Fix: callback not invoked on Dropbox filesDownload error in Store.js

[Copilot]

• Analyze the issue: callback not invoked on filesDownload error in Store.js
• Fix Store.js to call callback in the .catch handler
• Add tests for Dropbox error/success callback invocation
• Run tests to validate the fix (49/49 passing)
• Fix CI build: regenerate package-lock.json with complete dependency tree
• Guard callback.call(self) with typeof callback === 'function' in both .then and .catch handlers to prevent TypeError when no callback is provided
• Replace new Blob(...) with plain {} object in test to avoid ReferenceError in older Node environments
• Code review and security check (no issues found)

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[Samuel3]

@copilot please fix build

[Copilot]

@copilot please fix build

Fixed in commit 6558261. The build was failing because running npm install --save-dev mocha@5 in the previous session upgraded package-lock.json from lockfileVersion 1 to 3, but the resulting file was missing packages like lodash.isplainobject that npm ci requires. Regenerated the lock file with npm install --package-lock-only --ignore-scripts to produce a complete dependency tree.

[Copilot]

Pull request overview

Fixes a Store initialization edge case where the provided callback was not invoked when Dropbox filesDownload fails, and adds regression tests around Dropbox initialization behavior.

Changes:

• Invoke the Store initialization callback from the Dropbox filesDownload .catch(...) handler.
• Add unit tests verifying callback invocation on Dropbox download success and failure.
• Update Mocha devDependency version.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.

File	Description
app/js/Store.js	Ensures the initialization callback is triggered when Dropbox download rejects.
test/store.test.js	Adds Dropbox init tests to assert callback invocation for success/error paths.
package.json	Bumps Mocha version used for running tests.

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[Copilot]

callback is invoked unconditionally here. If Store is constructed without a callback (the constructor already treats it as optional in the non-Dropbox path), this will throw a TypeError. Guard the invocation (e.g., only call when callback is a function) or provide a no-op default so the Dropbox error path can’t crash the app.

[Samuel3]

@copilot please fix

[Copilot]

Fixed in commit e713b5d. Both the .then (loadend) and .catch handlers now guard with typeof callback === 'function' before invoking callback.call(self).

[Copilot]

This test uses new Blob(...), but the unit tests run under plain Node (and this repo’s CI/build config includes Node 10 on Windows), where Blob is not available. Since the FileReader mock ignores the argument anyway, return a simple placeholder (or add a global.Blob polyfill in the test setup) to avoid ReferenceError: Blob is not defined in older Node environments.

Suggested change

	return Promise.resolve({
	fileBlob: new Blob([JSON.stringify({})], { type: 'application/json' })
	// Use a simple placeholder instead of Blob to avoid ReferenceError in Node
	return Promise.resolve({
	fileBlob: {}

[Samuel3]

@copilot please fix

[Copilot]

Fixed in commit e713b5d. Replaced new Blob([JSON.stringify({})], { type: 'application/json' }) with a plain {} object, which avoids the ReferenceError in Node environments where Blob is not globally available.