Add --configPointer argument to allow embedding the configuration obj…

…ect in files like package.json and pyproject.toml (fixes #113, fixes #458).

README.md

@@ -26,20 +26,21 @@ markdownlint --help
   MarkdownLint Command Line Interface
 
   Options:
-    -V, --version                               output the version number
-    -c, --config [configFile]                   configuration file (JSON, JSONC, JS, YAML, or TOML)
-    -d, --dot                                   include files/folders with a dot (for example `.github`)
-    -f, --fix                                   fix basic errors (does not work with STDIN)
-    -i, --ignore [file|directory|glob]          file(s) to ignore/exclude (default: [])
-    -j, --json                                  write issues in json format
-    -o, --output [outputFile]                   write issues to file (no console)
-    -p, --ignore-path [file]                    path to file with ignore pattern(s)
-    -q, --quiet                                 do not write issues to STDOUT
-    -r, --rules  [file|directory|glob|package]  include custom rule files (default: [])
-    -s, --stdin                                 read from STDIN (does not work with files)
-    --enable [rules...]                         Enable certain rules, e.g. --enable MD013 MD041 --
-    --disable [rules...]                        Disable certain rules, e.g. --disable MD013 MD041 --
-    -h, --help                                  display help for command
+    -V, --version                              output the version number
+    -c, --config <configFile>                  configuration file (JSON, JSONC, JS, YAML, or TOML)
+    --configPointer <pointer>                  JSON Pointer to object within configuration file (default: "")
+    -d, --dot                                  include files/folders with a dot (for example `.github`)
+    -f, --fix                                  fix basic errors (does not work with STDIN)
+    -i, --ignore <file|directory|glob>         file(s) to ignore/exclude (default: [])
+    -j, --json                                 write issues in json format
+    -o, --output <outputFile>                  write issues to file (no console)
+    -p, --ignore-path <file>                   path to file with ignore pattern(s)
+    -q, --quiet                                do not write issues to STDOUT
+    -r, --rules <file|directory|glob|package>  include custom rule files (default: [])
+    -s, --stdin                                read from STDIN (does not work with files)
+    --enable <rules...>                        Enable certain rules, e.g. --enable MD013 MD041 --
+    --disable <rules...>                       Disable certain rules, e.g. --disable MD013 MD041 --
+    -h, --help                                 display help for command
 ```
 
 Or run using [Docker](https://www.docker.com) and [GitHub Packages](https://github.com/features/packages):
@@ -113,6 +114,9 @@ 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 object (per above).
+This argument can be used with any configuration file type 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.
 
@@ -156,6 +160,7 @@ MIT © Igor Shubovych
 [actions-badge]: https://github.com/igorshubovych/markdownlint-cli/workflows/CI/badge.svg?branch=master
 [actions-url]: https://github.com/igorshubovych/markdownlint-cli/actions?query=workflow%3ACI
 [commander-variadic]: https://github.com/tj/commander.js#variadic-option
+[json-pointer]: https://datatracker.ietf.org/doc/html/rfc6901
 [markdownlint]: https://github.com/DavidAnson/markdownlint
 [markdownlint-cli2]: https://github.com/DavidAnson/markdownlint-cli2
 [markdownlint-jsonc]: https://github.com/DavidAnson/markdownlint/blob/main/schema/.markdownlint.jsonc

markdownlint.js

@@ -12,6 +12,7 @@ const glob = require('glob');
 const markdownlint = require('markdownlint');
 const rc = require('run-con');
 const minimatch = require('minimatch');
+const jsonpointer = require('jsonpointer');
 const pkg = require('./package.json');
 
 const options = program.opts();
@@ -55,8 +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) {
@@ -71,9 +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) {
@@ -199,15 +199,16 @@ program
   .version(pkg.version)
   .description(pkg.description)
   .usage('[options] <files|directories|globs>')
-  .option('-c, --config <configFile>', 'configuration file (JSON, JSONC, JS, or YAML)')
+  .option('-c, --config <configFile>', 'configuration file (JSON, JSONC, JS, YAML, or TOML)')
+  .option('--configPointer <pointer>', 'JSON Pointer to object within configuration file', '')
   .option('-d, --dot', 'include files/folders with a dot (for example `.github`)')
   .option('-f, --fix', 'fix basic errors (does not work with STDIN)')
   .option('-i, --ignore <file|directory|glob>', 'file(s) to ignore/exclude', concatArray, [])
   .option('-j, --json', 'write issues in json format')
   .option('-o, --output <outputFile>', 'write issues to file (no console)')
   .option('-p, --ignore-path <file>', 'path to file with ignore pattern(s)')
   .option('-q, --quiet', 'do not write issues to STDOUT')
-  .option('-r, --rules  <file|directory|glob|package>', 'include custom rule files', concatArray, [])
+  .option('-r, --rules <file|directory|glob|package>', 'include custom rule files', concatArray, [])
   .option('-s, --stdin', 'read from STDIN (does not work with files)')
   .option('--enable <rules...>', 'Enable certain rules, e.g. --enable MD013 MD041 --')
   .option('--disable <rules...>', 'Disable certain rules, e.g. --disable MD013 MD041 --');
@@ -276,7 +277,8 @@ const diff = files.filter(file => !ignores.some(ignore => ignore.absolute === fi
 
 function lintAndPrint(stdin, files) {
   files ||= [];
-  const config = readConfiguration(options.config);
+  const configuration = readConfiguration(options.config);
+  const config = jsonpointer.get(configuration, options.configPointer) || {};
 
   for (const rule of options.enable || []) {
     // Leave default values in place if rule is an object

package.json

@@ -43,6 +43,7 @@
     "ignore": "~5.3.1",
     "js-yaml": "^4.1.0",
     "jsonc-parser": "~3.2.1",
+    "jsonpointer": "5.0.1",
     "markdownlint": "~0.34.0",
     "minimatch": "~9.0.4",
     "run-con": "~1.3.2",

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';