feat: expose exitcode in error instance (#9)

Author: ottomao

index.js

@@ -96,6 +96,7 @@ module.exports = function runScript(script, options, extraOptions) {
         const err = new Error(`Run "${sh} ${shFlag} ${script}" error, exit code ${code}`);
         err.name = 'RunScriptError';
         err.stdio = stdio;
+        err.exitcode = code;
         return reject(err);
       }
       return resolve(stdio);

test/runscript.test.js

@@ -23,6 +23,7 @@ describe('test/runscript.test.js', () => {
       .catch(err => {
         console.log(err);
         assert(err.name === 'RunScriptError');
+        assert(err.exitcode === 255);
       });
   });