null);
    assert.equal(fixInfo.editColumn, 10);
    assert(!fixInfo.deleteCount);
    assert.equal(fixInfo.insertText, "\n");
  }
  assert.equal(results["../bad.md"].length, 2);
  // Deliberate assignment to unused variable validates types
  // False-positive for js/useless-assignment-to-local
  results = {
    "key": [
      {
        "lineNumber": 1,
        "ruleNames": [ "rule", "names" ],
        "ruleDescription": "description",
        "ruleInformation": "https://example.com/ruleInformation",
        "errorDetail": "detail",
        "errorContext": "context",
        "errorRange": [ 1, 2 ],
        "fixInfo": {
          "editColumn": 1,
          "deleteCount": 1,
          "insertText": "text"
        },
        "severity": "error"
      }
    ]
  };
}

function assertLintResultsCallback(err: Error | null, results?: LintResults) {
  assert(!err);
  results && assertLintResults(results);
}

assertConfiguration(readConfigSync(markdownlintJsonPath));
assertConfiguration(readConfigSync(markdownlintJsonPath, [ JSON.parse ]));

readConfigAsync(markdownlintJsonPath, assertConfigurationCallback);
readConfigAsync(markdownlintJsonPath, [ JSON.parse ], assertConfigurationCallback);

(async () => {
  assertConfigurationCallback(null, await readConfigPromise(markdownlintJsonPath));
  assertConfigurationCallback(null, await readConfigPromise(markdownlintJsonPath, [ JSON.parse ]))
})();

let options: Options;
options = {
  "files": [ "../bad.md" ],
  "strings": {
    "string": "# Heading"
  },
  "config": {
    "no-missing-space-atx": false,
    "no-hard-tabs": {
      "code_blocks": true
    }
  },
  "configParsers": [ JSON.parse ],
  "customRules": undefined,
  "frontMatter": /---/,
  "handleRuleFailures": false,
  "noInlineConfig": false,
  "markdownItFactory": () => markdownIt()
};

assertLintResults(lintSync(options));
lintAsync(options, assertLintResultsCallback);
(async () => {
  assertLintResultsCallback(null, await lintPromise(options));
})();

options.files = "../bad.md";
assertLintResults(lintSync(options));
lintAsync(options, assertLintResultsCallback);
(async () => {
  assertLintResultsCallback(null, await lintPromise(options));
})();

const testRule: Rule = {
  "names": [ "test-rule" ],
  "description": "Test rule",
  "information": new URL("https://example.com/rule-information"),
  "tags": [ "test-tag" ],
  "parser": "none",
  "function": function rule(params: RuleParams, onError: RuleOnError) {
    assert(!!params);
    assert(!!onError);
    let ruleParams: RuleParams;
    ruleParams = {
      "name": "name",
      "parsers": {
        "markdownit": {
          "tokens": []
        },
        "micromark": {
          "tokens": []
        }
      },
      "lines": [
        "one",
        "two"
      ],
      "frontMatterLines": [
        "three"
      ],
      "config": options.config,
      "version": "1.2.3"
    };
    assert(ruleParams);
    let ruleOnErrorInfo: RuleOnErrorInfo;
    ruleOnErrorInfo = {
      "lineNumber": 1,
      "detail": "detail",
      "context": "context",
      "information": new URL("https://example.com/error-information"),
      "range": [ 1, 2 ],
      "fixInfo": {
        "lineNumber": 1,
        "editColumn": 1,
        "deleteCount": 1,
        "insertText": "text"
      }
    };
    assert(ruleOnErrorInfo);
    false && onError(ruleOnErrorInfo);
  }
};

options.customRules = [ testRule ];
assertLintResults(lintSync(options));
lintAsync(options, assertLintResultsCallback);
(async () => {
  assertLintResultsCallback(null, await lintPromise(options));
})();

const needsFixing = "#  Heading\n";

assert.equal(
  applyFix(
    needsFixing,
    {
      "insertText": " ",
      "editColumn": 2,
      "deleteCount": 2
    },
    "\n"
  ),
  "# Heading\n"
);

assert.equal(
  applyFixes(
    needsFixing,
    lintSync({
      "strings": {
        needsFixing
      }
    })["needsFixing"]
  ),
  "# Heading\n"
);

const configuration: Configuration = {
  "custom-rule": true,
  "no-hard-tabs": false,
  "heading-style": {
    "style": "consistent"
  }
};
assert(configuration);
const configurationStrict: ConfigurationStrict = {
  // "custom-rule": true,
  "no-hard-tabs": false,
  "heading-style": {
    "style": "consistent"
  }
};
assert(configurationStrict);