Update Package.swift to add EnvManager support

Author: Kyle-Ye

Package.resolved

@@ -1,58 +1,156 @@
 // swift-tools-version: 6.1
-// The swift-tools-version declares the minimum version of Swift required to build this package.
 
+import CompilerPluginSupport
+import Foundation
 import PackageDescription
 
-func envEnable(_ key: String, default defaultValue: Bool = false) -> Bool {
-    guard let value = Context.environment[key] else {
-        return defaultValue
+// MARK: - EnvManager
+
+/* GENERATED BY SPMManifestTool BEGIN */
+/* DO NOT EDIT */
+
+public protocol EnvironmentProvider {
+    func value(forKey key: String) -> String?
+}
+
+import PackageDescription
+public struct PackageContextEnvironmentProvider: EnvironmentProvider {
+    public init() {}
+
+    public func value(forKey key: String) -> String? {
+        Context.environment[key]
+    }
+}
+
+public final class EnvManager {
+    nonisolated(unsafe) public static let shared = EnvManager()
+
+    private var domains: [String] = []
+    private var environmentProvider: EnvironmentProvider
+
+    /// When true, append raw key as fallback when searching in domains
+    public var includeFallbackToRawKey: Bool = false
+
+    private init() {
+        self.environmentProvider = PackageContextEnvironmentProvider()
+    }
+
+    /// Set a custom environment provider (useful for testing)
+    public func setEnvironmentProvider(_ provider: EnvironmentProvider) {
+        self.environmentProvider = provider
+    }
+
+    /// Reset domains and environment provider (useful for testing)
+    public func reset() {
+        domains.removeAll()
+        includeFallbackToRawKey = false
+        self.environmentProvider = PackageContextEnvironmentProvider()
+    }
+
+    public func register(domain: String) {
+        domains.append(domain)
+    }
+
+    public func withDomain<T>(_ domain: String, perform: () throws -> T) rethrows -> T {
+        domains.append(domain)
+        defer { domains.removeAll { $0 == domain } }
+        return try perform()
     }
-    if value == "1" {
-        return true
-    } else if value == "0" {
-        return false
-    } else {
+
+    private func envValue<T>(rawKey: String, default defaultValue: T?, searchInDomain: Bool, parser: (String) -> T?) -> T? {
+        func parseEnvValue(_ key: String) -> (String, T)? {
+            guard let value = environmentProvider.value(forKey: key),
+                  let result = parser(value) else { return nil }
+            return (value, result)
+        }
+        var keys: [String] = searchInDomain ? domains.map { "\($0.uppercased())_\(rawKey)" } : []
+        if !searchInDomain || includeFallbackToRawKey {
+            keys.append(rawKey)
+        }
+        for key in keys {
+            if let (value, result) = parseEnvValue(key) {
+                print("[Env] \(key)=\(value) -> \(result)")
+                return result
+            }
+        }
+        let primaryKey = keys.first ?? rawKey
+        if let defaultValue {
+            print("[Env] \(primaryKey) not set -> \(defaultValue)(default)")
+        }
         return defaultValue
     }
+
+    public func envBoolValue(rawKey: String, default defaultValue: Bool? = nil, searchInDomain: Bool) -> Bool? {
+        envValue(rawKey: rawKey, default: defaultValue, searchInDomain: searchInDomain) { value in
+            switch value {
+            case "1": true
+            case "0": false
+            default: nil
+            }
+        }
+    }
+
+    public func envIntValue(rawKey: String, default defaultValue: Int? = nil, searchInDomain: Bool) -> Int? {
+        envValue(rawKey: rawKey, default: defaultValue, searchInDomain: searchInDomain) { Int($0) }
+    }
+
+    public func envStringValue(rawKey: String, default defaultValue: String? = nil, searchInDomain: Bool) -> String? {
+        envValue(rawKey: rawKey, default: defaultValue, searchInDomain: searchInDomain) { $0 }
+    }
 }
 
