SwiftUI: Peek at/extract hidden environment values

_Example.swift

// expose hidden environment members like so:
extension EnvironmentValues {
    public var foregroundColor: Color? { value(forKey: "ForegroundColorKey") }
    public var accentColor: Color? { value(forKey: "AccentColorKey") }
}

// then you can use them like any others:
@Environment(\.foregroundColor) var foregroundColor

// You can see all the available values with something like:
@Environment(\.dumpEnvironment) var dump
//Then
let _ = dump

EnvironmentValues.swift

import Foundation
import SwiftUI

extension EnvironmentValues {
    public func value<T>(_: T.Type = T.self, forKey key: String) -> T? {
        guard let value = first(where: { name($0, equals: key) }) else {
            print("No EnvironmentValue with key '\(key)' found.")
            return nil
        }

        let valueMirror = Mirror(reflecting: value)
        let environmentValue = valueMirror.descendant("value", "some")
        if let result = environmentValue as? T {
            return result
        } else if let value = valueMirror.children.first?.value, let result = value as? T {
            return result
        } else {
            print("EnvironmentValue with key '\(key)' mismatch. Expected \(T.self), found \(type(of: environmentValue))")
            return nil
        }
    }

    private func name(_ value: Any, equals key: String) -> Bool {
        let parts = String(describing: type(of: value)).components(separatedBy: .init(charactersIn: "<>"))
        return parts.contains(key)
    }
}

extension EnvironmentValues: Sequence {
    public func makeIterator() -> AnyIterator<Any> {
        let mirror = Mirror(reflecting: self)

        guard let plist = mirror.children.first(where: { $0.label?.contains("plist") ?? false })?.label else {
            print("Unable to find EnvironmentValue elements from", mirror.children.map(\.label))
            return .init { nil }
        }

        var current = mirror.descendant(plist, "elements", "some")

        return .init {
            guard let value = current else { return nil }

            defer {
                let next = Mirror(reflecting: value).superclassMirror
                current = next?.descendant("after", "some")
            }

            return value
        }
    }
}

extension EnvironmentValues {
    public var dumpEnvironment: Bool {
        self.forEach { print($0) }
        return true
    }
}

extension Mirror {
    public func dump(indent: Int = 0) {
        let i = String(repeating: " ", count: indent)

        for item in children {
            print(i, "\(item.label ?? "<none>"):\(type(of: item.value))", item.value as Any)
            let mirror = Mirror(reflecting: item.value)
            if let m = mirror.superclassMirror {
                m.dump(indent: indent + 1)
            } else {
                mirror.dump(indent: indent + 1)
            }
        }
    }
}