src/TulsiGenerator/TulsiOptionSet.swift - tulsi - Git at Google

 // Copyright 2016 The Tulsi Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 import Foundation


 /// Keys for all user modifiable Tulsi options.
 // Style note: Entries that map directly to Xcode Build Settings values are all caps (matching
 // Xcode's use) while entries handled in Tulsi are camel case.
 public enum TulsiOptionKey: String {
   case
       // Whether or not to search user header paths first when resolving angle bracket includes.
       ALWAYS_SEARCH_USER_PATHS,

       // What C++ language standard to use for the project.
       CLANG_CXX_LANGUAGE_STANDARD,

       // The path to the Bazel binary.
       BazelPath,
       // Whether or not to claim Swift code was created at the same version as Tulsi itself.
       // Suppresses the Xcode warning and automated update on first opening of the generated
       // project.
       SuppressSwiftUpdateCheck,
       // Whether or not containing a Swift dependency forces dSYM generation (used for debugging).
       SwiftForcesdSYMs,
       // Whether or not to use tree artifact outputs. Should only be disabled if it causes errors.
       // Known issues:
       // - Bundles with spaces in the name
       TreeArtifactOutputs,
       // The path from a config file to its associated workspace root.
       WorkspaceRootPath,

       // Commandline Arguments used by the run phase of the generated scheme.
       CommandlineArguments,

       // Environment Variables used by the run phase of the generated scheme.
       EnvironmentVariables,

       // Option to enable compilation after error.
       BazelContinueBuildingAfterError,

       // Include all .bzl files related to the build in the generated Xcodeproj.
       IncludeBuildSources,

       // Compilation mode to use during project generation.
       ProjectGenerationCompilationMode,

       // Platform configuration to use during project generation.
       ProjectGenerationPlatformConfiguration,

       // Startup options for project generation.
       ProjectGenerationBazelStartupOptions,

       // Improve auto-completion for include/import statements.
       ImprovedImportAutocompletionFix,

       // Generate .runfiles directory, as referenced by TEST_SRCDIR in bazel tests.
       GenerateRunfiles,

       // Used by Tulsi to improve Bazel-caching of build flags.
       ProjectPrioritizesSwift,

       // Custom build phase run script that runs before bazel build.
       PreBuildPhaseRunScript,

       // Custom build phase run script that runs after bazel build.
       PostBuildPhaseRunScript

   // Options for build invocations.
   case BazelBuildOptionsDebug,
        BazelBuildOptionsRelease

   // Startup options for build invocations.
   case BazelBuildStartupOptionsDebug,
        BazelBuildStartupOptionsRelease

   // Pre action scripts for build, launch, and test actions.
   case BuildActionPreActionScript,
        LaunchActionPreActionScript,
        TestActionPreActionScript

   // Post action scripts for build, launch, and test actions.
   case BuildActionPostActionScript,
        LaunchActionPostActionScript,
        TestActionPostActionScript
 }


 /// Logical groupings for TulsiOptionKeys.
 public enum TulsiOptionKeyGroup: String {
   case BazelBuildOptions,
        BazelBuildStartupOptions,
        PreActionScriptOptions,
        PostActionScriptOptions
 }


 /// Models the set of all user-modifiable options supported by Tulsi.
 public class TulsiOptionSet: Equatable {
   /// Suffix added to string keys in order to resolve an option's description.
   static let DescriptionStringKeySuffix = "_DESC"

   /// The key under which option sets are serialized.
   static let PersistenceKey = "optionSet"

   typealias PersistenceType = [String: TulsiOption.PersistenceType]

   static let OptionKeyGroups: [TulsiOptionKey: TulsiOptionKeyGroup] = [
       .ProjectGenerationBazelStartupOptions: .BazelBuildStartupOptions,
       .BazelBuildOptionsDebug: .BazelBuildOptions,
       .BazelBuildOptionsRelease: .BazelBuildOptions,
       .BazelBuildStartupOptionsDebug: .BazelBuildStartupOptions,
       .BazelBuildStartupOptionsRelease: .BazelBuildStartupOptions,
       .BuildActionPreActionScript: .PreActionScriptOptions,
       .LaunchActionPreActionScript: .PreActionScriptOptions,
       .TestActionPreActionScript: .PreActionScriptOptions,
       .BuildActionPostActionScript: .PostActionScriptOptions,
       .LaunchActionPostActionScript: .PostActionScriptOptions,
       .TestActionPostActionScript: .PostActionScriptOptions
   ]

