src — encoding

Module: src-encoding Cohesion: 0.80 Members: 0

src — encoding

The src/encoding module provides a comprehensive suite of utilities for handling various aspects of text and data encoding, decoding, character set management, and format conversions. It aims to centralize common encoding-related operations, ensuring consistency and robustness across the application.

Module Structure

The encoding module is organized into three primary sub-modules, all re-exported through src/encoding/index.ts for a unified public API. 

graph TD
    A[src/encoding/index.ts] --> B(src/encoding/text-encoder.ts)
    A --> C(src/encoding/charset-handler.ts)
    A --> D(src/encoding/format-converter.ts)
    C -- uses EncodingError --> B
    D -- uses EncodingError --> B

Core Concepts

EncodingError

All functions within the encoding module throw instances of EncodingError when encountering invalid input, unsupported formats, or conversion failures. This custom error class, defined in text-encoder.ts, allows for specific error handling related to encoding operations. 

export class EncodingError extends Error {
  constructor(message: string) {
    super(message);
    this.name = 'EncodingError';
  }
}

Character Set Names

The charset-handler.ts module defines a CharsetName type to standardize the character sets supported for detection and conversion: 

export type CharsetName = 'utf-8' | 'utf-16' | 'utf-16le' | 'utf-16be' | 'ascii' | 'latin1' | 'iso-8859-1';

Sub-modules in Detail

text-encoder.ts — Text Encoding and Decoding Primitives

This sub-module provides foundational utilities for converting strings to and from various common encoding formats. It leverages native browser/Node.js APIs like TextEncoder, TextDecoder, btoa, and atob where appropriate.

Key Functions:

charset-handler.ts — Character Set and Line Ending Utilities

This sub-module provides tools for identifying, validating, and manipulating character sets and line endings within text data.

Key Functions:

format-converter.ts — Structured Data Format Conversions

This sub-module provides utilities for converting between common structured data formats, facilitating interoperability.

Key Functions:

Error Handling

All public functions in the encoding module perform input validation and throw an EncodingError if inputs are null, undefined, of the wrong type, or if the content is malformed for the intended operation (e.g., invalid Base64 string, non-ASCII characters for ASCII encoding). Developers should wrap calls to these functions in try...catch blocks to handle potential encoding-related issues gracefully.

Integration Points

The encoding module is designed to be a foundational utility layer.

Internal Usage:

External Usage:

Note on Call Graph Interpretation: The provided call graph indicates some "outgoing calls" to test and padStart from within src/encoding. These are not calls to external modules but rather invocations of built-in JavaScript methods:

These are standard language features and do not represent dependencies on other application modules.

Contributing

When contributing to the src/encoding module:

  1. Consistency: Adhere to the existing patterns for input validation and error handling, consistently throwing EncodingError for invalid operations.
  2. Performance: Be mindful of performance, especially for functions processing large strings or byte arrays. Leverage native APIs (TextEncoder, TextDecoder, btoa, atob) where appropriate.
  3. Robustness: Ensure new functions handle edge cases (empty inputs, malformed data, boundary conditions) gracefully.
  4. Test Coverage: All new functions and significant changes must be accompanied by comprehensive unit tests in tests/unit/encoding.test.ts.
  5. Clarity: Keep function signatures and documentation clear, explaining expected inputs, outputs, and potential errors.
  6. Charset Handling: When dealing with character sets, be explicit about the encoding used and consider Unicode compatibility. Avoid assumptions about default encodings.