New: option withNodeModules to unignore node_modules folders.

Author: reklatsmasters

README.md

@@ -121,6 +121,14 @@ For the list of every available exclusion rule set, please see the [readme of es
       }]
       ```
 
+    - `withNodeModules`: Prettier ignores files located in `node_modules` directories. To opt-out from this behavior set `true`, (default: `false`). May be useful if you are using multiple `node_modules` directories, example to avoid many `../..` sequences.
+    
+      ```json
+      "prettier/prettier": ["error", {}, {
+        "withNodeModules": true
+      }]
+      ```
+
 - The rule is autofixable -- if you run `eslint` with the `--fix` flag, your code will be formatted according to `prettier` style.
 
 ---

eslint-plugin-prettier.js

@@ -131,7 +131,8 @@ module.exports = {
           {
             type: 'object',
             properties: {
-              usePrettierrc: { type: 'boolean' }
+              usePrettierrc: { type: 'boolean' },
+              withNodeModules: { type: 'boolean' }
             },
             additionalProperties: true
           }
@@ -140,6 +141,8 @@ module.exports = {
       create(context) {
         const usePrettierrc =
           !context.options[1] || context.options[1].usePrettierrc !== false;
+        const withNodeModules =
+          context.options[1] && context.options[1].withNodeModules !== false;
         const sourceCode = context.getSourceCode();
         const filepath = context.getFilename();
         const source = sourceCode.text;
@@ -164,7 +167,8 @@ module.exports = {
               : null;
 
             const prettierFileInfo = prettier.getFileInfo.sync(filepath, {
-              ignorePath: '.prettierignore'
+              ignorePath: '.prettierignore',
+              withNodeModules
             });
 
             // Skip if file is ignored using a .prettierignore file