goog.provide() under whitespaceonly optimizations doesn't work under node.js

[Kevin Lynagh]

If I understand correctly,

goog.provide ensures that objects exist so you can write:

goog.provide('a.b.c')
a.b.c = 17

and objects a and b will exist and the assignment will work fine.

Running node.js on base.js with those two lines appended to the end
throws an error; "a not defined".
The same script works fine if you load it into a browser.


Is this the expected behavior, or a bug?
From what I could tell looking at how goog.provide works, it seems
like just JavaScript and not browser/DOM specific at all.

[Michael Bolin]

The last time I looked at this, the problem was that Node does not like how goog.require() creates the global object "a" in your example.

To this end, I modified base.js slightly in plovr such that goog.provide() works in Node:

http://code.google.com/p/plovr/source/detail?r=f02969e4dd41623544325aca6e20f32b32c53615&path=/closure/closure-library/closure/goog/base.js

though it requires that you specify a --define "goog.NODE_JS=true" (see the commit message that I linked to for more details).

I haven't tried to upstream my change to Closure Library because I'm not convinced that it's the best way to do Node+Closure yet (though it is the best one that I have found).

I posted a more detailed response on StackOverflow:

http://stackoverflow.com/questions/8287597/getting-closure-compiler-and-node-js-to-play-nice

Though I'm a bit annoyed that the "Don't use Closure Compiler" is ranked above my answer...

[Nick Santos]

To be fair, I think "don't use the output of Closure Compiler on
Node.js" is a totally reasonable answer.

A while back, we tossed around the idea of having pluggable boot
loaders for different environments (see the code under
bootstrap/webworkers.js for a possible solution), but i agree with
Bolin that there's not really a satisfying answer to this yet.