   public var allVisibleOptions = [TulsiOptionKey: TulsiOption]()
   var options = [TulsiOptionKey: TulsiOption]() {
     didSet {
       allVisibleOptions = [TulsiOptionKey: TulsiOption]()
       for (key, option) in options {
         if !option.optionType.contains(.Hidden) {
           allVisibleOptions[key] = option
         }
       }
     }
   }
   var optionKeyGroupInfo = [TulsiOptionKeyGroup: (displayName: String, description: String)]()

   public subscript(optionKey: TulsiOptionKey) -> TulsiOption {
     return options[optionKey]!
   }

   public subscript(optionKey: TulsiOptionKey, target: String) -> String? {
     return options[optionKey]?.valueForTarget(target)
   }

   static func getOptionsFromContainerDictionary(_ dict: [String: Any]) -> PersistenceType? {
     return dict[TulsiOptionSet.PersistenceKey] as? PersistenceType
   }

   public init(withInheritanceEnabled inherit: Bool = false) {
     let bundle = Bundle(for: type(of: self))
     populateOptionsWithBundle(bundle, withInheritAsDefault: inherit)
     populateOptionGroupInfoWithBundle(bundle)
   }

   public convenience init(fromDictionary dict: [String: Any]) {
     self.init()

     guard let persistedOptions = dict as? PersistenceType else {
       assertionFailure("Options dictionary is not of the expected type")
       return
     }

     for (key, option) in options {
       if let value = persistedOptions[key.rawValue] {
         option.deserialize(value)
       }
     }
   }

   /// Returns a new TulsiOptionSet by using the given parent as a base and applying this option
   /// set's options as overrides.
   public func optionSetByInheritingFrom(_ parent: TulsiOptionSet) -> TulsiOptionSet {
     var resolvedOptions = [TulsiOptionKey: TulsiOption]()
     for (key, opt) in options {
       guard let parentOption = parent.options[key] else {
         resolvedOptions[key] = opt
         continue
       }
       resolvedOptions[key] = TulsiOption(resolvingValuesFrom: opt, byInheritingFrom: parentOption)
     }

     let resolvedSet = TulsiOptionSet()
     resolvedSet.options = resolvedOptions
     return resolvedSet
   }

   func saveShareableOptionsIntoDictionary(_ dict: inout [String: Any]) {
     let serialized = saveToDictionary() {
       !$1.optionType.contains(.PerUserOnly)
     }
     dict[TulsiOptionSet.PersistenceKey] = serialized
   }

   func savePerUserOptionsIntoDictionary(_ dict: inout [String: Any]) {
     let serialized = saveToDictionary() {
       return $1.optionType.contains(.PerUserOnly)
     }
     dict[TulsiOptionSet.PersistenceKey] = serialized
   }

   func saveAllOptionsIntoDictionary(_ dict: inout [String: AnyObject]) {
     let serialized = saveToDictionary() { (_, _) in return true }
     dict[TulsiOptionSet.PersistenceKey] = serialized as AnyObject?
   }

   public func groupInfoForOptionKey(_ key: TulsiOptionKey) -> (TulsiOptionKeyGroup, displayName: String, description: String)? {
     guard let keyGroup = TulsiOptionSet.OptionKeyGroups[key] else { return nil }
     guard let (displayName, description) = optionKeyGroupInfo[keyGroup] else {
       assertionFailure("Missing group information for group key \(keyGroup)")
       return (keyGroup, "\(keyGroup)", "")
     }
     return (keyGroup, displayName, description)
   }

   /// Returns a dictionary of build settings without applying any specializations.
   func commonBuildSettings() -> [String: String] {
     // These values come from AppleToolchain.java in Bazel
     // https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java
     var buildSettings = [
         "GCC_WARN_64_TO_32_BIT_CONVERSION": "YES",
         "CLANG_WARN_BOOL_CONVERSION": "YES",
         "CLANG_WARN_CONSTANT_CONVERSION": "YES",
         "CLANG_WARN__DUPLICATE_METHOD_MATCH": "YES",
         "CLANG_WARN_EMPTY_BODY": "YES",
         "CLANG_WARN_ENUM_CONVERSION": "YES",
         "CLANG_WARN_INT_CONVERSION": "YES",
         "CLANG_WARN_UNREACHABLE_CODE": "YES",
         "GCC_WARN_ABOUT_RETURN_TYPE": "YES",
         "GCC_WARN_UNDECLARED_SELECTOR": "YES",
         "GCC_WARN_UNINITIALIZED_AUTOS": "YES",
         "GCC_WARN_UNUSED_FUNCTION": "YES",
         "GCC_WARN_UNUSED_VARIABLE": "YES",
     ]

     for (key, opt) in options.filter({ $1.optionType.contains(.BuildSetting) }) {
       buildSettings[key.rawValue] = opt.commonValue!
     }
     return buildSettings
   }

