Spectrum Diff Core

Shared core library for Spectrum diff generation tools (tokens, component schemas, etc.).

Overview

This package provides the foundational components for creating consistent diff tools across the Spectrum ecosystem. It includes:

• Core utilities: File import/export, diff operations, type checking
• CLI framework: Base CLI structure with consistent option handling
• Template system: Handlebars-based formatting with shared helpers
• Output handling: File output and console formatting

Installation

pnpm add @adobe/spectrum-diff-core

Usage

Creating a Diff Tool

import { BaseCLI, FileLoader, detailedDiff } from "@adobe/spectrum-diff-core";

class MyDiffTool extends BaseCLI {
  constructor() {
    super({
      toolName: "mydiff",
      dataType: "mydata",
      packagePath: "packages/mydata/src",
      manifestFile: "manifest.json",
    });
  }

  async generateDiff(original, updated) {
    const changes = detailedDiff(original, updated);
    // Add your specific change detection logic here
    return this.processChanges(changes);
  }
}

Using File Loading

import { FileLoader } from "@adobe/spectrum-diff-core";

const loader = new FileLoader();

// Load from remote repository
const remoteData = await loader.loadRemoteFiles(
  ["file1.json", "file2.json"],
  "v1.0.0",
  null,
  "owner/repo",
  "api-key",
  "packages/data/src",
);

// Load from local filesystem
const localData = await loader.loadLocalFiles("packages/data/src", [
  "file1.json",
  "file2.json",
]);

Using Templates

import { HandlebarsFormatter } from "@adobe/spectrum-diff-core";

const formatter = new HandlebarsFormatter({
  template: "cli",
  dataType: "tokens",
});

const output = await formatter.format(diffResult, options);

CLI Framework

The BaseCLI class provides a consistent CLI structure:

mydiff report --old-version v1.0.0 --new-version v1.1.0 --format markdown --output report.md

Common CLI Options:

• --old-[type]-version / --new-[type]-version (version comparison)
• --old-[type]-branch / --new-[type]-branch (branch comparison)
• --local (local file comparison)
• --format (cli, markdown, handlebars)
• --template (built-in template names)
• --output (file output)
• --debug (debug output)

Template System

Templates are organized by data type:

templates/
├── base/           # Shared templates
│   ├── cli.hbs
│   ├── markdown.hbs
│   └── json.hbs
├── tokens/         # Token-specific templates
└── schemas/        # Schema-specific templates

Available Helpers

• {{hasKeys obj}} - Check if object has properties
• {{totalItems result}} - Calculate total number of changes
• {{capitalize str}} - Capitalize string
• {{cleanPath path}} - Clean up property paths
• {{formatDate date}} - Format timestamps
• {{hilite}}, {{error}}, {{passing}} - Terminal colors
• {{bold}}, {{dim}}, {{emphasis}} - Text formatting

API Reference

Core

• detailedDiff(original, updated) - Generate detailed diff
• isObject(obj), isString(str), etc. - Type checking utilities
• deepClone(obj) - Deep clone objects
• getNestedProperty(obj, path) - Safe property access

File Import

• FileLoader - Main file loading orchestrator
• RemoteFileFetcher - Handle remote repository fetching
• LocalFileSystem - Handle local file operations

CLI

• BaseCLI - Base class for creating CLI tools
• normalizeOptions(options) - Normalize CLI options
• determineStrategy(options) - Determine loading strategy

Formatters

• HandlebarsFormatter - Template-based formatting
• storeOutput(content, path) - File output utility

Development

# Install dependencies
pnpm install

# Run tests
pnpm test

# Lint code
pnpm lint

# Fix linting issues
pnpm lint:fix

License

Apache-2.0