wip

README.md

@@ -99,8 +99,8 @@ JS configuration files contain JavaScript code, must have the `.js` or `.cjs` fi
 If your workspace _(project)_ is [ESM-only] _(`"type": "module"` set in the root `package.json` file)_, then the configuration file **should end with `.cjs` file extension**.
 A JS configuration file may internally `require` one or more npm packages as a way of reusing configuration across projects.
 
-The `--configPointer` argument allows the use of [JSON Pointer][json-pointer] syntax to identify a sub-object within the configuration file specified via `--config`.
-This works for any configuration file format and makes it possible to nest a configuration object within a more expansive file that (ex: `package.json` or `pyproject.toml`).
+The `--configPointer` argument allows the use of [JSON Pointer][json-pointer] syntax to identify a sub-object within the configuration object (per above).
+This argument can be used with any configuration file format and makes it possible to nest a configuration object within another file like `package.json` or `pyproject.toml` (e.g., via `/key` or `/key/subkey`).
 
 `--enable` and `--disable` override configuration files; if a configuration file disables `MD123` and you pass `--enable MD123`, it will be enabled.
 If a rule is passed to both `--enable` and `--disable`, it will be disabled.

markdownlint.js

@@ -56,8 +56,6 @@ const fsOptions = {encoding: 'utf8'};
 const processCwd = process.cwd();
 
 function readConfiguration(userConfigFile) {
-  const jsConfigFile = /\.c?js$/i.test(userConfigFile);
-
   // Load from well-known config files
   let config = rc('markdownlint', {});
   for (const projectConfigFile of projectConfigFiles) {
@@ -72,9 +70,10 @@ function readConfiguration(userConfigFile) {
   }
 
   // Normally parsing this file is not needed, because it is already parsed by rc package.
-  // However I have to do it to overwrite configuration from .markdownlint.{json,yaml,yml}.
+  // However I have to do it to overwrite configuration from .markdownlint.{jsonc,json,yaml,yml}.
   if (userConfigFile) {
     try {
+      const jsConfigFile = /\.c?js$/i.test(userConfigFile);
       const userConfig = jsConfigFile ? require(path.resolve(processCwd, userConfigFile)) : markdownlint.readConfigSync(userConfigFile, configParsers);
       config = require('deep-extend')(config, userConfig);
     } catch (error) {
@@ -279,7 +278,7 @@ const diff = files.filter(file => !ignores.some(ignore => ignore.absolute === fi
 function lintAndPrint(stdin, files) {
   files ||= [];
   const configuration = readConfiguration(options.config);
-  const config = jsonpointer.get(configuration, options.configPointer);
+  const config = jsonpointer.get(configuration, options.configPointer) || {};
 
   for (const rule of options.enable || []) {
     // Leave default values in place if rule is an object

test/nested-config.json

@@ -0,0 +1,8 @@
+{
+  "name": "unused",
+
+  "key": {
+    "blanks-around-headings": false,
+    "commands-show-output": false
+  }
+}

test/nested-config.toml

@@ -0,0 +1,7 @@
+name = "unused"
+
+[key]
+other-name = "unused"
+
+[key.subkey]
+commands-show-output = false

test/test.js

@@ -489,6 +489,50 @@ test('.markdownlint.yaml in cwd is used instead of .markdownlint.yml', getCwdCon
 
 test('.markdownlint.json with JavaScript-style comments is handled', getCwdConfigFileTest('json-c'));
 
+test('invalid JSON Pointer', async t => {
+  try {
+    await execa('../markdownlint.js', ['--config', 'nested-config.json', '--configPointer', 'INVALID', '**/*.md'], {stripFinalNewline: false});
+    t.fail();
+  } catch (error) {
+    t.is(error.stdout, '');
+    t.regex(error.stderr, /Invalid JSON pointer\./);
+    t.is(error.exitCode, 4);
+  }
+});
+
+test('empty JSON Pointer', async t => {
+  try {
+    await execa('../markdownlint.js', ['--config', 'nested-config.json', '--configPointer', '/EMPTY', 'incorrect.md'], {stripFinalNewline: false});
+    t.fail();
+  } catch (error) {
+    t.is(error.stdout, '');
+    t.is(error.stderr.match(errorPattern).length, 7);
+    t.is(error.exitCode, 1);
+  }
+});
+
+test('valid JSON Pointer with JSON configuration', async t => {
+  try {
+    await execa('../markdownlint.js', ['--config', 'nested-config.json', '--configPointer', '/key', 'incorrect.md'], {stripFinalNewline: false});
+    t.fail();
+  } catch (error) {
+    t.is(error.stdout, '');
+    t.is(error.stderr.match(errorPattern).length, 1);
+    t.is(error.exitCode, 1);
+  }
+});
+
+test('valid JSON Pointer with TOML configuration', async t => {
+  try {
+    await execa('../markdownlint.js', ['--config', 'nested-config.toml', '--configPointer', '/key/subkey', 'incorrect.md'], {stripFinalNewline: false});
+    t.fail();
+  } catch (error) {
+    t.is(error.stdout, '');
+    t.is(error.stderr.match(errorPattern).length, 3);
+    t.is(error.exitCode, 1);
+  }
+});
+
 test('Custom rule from single file loaded', async t => {
   try {
     const input = '# Input\n';