   /// Returns a dictionary of build settings specialized for the given target without inheriting any
   /// defaults.
   func buildSettingsForTarget(_ target: String) -> [String: String] {
     var buildSettings = [String: String]()
     for (key, opt) in options.filter({ $1.optionType.contains(.TargetSpecializableBuildSetting) }) {
       if let val = opt.valueForTarget(target, inherit: false) {
         buildSettings[key.rawValue] = val
       }
     }
     return buildSettings
   }

   // MARK: - Private methods.

   private func saveToDictionary(_ filter: (TulsiOptionKey, TulsiOption) -> Bool) -> PersistenceType {
     var serialized = PersistenceType()
     for (key, option) in options.filter(filter) {
       if let value = option.serialize() {
         serialized[key.rawValue] = value
       }
     }
     return serialized
   }

   private func populateOptionsWithBundle(_ bundle: Bundle, withInheritAsDefault inherit: Bool) {
     func addOption(_ optionKey: TulsiOptionKey, valueType: TulsiOption.ValueType, optionType: TulsiOption.OptionType, defaultValue: String?) {
       let key = optionKey.rawValue
       let displayName = bundle.localizedString(forKey: key, value: nil, table: "Options")
       let descriptionKey = key + TulsiOptionSet.DescriptionStringKeySuffix
       var description = bundle.localizedString(forKey: descriptionKey, value: nil, table: "Options")
       if description == descriptionKey { description = "" }

       let opt = TulsiOption(displayName: displayName,
                             userDescription: description,
                             valueType: valueType,
                             optionType: optionType,
                             defaultValue: defaultValue)
       if inherit && optionType.contains(.SupportsInheritKeyword) {
         opt.projectValue = TulsiOption.InheritKeyword
       }
       options[optionKey] = opt
     }

     func addBoolOption(_ optionKey: TulsiOptionKey, _ optionType: TulsiOption.OptionType, _ defaultValue: Bool = false) {
       let val = defaultValue ? TulsiOption.BooleanTrueValue : TulsiOption.BooleanFalseValue
       addOption(optionKey, valueType: .bool, optionType: optionType, defaultValue: val)
     }

     func addStringOption(_ optionKey: TulsiOptionKey, _ optionType: TulsiOption.OptionType, _ defaultValue: String? = nil) {
       addOption(optionKey, valueType: .string, optionType: optionType, defaultValue: defaultValue)
     }

     func addStringEnumOption(_ optionKey: TulsiOptionKey,
                              _ optionType: TulsiOption.OptionType,
                              _ defaultValue: String,
                              _ values: [String]) {
       assert(values.contains(defaultValue), "Invalid enum for \(optionKey.rawValue): " +
           "defaultValue of \"\(defaultValue)\" is not present in enum values: \(values).")
       addOption(optionKey, valueType: .stringEnum(Set(values)),
                 optionType: optionType, defaultValue: defaultValue)
     }

     addBoolOption(.ALWAYS_SEARCH_USER_PATHS, .BuildSetting, false)
     addBoolOption(.BazelContinueBuildingAfterError, .Generic, false)
     addStringOption(.BazelBuildOptionsDebug, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.BazelBuildOptionsRelease, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.BazelBuildStartupOptionsDebug, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.BazelBuildStartupOptionsRelease, [.TargetSpecializable, .SupportsInheritKeyword])
     addBoolOption(.SuppressSwiftUpdateCheck, .Generic, true)
     addBoolOption(.IncludeBuildSources, .Generic, false)
     addBoolOption(.ImprovedImportAutocompletionFix, .Generic, true)
     addBoolOption(.GenerateRunfiles, .Generic, false)
     addBoolOption(.ProjectPrioritizesSwift, .Generic, false)
     addBoolOption(.SwiftForcesdSYMs, .Generic, false)
     addBoolOption(.TreeArtifactOutputs, .Generic, true)

     let defaultIdentifier = PlatformConfiguration.defaultConfiguration.identifier
     let platformCPUIdentifiers = PlatformConfiguration.allValidConfigurations.map { $0.identifier }
     addStringEnumOption(.ProjectGenerationPlatformConfiguration, .Generic,
                         defaultIdentifier, platformCPUIdentifiers)
     addStringEnumOption(.ProjectGenerationCompilationMode, .Generic, "dbg", ["dbg", "opt"])
     addStringOption(.ProjectGenerationBazelStartupOptions, [.SupportsInheritKeyword])

     addStringOption(.CommandlineArguments, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.EnvironmentVariables, [.TargetSpecializable, .SupportsInheritKeyword])

