Scoping dependencies, even in single entry point systems.

[nashysolutions]

Similar to how SwiftUI scopes light / dark mode change via a view modifier, could we do the same here, using the scoped dependencies API?

Something like this

import SwiftUI
import Dependencies

private struct ScopedDependencies<Content: View>: View {
    let modify: (inout DependencyValues) -> Void
    let content: Content

    init(
        modify: @escaping (inout DependencyValues) -> Void,
        @ViewBuilder content: () -> Content
    ) {
        self.modify = modify
        self.content = content()
    }

    var body: some View {
        withDependencies(modify, operation: { content })
    }
}

extension View {
    func overrideDependency<Value>(
        _ keyPath: WritableKeyPath<DependencyValues, Value>,
        with value: Value
    ) -> some View {
        ScopedDependencies(modify: {
            $0[keyPath: keyPath] = value
        }) {
            self
        }
    }
}

Usage

FeatureView()
    .overrideDependency(\.featureFlags, with: .init(isFeatureXEnabled: { true }))