Adding additional checks for error type

Author: Joshua Causey

src/IncrementalChecker.ts

@@ -240,7 +240,10 @@ class IncrementalChecker {
       } catch (e) {
         if (
           fs.existsSync(fileName) &&
-          !e.message.trim().startsWith("Invalid source file")
+          // check the error type due to file system lag
+          !(e instanceof Error) &&
+          !(e.constructor.name === 'FatalError') &&
+          !(e.message && e.message.trim().startsWith('Invalid source file')
         ) {
           // it's not because file doesn't exist - throw error
           throw e;