Test for an addon failed in ember-source@7.0.0-beta.1 and ember-source@7.1.0-alpha.4

[ijlee2]

🐞 Describe the Bug

In embroider-css-modules, one of my rendering tests failed when I re-enabled ember-beta and ember-canary scenarios.

not ok 15 Chrome 147.0 - [38 ms] - Integration | Helper | local > When styles is undefined: throws an error when there are local class names (only in development environment)
    ---
        stack: >
            TypeError: Cannot read properties of null (reading 'firstNode')
                at Ly.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224080)
                at zy.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at Ly.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at zy.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at Ly.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at zy.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at Ly.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at zy.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at Ly.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
                at zy.firstNode (http://localhost:38705/assets/app-DAwB9tRf.js:1:224081)
        message: >
            Promise rejected after "throws an error when there are local class names (only in development environment)": Cannot read properties of null (reading 'firstNode')

Here is the {{local}} helper in question: packages/embroider-css-modules/src/helpers/local.ts. It uses assert from @ember/debug.

🔬 Minimal Reproduction

Pull request: ijlee2/embroider-css-modules#247
CI logs: ember-lts-6.12, ember-beta, ember-canary

😕 Actual Behavior

A clear and concise description of what is happening.

🤔 Expected Behavior

A clear and concise description of what you expected to happen.

🌍 Environment

• Ember: 6.12.0 (updated to 7.0.0-beta.1 and 7.1.0-alpha.4 using @embroider/try)
• Ember-CLI: 6.12.0
• Node.js/npm: 22
• OS: Mac
• Browser: -

➕ Additional Context

I was able to enable ember-beta and ember-canary in two other addons without issues, so I think we can eliminate setups for CI and @embroider/try.

• ember-container-query
• ember-intl

[void-mAlex]

short answer is

vite build --mode needs to be development

and you need NODE_ENV=development

[ijlee2]

--mode needs to be development

@void-mAlex Ah, good to know. Thanks!

[kategengler]

Sounds like it was a setup issue