SwiftUI code generation template for SwiftGen

SwiftUI code generation template for SwiftGen.md

Example of generated code

internal extension Color {
  // Assets.xcassets
  static var midnightBlue : Color { Color("midnightBlue", bundle: BundleToken.bundle) }
}

internal extension Image {
// Assets.xcassets
  static var abc : Color { Image("abc", bundle: BundleToken.bundle) }
}

Usage

  Color.midnightBlue // Color
  Image.abc // Image

swiftui-xcassets.stencil

// swiftlint:disable all
// Generated using SwiftGen — https://github.com/SwiftGen/SwiftGen

{% if catalogs %}
{% set forceNamespaces %}{{param.forceProvidesNamespaces|default:"false"}}{% endset %}
{% set accessModifier %}{% if param.publicAccess %}public{% else %}internal{% endif %}{% endset %}
import SwiftUI

{% macro casesBlock assets type prefix %}
  {% for asset in assets %}
  {% if asset.type == type %}
  static var {% if prefix %}{{prefix}}{% endif %}{{asset.name|swiftIdentifier:"pretty"|lowerFirstWord|escapeReservedKeywords}} : {{type|capitalize}} { {{type|capitalize}}("{{asset.value}}", bundle: BundleToken.bundle) }
  {% elif asset.items and ( forceNamespaces == "true" or asset.isNamespaced == "true" ) %}
    {% set prefixed_asset %}{% if prefix == "" %}{{asset.name|lowerFirstWord|swiftIdentifier:"pretty"}}_{% else %}{{prefix}}{{asset.name|lowerFirstWord|swiftIdentifier:"pretty"}}_{% endif %}{% endset %}
    {% call casesBlock asset.items type prefixed_asset %}
  {% elif asset.items %}
  {% call casesBlock asset.items type prefix %}
  {% endif %}
  {% endfor %}
{% endmacro %}
{{accessModifier}} extension Color {
  {% if catalogs.count > 1 %}
  {% for catalog in catalogs %}
  // {{catalog.name}}.xcassets
    {% set prefixed_catalog %}{{catalog.name|swiftIdentifier:"pretty"|lowerFirstWord}}_{% endset %}
    {% if forceNamespaces == "true" %} {% call casesBlock catalog.assets "color" prefixed_catalog %}{% else %}{% call casesBlock catalog.assets "color" "" %}{% endif %}
  {% endfor %}
  {% else %}
  // {{catalogs.first.name}}.xcassets
  {% set prefixed_catalog %}{{catalogs.first.name|swiftIdentifier:"pretty"|lowerFirstWord}}_{% endset %}
  {% if forceNamespaces == "true" %} {% call casesBlock catalogs.first.assets "color" prefixed_catalog %}{% else %}{% call casesBlock catalogs.first.assets "color" "" %}{% endif %}
  {% endif %}
}

{{accessModifier}} extension Image {
  {% if catalogs.count > 1 %}
  {% for catalog in catalogs %}
  // {{catalog.name}}.xcassets
    {% set prefixed_catalog %}{{catalog.name|swiftIdentifier:"pretty"|lowerFirstWord}}_{% endset %}
    {% if forceNamespaces == "true" %} {% call casesBlock catalog.assets "image" prefixed_catalog %}{% else %}{% call casesBlock catalog.assets "image" "" %}{% endif %}
  {% endfor %}
  {% else %}
  // {{catalogs.first.name}}.xcassets
  {% set prefixed_catalog %}{{catalogs.first.name|swiftIdentifier:"pretty"|lowerFirstWord}}_{% endset %}
  {% if forceNamespaces == "true" %} {% call casesBlock catalogs.first.assets "image" prefixed_catalog %}{% else %}{% call casesBlock catalogs.first.assets "image" "" %}{% endif %}
  {% endif %}
}

{% if resourceCount.image > 0 %}
{% endif %}
private final class BundleToken {
  static let bundle: Bundle = {
    Bundle(for: BundleToken.self)
  }()
}
{% else %}
// No assets found
{% endif %}

Nice, thanks for this!
Note I found this causes issues when I name a colour in my xcassets file with a standard name (e.g. "Red") as this tries to create Color.red - which already exists. In my usage I made a slight change to the stencil to produce a local struct called something like AppColor, rather than extending the Color struct.

(That is I use the enumName value like {{accessModifier}} struct {{enumName}})

@MeteC this can work, sure. Alternatively you can rename your red color to preserve the Color.name syntax.

One more nice thing about extending Color and Image is getting type inference in places where it's applicable. For example:

Text("foo").foregroundColor(.carrot)

Not a major thing by any means, but still :)

Ah very good point! And you're right, it's not too hard to name custom colours a little more "custom-ly" than just "Red" 😅