fix: don't diff install size with first version

[43081j]

Most initial versions are empty or unfinished, so generally show up as a
large bump in file size to the 2nd version.

This is misleading so we should just skip those.

🔗 Linked issue

🧭 Context

📚 Description

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Project	Deployment	Actions	Updated (UTC)
npmx.dev	Ready	Preview, Comment	Mar 21, 2026 4:21am

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
docs.npmx.dev	Ignored	Preview	Mar 21, 2026 4:21am
npmx-lunaria	Ignored		Mar 21, 2026 4:21am

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 6a4f74cf-f91c-4138-9827-533eed633579

📥 Commits

Reviewing files that changed from the base of the PR and between df7d8c2 and 6f34fd2.

📒 Files selected for processing (1)

• test/nuxt/composables/use-install-size-diff.spec.ts

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📝 Walkthrough

Walkthrough

The change modifies the getComparisonVersion function in app/composables/useInstallSizeDiff.ts to enforce a stricter baseline requirement for installation size comparisons. The guard condition was updated from currentIdx <= 0 to currentIdx <= 1, which ensures the function returns null when the resolved version is either the first or second stable entry in the list. This prevents comparisons when there is insufficient historical data. An explanatory inline comment was added to document this behaviour. The change affects only internal logic with no impact on exported or public entity declarations.

Possibly related PRs

• feat: show a warning when significant size increase #1673: Modifies the same getComparisonVersion function in app/composables/useInstallSizeDiff.ts, tightening the guard for returning a comparison baseline.

Suggested reviewers

• danielroe
• trueberryless

🚥 Pre-merge checks | ✅ 1

✅ Passed checks (1 passed)

Check name	Status	Explanation
Description check	✅ Passed	The PR description directly addresses the changeset, explaining why the first version should be skipped for install-size comparisons.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch jg/big-diffs-in-early-days

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[coderabbitai]

🧹 Nitpick comments (1)

app/composables/useInstallSizeDiff.ts (1)

38-38: Consider removing the non-null assertion for strict type safety.

The non-null assertion operator bypasses TypeScript's type checking. Whilst the guard ensures the array access is logically safe, a defensive check would better align with the strict type-safety guideline.

🛡️ Proposed fix to add explicit bounds checking

- return stableVersions[currentIdx - 1]!
+ const prevVersion = stableVersions[currentIdx - 1]
+ if (!prevVersion) return null
+ return prevVersion

As per coding guidelines: "Ensure you write strictly type-safe code, for example by ensuring you always check when accessing an array value by index"

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: b223cee3-93cd-450d-9784-a20ca2248579

📥 Commits

Reviewing files that changed from the base of the PR and between 1cd901f and df7d8c2.

📒 Files selected for processing (1)

• app/composables/useInstallSizeDiff.ts

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

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