Data source adapter, virtual data loader, TreeList data controller and data source adapter - type grid_core data source adapter and utils

[bit-byte0]

What

Added strict types to the grid_core data source adapter and its helper utilities, so m_data_source_adapter.ts and m_data_source_adapter_utils.ts pass the strict lint rules while keeping the m_ prefix

How

Annotated fields, parameters and return types and replaced loose any with real types, keeping the widely used public getters unchanged

[Copilot]

Copilot review overview

🟢 Approval recommended

The type-focused changes preserve existing control flow and remain consistent with related adapters and callers.

Review effort: Balanced
Findings: None

What changed in this PR

Adds strict typing to the grid-core data source adapter and cache utilities without changing public behavior.

Changes:

• Typed adapter state, handlers, and load operations.
• Typed cache, paging, and grouping helpers.
• Added grouped paging metadata to LoadOperation.

File	Description
types.ts	Adds grouped paging fields.
m_data_source_adapter.ts	Types adapter fields and methods.
m_data_source_adapter_utils.ts	Types cache and operation utilities.

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[Copilot]

Copilot review overview

🔵 Needs a closer look

The lastLoadOptions() return type incorrectly asserts required fields when returning an empty object.

Review effort: Balanced
Findings: None

Previously missed (1)

In code that hasn't changed since last review

Avoid asserting required pagination fields before initial load

packages/​devextreme/​js/​__internal/​grids/​grid_core/​data_source_adapter/​m_data_source_adapter.ts:823

This cast makes the getter claim that pageIndex and pageSize always exist, but before the first load _lastLoadOptions is undefined and this branch returns {}. That leaves callers with an unsound numeric contract. Return a partial shape here, matching data_source_controller.ts:182, instead of asserting required fields.

[anna-shakhova]

replace to unknown[] if we cannot properly type items right now

[anna-shakhova]

lets try get better type from usage

[anna-shakhova]

lets introduce variable for 1st part, it is difficult to read now

[Copilot]

Copilot review overview

🔵 Needs a closer look

The data-index getter incorrectly promises a number although uncached keys return undefined.

Review effort: Balanced
Findings: None

Previously missed (1)

In code that hasn't changed since last review

Allow data index getter to return undefined

packages/​devextreme/​js/​__internal/​grids/​grid_core/​data_source_adapter/​m_data_source_adapter.ts:330

The callback can return undefined when store.keyOf(data) is absent from _dataIndexByKey, but the new annotation promises a number. This hides a real result that sort consumers can receive. Please type _dataIndexGetter, this callback, and getDataIndexGetter() as returning number | undefined.

[Copilot]

Copilot review overview

🔵 Needs a closer look

Two new type contracts promise capabilities or defined results that their implementations do not guarantee.

Review effort: Balanced
Findings: None

Previously missed (2)

In code that hasn't changed since last review

Allow data index getter to return undefined

packages/​devextreme/​js/​__internal/​grids/​grid_core/​data_source_adapter/​m_data_source_adapter.ts:68

The getter can return undefined: when _cachedStoreData is unset or does not contain the requested key, the record lookup in getDataIndexGetter has no value. Declaring this callback as always returning number hides that valid outcome from callers. Please use number | undefined consistently in this field, getDataIndexGetter, and the delegating controller signature.

Narrow extension-point return type to key-info shape

packages/​devextreme/​js/​__internal/​grids/​grid_core/​data_source_adapter/​m_data_source_adapter.ts:351

This extension-point contract is broader than the object it actually guarantees. The TreeList override returns only key and keyOf (and currently has to cast that object to Store), while this method is consumed solely as applyBatch key information. Typing it as a full Store can let future callers invoke methods that are absent at runtime; narrow the return type to the key-info shape.