Reviewing files that changed from the base of the PR and between d52345f and eafee34.

• scripts/snapshots/es6Files.txt
• scripts/snapshots/libFiles.txt
• scripts/snapshots/typesFiles.txt
• src/cartesian/Scatter.tsx
• src/chart/Treemap.tsx
• src/shape/Rectangle.tsx
• src/state/cartesianAxisSlice.ts
• src/state/externalEventsMiddleware.ts
• src/state/keyboardEventsMiddleware.ts
• src/state/mouseEventsMiddleware.ts
• src/state/polarOptionsSlice.ts
• src/state/selectors/areaSelectors.ts
• src/state/selectors/axisSelectors.ts
• src/state/selectors/barSelectors.ts
• src/state/selectors/combiners/combineAllBarPositions.ts
• src/state/selectors/combiners/combineBarPosition.ts
• src/state/selectors/combiners/combineBarSizeList.ts
• src/state/selectors/combiners/combineStackedData.ts
• src/state/selectors/containerSelectors.ts
• src/state/selectors/pieSelectors.ts
• src/state/selectors/polarScaleSelectors.ts
• src/state/selectors/polarSelectors.ts
• src/state/selectors/radialBarSelectors.ts
• src/state/selectors/rootPropsSelectors.ts
• src/state/selectors/scatterSelectors.ts
• src/util/ChartUtils.ts
• test/cartesian/XAxis/XAxis.state.spec.tsx
• test/cartesian/XAxis/XAxis.vertical.spec.tsx
• test/cartesian/YAxis/YAxis.spec.tsx
• test/cartesian/YAxis/YAxis.ticks.spec.tsx
• test/chart/RadialBarChart.5966.spec.tsx
• test/polar/RadialBar.spec.tsx

• GitHub Check: Build, Test, Pack
• GitHub Check: Analyze (javascript-typescript)

src/state/keyboardEventsMiddleware.ts (1)

16-16: LGTM: Type safety improvement.

Adding the <RechartsRootState> generic parameter enhances type inference within listener effects and aligns the middleware declaration with its usage.

src/state/externalEventsMiddleware.ts (1)

21-21: LGTM: Consistent type safety improvement.

The middleware now correctly declares its state type, matching the pattern applied across all middleware files in this PR.

src/state/mouseEventsMiddleware.ts (1)

12-12: LGTM: Type safety improvements for both middleware instances.

Both mouseClickMiddleware and mouseMoveMiddleware now correctly specify their state type, improving type inference and consistency across the codebase.

Also applies to: 34-34

src/state/selectors/combiners/combineStackedData.ts (1)

17-17: LGTM! Improved type safety.

The explicit | undefined type annotation correctly reflects that accessing stackGroups[stackId] may not return a value when the key doesn't exist. This improves type correctness and aligns with the PR's goal of adding more undefined checks.

src/state/polarOptionsSlice.ts (4)

12-14: LGTM: Type safety improvements.

The explicit PolarChartState type alias and typed initialState constant improve type safety for strict mode. The union with null correctly represents the uninitialized state.

---

16-20: LGTM: Reducer correctly typed with explicit return type.

The reducer is properly typed with explicit parameter and return types. The return type PolarChartOptions is narrower than the state type PolarChartState (which includes null), which correctly represents that this reducer transitions state from potentially null to a defined value. The unused _state parameter is appropriately prefixed with an underscore.

---

22-26: LGTM: Explicit generic types improve type safety.

The explicit generic type parameters createSlice<PolarChartState, typeof reducers> provide better type inference and compile-time type checking. This follows Redux Toolkit best practices and aligns with the PR's goal of improving type safety.

---

30-30: LGTM: Appropriate reducer export.

The polarOptionsReducer export follows Redux naming conventions and provides a clean public API for the slice.

src/state/selectors/pieSelectors.ts (2)

77-77: LGTM: Type annotation improves clarity.

Making the cells parameter type explicit aligns with the coding guideline to type parameters explicitly rather than relying on inference. The type correctly matches what pickCells returns, and the existing optional chaining on line 85 already handles undefined cells safely.