     // List matches the available options for the 'C++ Language Dialect' setting in XCode 10.2.1 and 11.
     // Currently compiler default is equivalent to GNU++98 (Xcode 10.2.1 and 11)
     let cppLanguageStandards = ["compiler-default", "c++98", "gnu++98", "c++11", "gnu++11", "c++14", "gnu++14", "c++17", "gnu++17"]
     addStringEnumOption(.CLANG_CXX_LANGUAGE_STANDARD, .BuildSetting, "gnu++17",  cppLanguageStandards)

     addStringOption(.PreBuildPhaseRunScript, [.TargetSpecializable])
     addStringOption(.PostBuildPhaseRunScript, [.TargetSpecializable])
     addStringOption(.BuildActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.LaunchActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.TestActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.BuildActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.LaunchActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
     addStringOption(.TestActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])

     addStringOption(.BazelPath, [.Hidden, .PerUserOnly])
     addStringOption(.WorkspaceRootPath, [.Hidden, .PerUserOnly])
   }

   private func populateOptionGroupInfoWithBundle(_ bundle: Bundle) {
     for (_, keyGroup) in TulsiOptionSet.OptionKeyGroups {
       if optionKeyGroupInfo[keyGroup] == nil {
         let key = keyGroup.rawValue
         let displayName = NSLocalizedString(key, tableName: "Options", bundle: bundle, comment: "")
         let descriptionKey = key + TulsiOptionSet.DescriptionStringKeySuffix
         let description = NSLocalizedString(descriptionKey, tableName: "Options", bundle: bundle, comment: "")
         optionKeyGroupInfo[keyGroup] = (displayName, description)
       }
     }
   }
 }

 public func ==(lhs: TulsiOptionSet, rhs: TulsiOptionSet) -> Bool {
   for (key, option) in lhs.options {
     if rhs[key] != option {
       return false
     }
   }
   return true
 }
	// Copyright 2016 The Tulsi Authors. All rights reserved.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	import Foundation


	/// Keys for all user modifiable Tulsi options.
	// Style note: Entries that map directly to Xcode Build Settings values are all caps (matching
	// Xcode's use) while entries handled in Tulsi are camel case.
	public enum TulsiOptionKey: String {
	case
	// Whether or not to search user header paths first when resolving angle bracket includes.
	ALWAYS_SEARCH_USER_PATHS,

	// What C++ language standard to use for the project.
	CLANG_CXX_LANGUAGE_STANDARD,

	// The path to the Bazel binary.
	BazelPath,
	// Whether or not to claim Swift code was created at the same version as Tulsi itself.
	// Suppresses the Xcode warning and automated update on first opening of the generated
	// project.
	SuppressSwiftUpdateCheck,
	// Whether or not containing a Swift dependency forces dSYM generation (used for debugging).
	SwiftForcesdSYMs,
	// Whether or not to use tree artifact outputs. Should only be disabled if it causes errors.
	// Known issues:
	// - Bundles with spaces in the name
	TreeArtifactOutputs,
	// The path from a config file to its associated workspace root.
	WorkspaceRootPath,

	// Commandline Arguments used by the run phase of the generated scheme.
	CommandlineArguments,

	// Environment Variables used by the run phase of the generated scheme.
	EnvironmentVariables,

	// Option to enable compilation after error.
	BazelContinueBuildingAfterError,

	// Include all .bzl files related to the build in the generated Xcodeproj.
	IncludeBuildSources,

	// Compilation mode to use during project generation.
	ProjectGenerationCompilationMode,

	// Platform configuration to use during project generation.
	ProjectGenerationPlatformConfiguration,

	// Startup options for project generation.
	ProjectGenerationBazelStartupOptions,

	// Improve auto-completion for include/import statements.
	ImprovedImportAutocompletionFix,

