fix(victory-core): range() drops start value when end is 0

[chatman-media]

Bug

Helpers.range decides whether an end argument was supplied using a truthy check (end ? ... : ...). A literal 0 end is falsy, so it is mistaken for "no end given" and the start value is silently dropped:

range(5, 0)     // → [0, 1, 2, 3, 4]   (expected [5, 4, 3, 2, 1])
range(10, 0)    // → [0, 1, ... 9]     (expected [10, 9, ... 1])
range(10, 0, 2) // → [0, 2, 4, 6, 8]   (expected [10, 8, 6, 4, 2])

This is inconsistent with every other descending case the function already supports — range(5, -5) and range(5, 1) both correctly descend; only the end === 0 case misbehaves, and 0 is the single value that trips the truthy check. The expected descending behavior matches the function's own existing tests (range(5, -5) → descending) and lodash's _.range(5, 0) → [5, 4, 3, 2, 1].

The JSDoc already describes the intent in terms of presence — "@param end [The end value] If this is defined, start is the start value" — so the truthy check is simply the wrong test.

Fix

Detect the end argument by presence (end === undefined) instead of truthiness. The follow-up if (!endIndex) endIndex = 0 guard is retained (and its comment clarified) so that range(NaN) / range() keep returning [] as before.

-  const startIndex = end ? start : 0;
+  const startIndex = end === undefined ? 0 : start;

-  let endIndex = end ? end : start;
+  let endIndex = end === undefined ? start : end;

Tests

• Added two regression tests covering range(5, 0) and range(10, 0, 2). Both fail on main (2 failed, 41 passed) and pass with the fix (43 passed).
• All pre-existing helpers.test.ts cases still pass — range(4), range(-4), range(1, 5), range(-5, 5), range(5, -5), increment cases, the floating-point length case, and the undefined/NaN start cases are unchanged.
• ESLint clean on the changed files. Changeset included (victory-core patch).

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🦋 Changeset detected

Latest commit: 6eada88

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

This PR includes changesets to release 30 packages

Name	Type
victory-core	Patch
victory-area	Patch
victory-axis	Patch
victory-bar	Patch
victory-box-plot	Patch
victory-brush-container	Patch
victory-brush-line	Patch
victory-candlestick	Patch
victory-canvas	Patch
victory-chart	Patch
victory-create-container	Patch
victory-cursor-container	Patch
victory-errorbar	Patch
victory-group	Patch
victory-histogram	Patch
victory-legend	Patch
victory-line	Patch
victory-pie	Patch
victory-polar-axis	Patch
victory-scatter	Patch
victory-selection-container	Patch
victory-shared-events	Patch
victory-stack	Patch
victory-tooltip	Patch
victory-voronoi-container	Patch
victory-voronoi	Patch
victory-zoom-container	Patch
victory	Patch
victory-native	Patch
victory-vendor	Patch

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