---

111-111: LGTM: Explicit typing enhances type safety.

The explicit PieSettings | undefined annotation correctly reflects the return type of selectSynchronisedPieSettings and maintains consistency with the pattern established on line 42. The undefined guard at line 115 ensures safe usage.

src/shape/Rectangle.tsx (2)

31-31: LGTM: Best practice improvement.

Using Array.isArray() instead of instanceof Array is more reliable across different execution contexts and is the recommended approach for array type checking.

---

34-35: LGTM: Defensive undefined handling.

The nullish coalescing operator (?? 0) appropriately handles cases where the radius array might have fewer than 4 elements at runtime, despite the tuple type definition. The explicit type annotation on r follows coding guidelines, and the intermediate variable improves readability while avoiding duplicate array access.

src/state/cartesianAxisSlice.ts (2)

205-205: Defensive type safety improvement.

The nullish coalescing operator correctly handles TypeScript's strict undefined checks. Although the history.length === 3 guard on line 201 ensures history[0] exists at runtime, TypeScript doesn't narrow array element types based on length checks. This defensive change aligns with the PR's goal of improving undefined handling.

---

210-214: Correct axis update pattern.

The object spread correctly preserves all properties from the current axis while updating width and widthHistory. This ensures no other axis properties are lost during the update.

src/cartesian/Scatter.tsx (3)

680-684: LGTM! Type signatures properly support optional axis data.

The parameter types correctly reflect that zAxis and tick arrays may be undefined. The function body handles these cases with appropriate guards at lines 688-689, 719, and 748.

---

719-730: LGTM! Proper guard for optional z-axis data.

The null check ensures z-axis data is only added to the tooltip payload when zAxis is defined, preventing undefined access.

---

748-748: LGTM! Safe size calculation with proper fallback.

The null check ensures zAxis.scale is only accessed when zAxis is defined, with a sensible fallback to defaultZ.

src/state/selectors/scatterSelectors.ts (2)

9-9: LGTM! Import additions support the type signature changes.

The TickItem import is required for the updated parameter types in the combiner function.

Also applies to: 18-18

---

60-65: LGTM! Return type correctly reflects optional z-axis.

The undefined return type properly handles cases where z-axis data is unavailable.

src/state/selectors/areaSelectors.ts (1)

124-125: LGTM! Type annotation now accurately reflects undefined possibility.

The type annotation change correctly acknowledges that stackedData can be undefined, and the code safely handles this with optional chaining on line 125.

src/chart/Treemap.tsx (4)

211-213: LGTM! Defensive null check prevents potential runtime errors.

The added null check in horizontalPosition safely skips processing when a child is null, preventing potential crashes.

---

248-250: LGTM! Defensive null check prevents potential runtime errors.

The added null check in verticalPosition safely skips processing when a child is null, preventing potential crashes.

---

301-306: LGTM! Proper null handling in squarify logic.

The code correctly checks if the first element is null before using it, then pushes the non-null child to the row. This prevents potential runtime errors when processing children.

---

899-901: LGTM! Proper null check for touch event.

The early return when the first touch event is null prevents potential crashes in touch handling.

scripts/snapshots/libFiles.txt (1)

142-142: LGTM! Snapshot updated for new combiner module.

The addition of lib/state/selectors/combiners/combineBarPosition.js correctly reflects the new combiner module introduced in this PR.

scripts/snapshots/es6Files.txt (1)

142-142: LGTM! ES6 snapshot updated for new combiner module.

The addition correctly reflects the new combiner module in the ES6 build output.

scripts/snapshots/typesFiles.txt (1)

142-142: LGTM! Type declarations snapshot updated for new combiner module.

The addition correctly reflects the type declaration file for the new combiner module.

src/state/selectors/polarScaleSelectors.ts (1)

9-9: LGTM! Import updated as part of selector renaming refactor.