-var sharedSwiftSettings: [SwiftSetting] = [
-    .swiftLanguageMode(.v6),
-    .enableUpcomingFeature("InternalImportsByDefault"),
-]
+public func envBoolValue(_ key: String, default defaultValue: Bool = false, searchInDomain: Bool = true) -> Bool {
+    EnvManager.shared.envBoolValue(rawKey: key, default: defaultValue, searchInDomain: searchInDomain)!
+}
+
+public func envIntValue(_ key: String, default defaultValue: Int = 0, searchInDomain: Bool = true) -> Int {
+    EnvManager.shared.envIntValue(rawKey: key, default: defaultValue, searchInDomain: searchInDomain)!
+}
+
+public func envStringValue(_ key: String, default defaultValue: String, searchInDomain: Bool = true) -> String {
+    EnvManager.shared.envStringValue(rawKey: key, default: defaultValue, searchInDomain: searchInDomain)!
+}
+
+public func envStringValue(_ key: String, searchInDomain: Bool = true) -> String? {
+    EnvManager.shared.envStringValue(rawKey: key, searchInDomain: searchInDomain)
+}
+
+/* GENERATED BY SPMManifestTool END */
+EnvManager.shared.register(domain: "OpenCoreGraphics")
+EnvManager.shared.register(domain: "OpenSwiftUI")
+
+// MARK: - Env and config
 
 #if os(macOS)
 // NOTE: #if os(macOS) check is not accurate if we are cross compiling for Linux platform. So we add an env key to specify it.
-let buildForDarwinPlatform = envEnable("OPENCOREGRAPHICS_BUILD_FOR_DARWIN_PLATFORM", default: true)
+let buildForDarwinPlatform = envBoolValue("BUILD_FOR_DARWIN_PLATFORM", default: true)
 #else
-let buildForDarwinPlatform = envEnable("OPENCOREGRAPHICS_BUILD_FOR_DARWIN_PLATFORM")
+let buildForDarwinPlatform = envBoolValue("BUILD_FOR_DARWIN_PLATFORM")
 #endif
 
 let isXcodeEnv = Context.environment["__CFBundleIdentifier"] == "com.apple.dt.Xcode"
+let development = envBoolValue("DEVELOPMENT")
 
-let development = envEnable("OPENCOREGRAPHICS_DEVELOPMENT")
+let coreGraphicsCondition = envBoolValue("COREGRAPHICS", default: buildForDarwinPlatform)
+let warningsAsErrorsCondition = envBoolValue("WERROR", default: isXcodeEnv && development)
+let libraryEvolutionCondition = envBoolValue("LIBRARY_EVOLUTION", default: buildForDarwinPlatform)
 
-// MARK: - [env] OPENCOREGRAPHICS_COREGRAPHICS
+var sharedSwiftSettings: [SwiftSetting] = [
+    .swiftLanguageMode(.v6),
+    .enableUpcomingFeature("InternalImportsByDefault"),
+]
 
-let coreGraphicsCondition = envEnable("OPENCOREGRAPHICS_COREGRAPHICS", default: buildForDarwinPlatform)
 if coreGraphicsCondition {
-    sharedSwiftSettings.append(.define("OPENCOREGRAPHICS_COREGRAPHICS"))
+    sharedSwiftSettings.append(.define("COREGRAPHICS"))
 }
 
-// MARK: - [env] OPENCOREGRAPHICS_WERROR
-
-let warningsAsErrorsCondition = envEnable("OPENCOREGRAPHICS_WERROR", default: isXcodeEnv && development)
 if warningsAsErrorsCondition {
     sharedSwiftSettings.append(.unsafeFlags(["-warnings-as-errors"]))
 }
 
-// MARK: - [env] OPENCOREGRAPHICS_LIBRARY_EVOLUTION
-
-let libraryEvolutionCondition = envEnable("OPENCOREGRAPHICS_LIBRARY_EVOLUTION", default: buildForDarwinPlatform)
-
 if libraryEvolutionCondition {
     // NOTE: -enable-library-evolution will cause module verify failure for `swift build`.
-    // Either set OPENCOREGRAPHICS_LIBRARY_EVOLUTION=0 or add `-Xswiftc -no-verify-emitted-module-interface` after `swift build`
+    // Either set LIBRARY_EVOLUTION=0 or add `-Xswiftc -no-verify-emitted-module-interface` after `swift build`
     sharedSwiftSettings.append(.unsafeFlags(["-enable-library-evolution", "-no-verify-emitted-module-interface"]))
 }