feat: adding default values

[mvhenten]

Example Usage
In TypeSpec:

model Task {
    description?: string = "No description provided";
    priority: Priority = Priority.MEDIUM;
    count: int32 = 0;
    active: boolean = true;
}

Generates ElectroDB schema:

{
    description: { type: "string", required: false, default: "No description provided" },
    priority: { type: ["LOW", "MEDIUM", "HIGH"], required: true, default: "MEDIUM" },
    count: { type: "number", required: true, default: 0 },
    active: { type: "boolean", required: true, default: true }
}

[github-actions]

🎉 This PR is included in version 3.1.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[Copilot]

Pull request overview

This PR adds support for default values in TypeSpec model properties, enabling developers to specify default values for string, number, boolean, and enum types in their entity definitions.

Key Changes:

• Added extractDefaultValue function to convert TypeSpec Value types to primitive JavaScript values
• Modified emitModelProperty and emitAttribute to include default values in the generated ElectroDB entity schemas
• Added comprehensive test coverage for default values across different data types (strings, numbers, booleans, enums) and nested models

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
test/main.tsp	Defines new Task entity model and Priority enum with various default values to test the feature, including optional and required properties with defaults, nested models with defaults, and different data types
test/entities.test.js	Adds comprehensive test suite for Task entity covering default values for all supported types (string, number, boolean, enum) and nested model properties. Also includes minor formatting improvements to existing tests
src/emitter.ts	Implements core functionality: adds extractDefaultValue helper function to extract default values from TypeSpec Value types, and updates both emitModelProperty and emitAttribute functions to include default values in generated attributes

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[Copilot]

The logic for adding default values is duplicated between emitModelProperty (lines 257-264) and emitAttribute (lines 312-319). Consider refactoring to avoid duplication. Since emitAttribute calls emitType which may eventually call emitModelProperty for nested models, you could rely on emitModelProperty to handle default values for nested properties and only handle them once in emitAttribute for top-level properties.

Suggested change

	// Add default value if present
	if (prop.defaultValue) {
	const defaultValue = extractDefaultValue(prop.defaultValue);
	if (defaultValue !== undefined) {
	// @ts-expect-error - default is a valid ElectroDB attribute property
	attr.default = defaultValue;
	}
	}