Changes in environment.js applied only on second save

[nfc036]

I have properties defined in config/environment.js, i.e. testProperty with value 1:

'use strict';
module.exports = function(environment) {
  let ENV = {
    testProperty: 1,  
    modulePrefix: 'testapp2',
    environment,
    rootURL: '/',
    locationType: 'auto',
...

To illustrate the problem I import ENV from config in application controller and show the current value of ENV.testProperty in the application template.
Changing the value of testProperty from 1=>2 triggers a live reload, but the value shown in the browser is still "1" instead of "2" as expected. When changing the value from 2=>3, live reload is triggered again but not "3" as expected but "2" is shown (the value from the update before the last change).
Additional information:

• when I add a console.log(ENV.testProperty') at the end of config/environment.js the console shows the (correct) current number twice before "Build successful".
• when I change any other file leading to a live reload, the current state of environment.js is still not reflected in the application. I have to trigger a second save on environment.js to get the correct content.
• restarting ember s always shows the current value correctly.

I noticed this with ember-cli@3.8.1 but checking with ember-cli@3.7.1 shows the same behaviour. It might be relevant that I'm working on windows.

---

Output from ember version --verbose && npm --version && yarn --version:

ember-cli: 3.8.1
http_parser: 2.7.0
node: 8.9.3
v8: 6.1.534.48
uv: 1.15.0
zlib: 1.2.11
ares: 1.10.1-DEV
modules: 57
nghttp2: 1.25.0
openssl: 1.0.2n
icu: 59.1
unicode: 9.0
cldr: 31.0.1
tz: 2017b
os: win32 x64
6.8.0
1.3.2

[rwjblue]

Hmm, I haven't seen/heard of this issue before now. I'll try to test tomorrow on OSX to see if the same thing is going on there and I just didn't notice...

[nfc036]

Thanks for looking into this, Robert. I didn't notice it before either. I checked one of my projects. When going back in time to Juli 2018 with ember-cli@3.3.0 everything worked as expected. In September 2018 I ugraded my app from ember-cli@3.3.0 to 3.4.2. The issue described above seems to start with this update.

[nfc036]

I noticed (using ember-cli@3.4.2) that broccoli is temporary creating files development.json and test.json in a config_loader-output_path-*/environments subdirectory. When changing config/environment.js and let ember-cli rebuild the application, test.json is correctly updated whereas development.json keeps the old content.

[nfc036]

While investigating this issue I noticed that when removing the if condition (to bypass the cache) here

ember-cli/lib/models/project.js

Lines 254 to 257 in c97dee8

	if (config === undefined) {
	config = this.configWithoutCache(env);
	this.configCache.set(key, config);
	}

changes in config/environment.js are applied on the first rebuild.

[gilgen]

@nfc036 I confirm this behaviour.

[colenso]

I'm experiencing the same behaviour.