feat: add setting to select current working directory indicator file

package.json

@@ -154,6 +154,13 @@
           "type": "string",
           "default": "",
           "order": 5
+        },
+        "cwdIndicatorFile": {
+          "title": "Current working directory indicator file",
+          "description": "Attempt to find this file and use it's location as eslint's current working directory (requires restart).",
+          "type": "string",
+          "default": "",
+          "order": 6
         }
       }
     }

src/worker-helpers.js

@@ -139,6 +139,17 @@ export function getConfigPath(fileDir) {
 }
 
 export function getRelativePath(fileDir, filePath, config, projectPath) {
+  // If a current working directory indicator file is specified, try to find it to determine cwd
+  if (config.advanced.cwdIndicatorFile) {
+    const indicatorFile = findCached(fileDir, config.advanced.cwdIndicatorFile)
+
+    if (indicatorFile) {
+      const indicatorDir = Path.dirname(indicatorFile)
+      process.chdir(indicatorDir)
+      return Path.relative(indicatorDir, filePath)
+    }
+  }
+
   const ignoreFile = config.advanced.disableEslintIgnore ? null : findCached(fileDir, '.eslintignore')
 
   // If we can find an .eslintignore file, we can set cwd there