Bug 240715 – Web Inspector: Assertion Failed: Expect an array of string values CSSCompletions.js:39

• Component: Web Inspector
• Status: RESOLVED FIXED

[Razvan Caliman]

```
[Error] Assertion Failed: Expect an array of string values – [] (0)
    CSSCompletions (CSSCompletions.js:39)
    (anonymous function) (CSSKeywordCompletions.js:233)
    (anonymous function) (CSSKeywordCompletions.js:129)
    _valueCompletionDataProvider
    _updateCompletions (SpreadsheetTextField.js:435)
    _handleInput (SpreadsheetTextField.js:422)
    _handleInput
```

**Steps to reproduce**

- Open Web Inspector, go to Styles sidebar panel
- Type `var(` on any CSS value

**Result**

No issue in UI or UX, but the assertion above is hit.


**Explanation**

It happens because the `WI.CSSCompletions` instance created in `WI.CSSKeywordCompletions.forFunction()` is initially given an empty array for "var" functions. The actual values are added immediately after instantiation via `WI.CSSCompletions.addValues()`. They come from the custom completion provider referenced by the `additionalFunctionValueCompletionsProvider` option.

There's no reason to have this two step approach. We can provide the result of `additionalFunctionValueCompletionsProvider("var")` at `WI.CSSCompletions` instantiation.

[Radar WebKit Bug Importer]

<rdar://problem/93653315>

[Razvan Caliman]

Pull request: https://github.com/WebKit/WebKit/pull/831

[EWS]

Committed r294763 (250929@main): <https://commits.webkit.org/250929@main>

Reviewed commits have been landed. Closing PR #831 and removing active labels.