	// Generate .runfiles directory, as referenced by TEST_SRCDIR in bazel tests.
	GenerateRunfiles,

	// Used by Tulsi to improve Bazel-caching of build flags.
	ProjectPrioritizesSwift,

	// Custom build phase run script that runs before bazel build.
	PreBuildPhaseRunScript,

	// Custom build phase run script that runs after bazel build.
	PostBuildPhaseRunScript

	// Options for build invocations.
	case BazelBuildOptionsDebug,
	BazelBuildOptionsRelease

	// Startup options for build invocations.
	case BazelBuildStartupOptionsDebug,
	BazelBuildStartupOptionsRelease

	// Pre action scripts for build, launch, and test actions.
	case BuildActionPreActionScript,
	LaunchActionPreActionScript,
	TestActionPreActionScript

	// Post action scripts for build, launch, and test actions.
	case BuildActionPostActionScript,
	LaunchActionPostActionScript,
	TestActionPostActionScript
	}


	/// Logical groupings for TulsiOptionKeys.
	public enum TulsiOptionKeyGroup: String {
	case BazelBuildOptions,
	BazelBuildStartupOptions,
	PreActionScriptOptions,
	PostActionScriptOptions
	}


	/// Models the set of all user-modifiable options supported by Tulsi.
	public class TulsiOptionSet: Equatable {
	/// Suffix added to string keys in order to resolve an option's description.
	static let DescriptionStringKeySuffix = "_DESC"

	/// The key under which option sets are serialized.
	static let PersistenceKey = "optionSet"

	typealias PersistenceType = [String: TulsiOption.PersistenceType]

	static let OptionKeyGroups: [TulsiOptionKey: TulsiOptionKeyGroup] = [
	.ProjectGenerationBazelStartupOptions: .BazelBuildStartupOptions,
	.BazelBuildOptionsDebug: .BazelBuildOptions,
	.BazelBuildOptionsRelease: .BazelBuildOptions,
	.BazelBuildStartupOptionsDebug: .BazelBuildStartupOptions,
	.BazelBuildStartupOptionsRelease: .BazelBuildStartupOptions,
	.BuildActionPreActionScript: .PreActionScriptOptions,
	.LaunchActionPreActionScript: .PreActionScriptOptions,
	.TestActionPreActionScript: .PreActionScriptOptions,
	.BuildActionPostActionScript: .PostActionScriptOptions,
	.LaunchActionPostActionScript: .PostActionScriptOptions,
	.TestActionPostActionScript: .PostActionScriptOptions
	]

	public var allVisibleOptions = [TulsiOptionKey: TulsiOption]()
	var options = [TulsiOptionKey: TulsiOption]() {
	didSet {
	allVisibleOptions = [TulsiOptionKey: TulsiOption]()
	for (key, option) in options {
	if !option.optionType.contains(.Hidden) {
	allVisibleOptions[key] = option
	}
	}
	}
	}
	var optionKeyGroupInfo = [TulsiOptionKeyGroup: (displayName: String, description: String)]()

	public subscript(optionKey: TulsiOptionKey) -> TulsiOption {
	return options[optionKey]!
	}

	public subscript(optionKey: TulsiOptionKey, target: String) -> String? {
	return options[optionKey]?.valueForTarget(target)
	}

	static func getOptionsFromContainerDictionary(_ dict: [String: Any]) -> PersistenceType? {
	return dict[TulsiOptionSet.PersistenceKey] as? PersistenceType
	}

	public init(withInheritanceEnabled inherit: Bool = false) {
	let bundle = Bundle(for: type(of: self))
	populateOptionsWithBundle(bundle, withInheritAsDefault: inherit)
	populateOptionGroupInfoWithBundle(bundle)
	}

	public convenience init(fromDictionary dict: [String: Any]) {
	self.init()

	guard let persistedOptions = dict as? PersistenceType else {
	assertionFailure("Options dictionary is not of the expected type")
	return
	}

	for (key, option) in options {
	if let value = persistedOptions[key.rawValue] {
	option.deserialize(value)
	}
	}
	}

