"TypeError: Cannot set property message of which has only a getter"

[chharvey]

pug-runtime/index.js

Line 251 in 8647d82

err.message = (filename || 'Pug') + ':' + lineno

It appears as if pug_rethrow is attempting to set the message property of something, where message is only a getter.

Setting err.message = .. throws a TypeError, which reads:

TypeError: Cannot set property message of  which has only a getter

I’m not sure why, because the message property of any Error object should be settable. It might be the case that err is not actually an Error object.

Specs:

• node.js v8.9.1
• npm@5.7.1
• gulp-pug@3.3.0
• pug@2.0.0-rc.4
• pug-runtime@2.0.3

Trace:

events.js:183
      throw er; // Unhandled 'error' event
      ^
TypeError: Cannot set property message of  which has only a getter
    at Object.pug_rethrow [as rethrow] (/Users/Chris/Repositories/_CLONED/neo/node_modules/pug-runtime/index.js:251:15)
    at template (eval at wrap (/Users/Chris/Repositories/_CLONED/neo/node_modules/pug-runtime/wrap.js:6:10), :837:665)
    at DestroyableTransform.compilePug [as _transform] (/Users/Chris/Repositories/_CLONED/neo/node_modules/gulp-pug/index.js:36:49)
    at DestroyableTransform.Transform._read (/Users/Chris/Repositories/_CLONED/neo/node_modules/readable-stream/lib/_stream_transform.js:184:10)
    at DestroyableTransform.Transform._write (/Users/Chris/Repositories/_CLONED/neo/node_modules/readable-stream/lib/_stream_transform.js:172:83)
    at doWrite (/Users/Chris/Repositories/_CLONED/neo/node_modules/readable-stream/lib/_stream_writable.js:418:64)
    at writeOrBuffer (/Users/Chris/Repositories/_CLONED/neo/node_modules/readable-stream/lib/_stream_writable.js:407:5)
    at DestroyableTransform.Writable.write (/Users/Chris/Repositories/_CLONED/neo/node_modules/readable-stream/lib/_stream_writable.js:334:11)
    at write (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:623:24)
    at flow (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:632:7)
    at DestroyableTransform.pipeOnReadable (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:664:5)
    at emitNone (events.js:106:13)
    at DestroyableTransform.emit (events.js:208:7)
    at emitReadable_ (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:448:10)
    at emitReadable (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:444:5)
    at readableAddChunk (/Users/Chris/Repositories/_CLONED/neo/node_modules/vinyl-fs/node_modules/readable-stream/lib/_stream_readable.js:187:9)

[ForbesLindesay]

This is very odd. We actually check that it's instanceof Error before we do any of this. I would be happy to accept a pull request to wrap https://github.com/pugjs/pug/blob/master/packages/pug-runtime/index.js#L249-L251 in a try/catch block, so that we throw the original error if we were unable to update the message.

Please also note that this package has moved to the monorepo, so you'll need to put your pull request there: https://github.com/pugjs/pug/tree/master/packages/pug-runtime