add possibility to parse toml files like pyproject.toml

README.md

@@ -88,7 +88,7 @@ Because this option makes changes to the input files, it is good to make a backu
 
 `markdownlint-cli` reuses [the rules][rules] from `markdownlint` package.
 
-Configuration is stored in JSON, JSONC, YAML, or INI files in the same [config format][config].
+Configuration is stored in JSON, JSONC, YAML, INI, or TOML files in the same [config format][config].
 
 A sample configuration file:
 
@@ -102,6 +102,14 @@ A sample configuration file:
 }
 ```
 
+```toml
+default = true
+heading-style = { style = "atx_closed" }
+ul-indent = { indent = 4 }
+no-hard-tabs = false
+whitespace = false
+```
+
 For more examples, see [.markdownlint.jsonc][markdownlint-jsonc], [.markdownlint.yaml][markdownlint-yaml], or the [style folder][style-folder].
 
 The CLI argument `--config` is not required.

markdownlint.js

@@ -36,15 +36,19 @@ function yamlParse(text) {
   return require('js-yaml').load(text);
 }
 
+function tomlParse(text) {
+  return require('toml').parse(text);
+}
+
 const exitCodes = {
   lintFindings: 1,
   failedToWriteOutputFile: 2,
   failedToLoadCustomRules: 3,
   unexpectedError: 4
 };
 
-const projectConfigFiles = ['.markdownlint.jsonc', '.markdownlint.json', '.markdownlint.yaml', '.markdownlint.yml'];
-const configParsers = [jsoncParse, yamlParse];
+const projectConfigFiles = ['.markdownlint.jsonc', '.markdownlint.json', '.markdownlint.yaml', '.markdownlint.yml', '.markdownlint.toml'];
+const configParsers = [jsoncParse, yamlParse, tomlParse];
 const fsOptions = {encoding: 'utf8'};
 const processCwd = process.cwd();
 
@@ -53,6 +57,7 @@ function readConfiguration(userConfigFile) {
 
   // Load from well-known config files
   let config = rc('markdownlint', {});
+
   for (const projectConfigFile of projectConfigFiles) {
     try {
       fs.accessSync(projectConfigFile, fs.R_OK);

package.json

@@ -45,7 +45,8 @@
     "jsonc-parser": "~3.2.1",
     "markdownlint": "~0.33.0",
     "minimatch": "~9.0.3",
-    "run-con": "~1.3.2"
+    "run-con": "~1.3.2",
+    "toml": "^3.0.0"
   },
   "devDependencies": {
     "ava": "^6.1.1",

test/config-files/toml/.markdownlint.toml

@@ -0,0 +1,2 @@
+[no-trailing-punctuation]
+punctuation="$"

test/config-files/toml/heading-dollar.md

@@ -0,0 +1,3 @@
+# Heading$
+
+Text

test/md043-config.js

@@ -6,6 +6,6 @@
 module.exports = {
   MD012: false,
   MD043: {
-    headers: ['# First', '## Second', '### Third']
+    headings: ['# First', '## Second', '### Third']
   }
 };

test/md043-config.json

@@ -1,7 +1,7 @@
 {
   "MD012": false,
   "MD043": {
-    "headers": [
+    "headings": [
       "# First",
       "## Second",
       "### Third"

test/md043-config.toml

@@ -0,0 +1,2 @@
+MD012 = false
+MD043 = { headings = ["# First", "## Second", "### Third"] }

test/test.js

@@ -400,6 +400,13 @@ test('configuration file can be JavaScript', async t => {
   t.is(result.exitCode, 0);
 });
 
+test('configuration file can be TOML', async t => {
+  const result = await execa('../markdownlint.js', ['--config', 'md043-config.toml', 'md043-config.md'], {stripFinalNewline: false});
+  t.is(result.stdout, '');
+  t.is(result.stderr, '');
+  t.is(result.exitCode, 0);
+});
+
 test('error on configuration file not found', async t => {
   try {
     await execa('../markdownlint.js', ['--config', 'non-existent-file-path.yaml', 'correct.md'], {stripFinalNewline: false});
@@ -441,6 +448,8 @@ test('.markdownlint.jsonc in cwd is used automatically', getCwdConfigFileTest('j
 
 test('.markdownlint.json in cwd is used automatically', getCwdConfigFileTest('json'));
 
+test('.markdownlint.toml in cwd is used automatically', getCwdConfigFileTest('toml'));
+
 test('.markdownlint.yaml in cwd is used automatically', getCwdConfigFileTest('yaml'));
 
 test('.markdownlint.yml in cwd is used automatically', getCwdConfigFileTest('yml'));