The change from selectAxisSettings to selectRenderableAxisSettings aligns with the broader refactoring across the codebase to use more descriptive selector names.

Also applies to: 75-75

src/state/selectors/rootPropsSelectors.ts (1)

7-7: Confirm the return type correctly excludes undefined.

The barGap property is defined in UpdatableChartOptions as number | string (never optional), initialized with default value 4 in initialState, and protected by nullish coalescing in reducers. The selector's return type string | number is correct.

src/state/selectors/containerSelectors.ts (1)

10-10: No action required. The margin property in ChartLayoutState is always initialized with a default value ({ top: 5, right: 5, bottom: 5, left: 5 }) in the initial state, and the setMargin reducer only mutates individual properties—it never assigns undefined or null to margin. The return type Margin (non-nullable) is correct and safe.

Likely an incorrect or invalid review comment.

test/chart/RadialBarChart.5966.spec.tsx (1)

41-41: LGTM - Selector signature simplified.

The call to selectRadiusAxisTicks has been correctly updated to match the simplified signature shown in the relevant code snippets, removing the third and fourth parameters.

test/cartesian/YAxis/YAxis.spec.tsx (1)

27-27: LGTM - Selector renamed to selectRenderableAxisSettings.

The update from selectAxisSettings to selectRenderableAxisSettings is consistent with the project-wide refactor to use more descriptive naming for renderable axis configuration.

Also applies to: 959-959, 1024-1025

test/cartesian/XAxis/XAxis.vertical.spec.tsx (1)

6-6: LGTM - Consistent selector rename.

The change from selectAxisSettings to selectRenderableAxisSettings aligns with the refactoring in other test files.

Also applies to: 166-166

test/polar/RadialBar.spec.tsx (1)

189-189: LGTM - Selector parameter simplified.

The removal of the last boolean parameter from selectBandSizeOfPolarAxis simplifies the API while maintaining the same test expectations.

test/cartesian/XAxis/XAxis.state.spec.tsx (1)

7-11: LGTM - Selector renamed consistently.

The updates to use selectRenderableAxisSettings are consistent with the project-wide refactoring of axis selector naming.

Also applies to: 20-20, 84-85

src/state/selectors/combiners/combineBarPosition.ts (1)

1-20: LGTM - Proper undefined checks implemented.

The new combineBarPosition function correctly:

• Uses == null to check for both null and undefined inputs (line 9)
• Returns undefined early when inputs are missing
• Returns undefined when no matching position is found (lines 16-18)
• Properly matches bar positions by stackId and dataKey

This aligns well with the PR's goal of adding more undefined checks.

test/cartesian/YAxis/YAxis.ticks.spec.tsx (1)

10-10: LGTM - Selector consistently renamed.

All usages of the axis settings selector have been properly updated to use selectRenderableAxisSettings, maintaining consistency with the broader refactoring.

Also applies to: 63-63, 117-117, 174-174, 229-229

src/state/selectors/polarSelectors.ts (2)

159-159: LGTM - Updated to use renderable axis settings.

The change to use selectRenderableAxisSettings instead of selectBaseAxis aligns with the project-wide refactoring and likely provides better type information for tick generation.

---

62-62: No action needed. The return type change from ChartData | undefined to ChartData is correct. The combineDisplayedData function already declares its return type as ChartData and all code paths return a ChartData value: either graphicalItemsData directly or the result of chartData.slice(), which always returns an array (never undefined).

src/state/selectors/combiners/combineAllBarPositions.ts (2)

26-26: LGTM!

Optional chaining on sizeList[0]?.barSize prevents potential runtime errors when the array is non-empty but the first element might be undefined or nullish.

---

55-57: Good fix for position tracking.

Assigning prev = newPosition.position correctly ensures the accumulator reflects the actual computed position for the next iteration, rather than using a stale reference.

src/state/selectors/combiners/combineBarSizeList.ts (4)

7-18: LGTM!

Type widening to string | number | undefined for globalSize properly supports percentage-based bar sizes.

---

30-38: Cleaner null-safe grouping logic.

