Account for default filePath value set by ESLint

lib/parse.js

@@ -3,10 +3,24 @@
 const babylonToEspree = require("./babylon-to-espree");
 const { parseSync: parse, tokTypes: tt, traverse } = require("@babel/core");
 
+/*
+ * A filePath may not exist when the --stdin option is used on the command line or
+ * CLIEngine#executeOnText() is used programmatically. When it doesn't exist, ESLint sets
+ * the filePath to "<text>".
+ *
+ * https://eslint.org/docs/user-guide/command-line-interface#using-stdin
+ * https://eslint.org/docs/developer-guide/nodejs-api#cliengineexecuteontext
+ * https://github.com/eslint/eslint/blob/master/lib/cli-engine.js#L177
+ */
+const ESLINT_DEFAULT_FILEPATH = "<text>";
+
 module.exports = function(code, options) {
   const opts = {
     sourceType: options.sourceType,
-    filename: options.filePath,
+    filename:
+      options.filePath && options.filePath !== ESLINT_DEFAULT_FILEPATH
+        ? options.filePath
+        : undefined,
     cwd: options.babelOptions.cwd,
     root: options.babelOptions.root,
     rootMode: options.babelOptions.rootMode,