ethers.js/lib.commonjs/utils/utf8.d.ts
2023-04-27 21:19:55 +09:00

96 lines
3.9 KiB
TypeScript

import type { BytesLike } from "./index.js";
/**
* The stanard normalization forms.
*/
export type UnicodeNormalizationForm = "NFC" | "NFD" | "NFKC" | "NFKD";
/**
* When using the UTF-8 error API the following errors can be intercepted
* and processed as the %%reason%% passed to the [[Utf8ErrorFunc]].
*
* **``"UNEXPECTED_CONTINUE"``** - a continuation byte was present where there
* was nothing to continue.
*
* **``"BAD_PREFIX"``** - an invalid (non-continuation) byte to start a
* UTF-8 codepoint was found.
*
* **``"OVERRUN"``** - the string is too short to process the expected
* codepoint length.
*
* **``"MISSING_CONTINUE"``** - a missing continuation byte was expected but
* not found. The %%offset%% indicates the index the continuation byte
* was expected at.
*
* **``"OUT_OF_RANGE"``** - the computed code point is outside the range
* for UTF-8. The %%badCodepoint%% indicates the computed codepoint, which was
* outside the valid UTF-8 range.
*
* **``"UTF16_SURROGATE"``** - the UTF-8 strings contained a UTF-16 surrogate
* pair. The %%badCodepoint%% is the computed codepoint, which was inside the
* UTF-16 surrogate range.
*
* **``"OVERLONG"``** - the string is an overlong representation. The
* %%badCodepoint%% indicates the computed codepoint, which has already
* been bounds checked.
*
*
* @returns string
*/
export type Utf8ErrorReason = "UNEXPECTED_CONTINUE" | "BAD_PREFIX" | "OVERRUN" | "MISSING_CONTINUE" | "OUT_OF_RANGE" | "UTF16_SURROGATE" | "OVERLONG";
/**
* A callback that can be used with [[toUtf8String]] to analysis or
* recovery from invalid UTF-8 data.
*
* Parsing UTF-8 data is done through a simple Finite-State Machine (FSM)
* which calls the ``Utf8ErrorFunc`` if a fault is detected.
*
* The %%reason%% indicates where in the FSM execution the fault
* occurred and the %%offset%% indicates where the input failed.
*
* The %%bytes%% represents the raw UTF-8 data that was provided and
* %%output%% is the current array of UTF-8 code-points, which may
* be updated by the ``Utf8ErrorFunc``.
*
* The value of the %%badCodepoint%% depends on the %%reason%%. See
* [[Utf8ErrorReason]] for details.
*
* The function should return the number of bytes that should be skipped
* when control resumes to the FSM.
*/
export type Utf8ErrorFunc = (reason: Utf8ErrorReason, offset: number, bytes: Uint8Array, output: Array<number>, badCodepoint?: number) => number;
/**
* A handful of popular, built-in UTF-8 error handling strategies.
*
* **``"error"``** - throws on ANY illegal UTF-8 sequence or
* non-canonical (overlong) codepoints (this is the default)
*
* **``"ignore"``** - silently drops any illegal UTF-8 sequence
* and accepts non-canonical (overlong) codepoints
*
* **``"replace"``** - replace any illegal UTF-8 sequence with the
* UTF-8 replacement character (i.e. ``"\\ufffd"``) and accepts
* non-canonical (overlong) codepoints
*
* @returns: Record<"error" | "ignore" | "replace", Utf8ErrorFunc>
*/
export declare const Utf8ErrorFuncs: Readonly<Record<"error" | "ignore" | "replace", Utf8ErrorFunc>>;
/**
* Returns the UTF-8 byte representation of %%str%%.
*
* If %%form%% is specified, the string is normalized.
*/
export declare function toUtf8Bytes(str: string, form?: UnicodeNormalizationForm): Uint8Array;
/**
* Returns the string represented by the UTF-8 data %%bytes%%.
*
* When %%onError%% function is specified, it is called on UTF-8
* errors allowing recovery using the [[Utf8ErrorFunc]] API.
* (default: [error](Utf8ErrorFuncs))
*/
export declare function toUtf8String(bytes: BytesLike, onError?: Utf8ErrorFunc): string;
/**
* Returns the UTF-8 code-points for %%str%%.
*
* If %%form%% is specified, the string is normalized.
*/
export declare function toUtf8CodePoints(str: string, form?: UnicodeNormalizationForm): Array<number>;
//# sourceMappingURL=utf8.d.ts.map