feat: Allow customizing empty-period fill value

[pulpdrew]

Closes HDX-3220
Closes HDX-1718
Closes HDX-3205

Summary

This PR adds an option that allows users to customize the 0-fill behavior on time charts. The default behavior remains to fill all empty intervals with 0. The user can now disable the filling behavior. When fill is disabled, series will appear to be interpolated.

This PR also consolidates various display settings into a drawer, replacing the existing Number Format drawer. In the process, various form-related bugs were fixed in the drawer, and micro/nano second input factors were added.

New Chart Display Settings Drawer

Zero-fill behavior

Enabled (default):

Disabled:

[changeset-bot]

🦋 Changeset detected

Latest commit: 5621c37

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@hyperdx/app	Patch
@hyperdx/api	Patch

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Project	Deployment	Review	Updated (UTC)
hyperdx-v2-oss-app	Ready	Preview, Comment	Jan 21, 2026 10:13pm

[claude]

PR Review: Custom Empty-Period Fill Value

Critical Issues

❌ Missing validation for custom fill values → The UI hardcodes fillNulls to 0 or false, but the type allows number | false. Add UI support for custom numeric values or restrict the type.

⚠️ Inconsistent logic in shouldFillNullsWithZero → Function name suggests zero-fill but actually checks if filling is enabled (ChartUtils.tsx:1162-1167). Rename to shouldFillNulls or change implementation.

⚠️ Missing data re-fetch on settings change → Removed useEffect hooks that triggered searches when alignDateRangeToGranularity and compareToPreviousPeriod changed (DBEditTimeChartForm.tsx:512-538). Settings changes now require manual re-submit. Either restore the effects or document the behavior change.

Code Quality

⚠️ Incomplete test coverage for fillNulls → Tests only cover true/false for generateEmptyBuckets, but the actual type is number | false. Add test for custom numeric fill values if supported.

⚠️ Dead code in test → Factor multiplication test was changed but test name wasn't updated (utils.test.ts:174-182). Either remove the test or fix the assertion to match the intended behavior.

Minor

✅ Good: Consolidated settings into a single drawer improves UX
✅ Good: Added connectNulls to chart for better line continuity
✅ Good: Comprehensive test coverage for new generateEmptyBuckets behavior

[github-actions]

E2E Test Results

✅ All tests passed • 60 passed • 4 skipped • 752s

Status	Count
✅ Passed	60
❌ Failed	0
⚠️ Flaky	1
⏭️ Skipped	4

Tests ran across 4 shards in parallel.

View full report →

[wrn14897]

style: its better to create an enum for the output

[pulpdrew]

The existing NumberFormat type already ensures that the value of output is one of 5 values, based on a zod schema:

z.enum(['currency', 'percent', 'byte', 'time', 'number'])

[wrn14897]

saw that. I meant we can create a ts enum and use z.nativeEnum there so we don't need to hardcode a fixed string

[pulpdrew]

Ah I understand. Thanks - I will update that if I come across it again in the future.

[wrn14897]

Great feature!