The refactored approach with explicit null check and temporary variable is more defensive and handles missing stack arrays correctly.

---

40-44: LGTM!

Optional chaining on bars[0]?.barSize safely handles edge cases where a stack group might have an empty or sparse array.

---

64-64: Pre-existing any type in DataKey<any>.

The DataKey<any> type appears to be a pre-existing pattern in the codebase. While coding guidelines discourage any, this is likely inherited from the type definition rather than introduced in this PR.

src/state/selectors/barSelectors.ts (5)

29-29: LGTM!

Importing combineBarPosition centralizes bar position logic and reduces code duplication.

---

109-110: LGTM!

Return type tightened to always return SizeList, which is appropriate since combineBarSizeList always returns an array (possibly empty).

---

233-236: Good refactor to use centralized combiner.

Delegating to combineBarPosition improves maintainability and ensures consistent bar position logic across cartesian and polar charts.

---

268-295: LGTM!

Parameter types correctly widened to accept undefined for axes and barSettings, with comprehensive guard at lines 283-294 that short-circuits with undefined when any required value is missing.

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112-139: Function correctly ensures number return type with no undefined fallback paths.

The function selectBarBandSize is newly added and has a return type of number, not number | undefined. The implementation guarantees a number is always returned through early returns of 0 (lines 119, 124) and the final nullish coalescing chain (?? maxBarSize ?? 0 at line 138).

src/state/selectors/radialBarSelectors.ts (8)

38-38: LGTM!

Consistent import of combineBarPosition for centralized bar position logic in polar charts.

---

59-64: LGTM!

Simplified signature and hardcoding isPanorama to false is correct since radial bar charts do not support panorama mode.

---

92-99: LGTM!

The comment at line 97 clearly documents the rationale for hardcoding isPanorama to false.

---

238-241: LGTM!

Return type tightened to always return SizeList, consistent with cartesian bar selector changes.

---

249-274: LGTM!

Return type changed to number with proper fallbacks to 0 via ?? maxBarSize ?? 0 at lines 270, 272. Parameter types widened to accept undefined for axis-related inputs.

---

301-304: Good refactor to use centralized combiner.

Consistent with the cartesian bar position selector, using combineBarPosition ensures unified bar position logic.

---

359-408: LGTM!

Parameter types properly widened to accept undefined, with comprehensive guard at lines 396-406 that returns an empty array when any required value is missing. Added checks for radiusAxisTicks and polarViewBox improve null safety.

---

438-446: LGTM!

legendType parameter now accepts undefined, with the type propagated correctly through the selector chain.

src/state/selectors/axisSelectors.ts (8)

253-274: LGTM!

Renaming from selectAxisSettings to selectRenderableAxisSettings improves clarity by indicating this selector returns settings for axes that can be rendered (excluding ZAxis).

---

560-564: LGTM!

Using selectRenderableAxisSettings for tooltip axis is consistent with the renamed selector.

---

1088-1090: LGTM!

Narrowing the return type to D3ScaleType improves type safety by ensuring only valid D3 scale names are returned.

---

1092-1141: LGTM!

Return type changed to D3ScaleType | undefined throughout the scale type selection chain, improving type precision.

---

1197-1197: LGTM!

Consistent use of selectRenderableAxisSettings for nice ticks computation.

---

1220-1224: Good defensive fallback for empty tick arrays.

Adding ?? 0 ensures that if niceTicks[0] or niceTicks[niceTicks.length - 1] is undefined (e.g., empty array edge case after length check), the computation still produces valid bounds.

---

1836-1845: LGTM!

Type updates to use D3ScaleType | undefined for realScaleType and ReadonlyArray<unknown> for categoricalDomain improve flexibility while maintaining type safety through runtime checks.

Also applies to: 1888-1891, 1964-1971, 1986-1989

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1769-1771: LGTM!

Consistent use of selectRenderableAxisSettings across tick-related selectors maintains the refactored API surface.

Also applies to: 1943-1954, 2041-2051