	/// Returns a new TulsiOptionSet by using the given parent as a base and applying this option
	/// set's options as overrides.
	public func optionSetByInheritingFrom(_ parent: TulsiOptionSet) -> TulsiOptionSet {
	var resolvedOptions = [TulsiOptionKey: TulsiOption]()
	for (key, opt) in options {
	guard let parentOption = parent.options[key] else {
	resolvedOptions[key] = opt
	continue
	}
	resolvedOptions[key] = TulsiOption(resolvingValuesFrom: opt, byInheritingFrom: parentOption)
	}

	let resolvedSet = TulsiOptionSet()
	resolvedSet.options = resolvedOptions
	return resolvedSet
	}

	func saveShareableOptionsIntoDictionary(_ dict: inout [String: Any]) {
	let serialized = saveToDictionary() {
	!$1.optionType.contains(.PerUserOnly)
	}
	dict[TulsiOptionSet.PersistenceKey] = serialized
	}

	func savePerUserOptionsIntoDictionary(_ dict: inout [String: Any]) {
	let serialized = saveToDictionary() {
	return $1.optionType.contains(.PerUserOnly)
	}
	dict[TulsiOptionSet.PersistenceKey] = serialized
	}

	func saveAllOptionsIntoDictionary(_ dict: inout [String: AnyObject]) {
	let serialized = saveToDictionary() { (_, _) in return true }
	dict[TulsiOptionSet.PersistenceKey] = serialized as AnyObject?
	}

	public func groupInfoForOptionKey(_ key: TulsiOptionKey) -> (TulsiOptionKeyGroup, displayName: String, description: String)? {
	guard let keyGroup = TulsiOptionSet.OptionKeyGroups[key] else { return nil }
	guard let (displayName, description) = optionKeyGroupInfo[keyGroup] else {
	assertionFailure("Missing group information for group key \(keyGroup)")
	return (keyGroup, "\(keyGroup)", "")
	}
	return (keyGroup, displayName, description)
	}

	/// Returns a dictionary of build settings without applying any specializations.
	func commonBuildSettings() -> [String: String] {
	// These values come from AppleToolchain.java in Bazel
	// https://github.com/bazelbuild/bazel/blob/master/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java
	var buildSettings = [
	"GCC_WARN_64_TO_32_BIT_CONVERSION": "YES",
	"CLANG_WARN_BOOL_CONVERSION": "YES",
	"CLANG_WARN_CONSTANT_CONVERSION": "YES",
	"CLANG_WARN__DUPLICATE_METHOD_MATCH": "YES",
	"CLANG_WARN_EMPTY_BODY": "YES",
	"CLANG_WARN_ENUM_CONVERSION": "YES",
	"CLANG_WARN_INT_CONVERSION": "YES",
	"CLANG_WARN_UNREACHABLE_CODE": "YES",
	"GCC_WARN_ABOUT_RETURN_TYPE": "YES",
	"GCC_WARN_UNDECLARED_SELECTOR": "YES",
	"GCC_WARN_UNINITIALIZED_AUTOS": "YES",
	"GCC_WARN_UNUSED_FUNCTION": "YES",
	"GCC_WARN_UNUSED_VARIABLE": "YES",
	]

	for (key, opt) in options.filter({ $1.optionType.contains(.BuildSetting) }) {
	buildSettings[key.rawValue] = opt.commonValue!
	}
	return buildSettings
	}

	/// Returns a dictionary of build settings specialized for the given target without inheriting any
	/// defaults.
	func buildSettingsForTarget(_ target: String) -> [String: String] {
	var buildSettings = [String: String]()
	for (key, opt) in options.filter({ $1.optionType.contains(.TargetSpecializableBuildSetting) }) {
	if let val = opt.valueForTarget(target, inherit: false) {
	buildSettings[key.rawValue] = val
	}
	}
	return buildSettings
	}

	// MARK: - Private methods.

	private func saveToDictionary(_ filter: (TulsiOptionKey, TulsiOption) -> Bool) -> PersistenceType {
	var serialized = PersistenceType()
	for (key, option) in options.filter(filter) {
	if let value = option.serialize() {
	serialized[key.rawValue] = value
	}
	}
	return serialized
	}

	private func populateOptionsWithBundle(_ bundle: Bundle, withInheritAsDefault inherit: Bool) {
	func addOption(_ optionKey: TulsiOptionKey, valueType: TulsiOption.ValueType, optionType: TulsiOption.OptionType, defaultValue: String?) {
	let key = optionKey.rawValue
	let displayName = bundle.localizedString(forKey: key, value: nil, table: "Options")
	let descriptionKey = key + TulsiOptionSet.DescriptionStringKeySuffix
	var description = bundle.localizedString(forKey: descriptionKey, value: nil, table: "Options")
	if description == descriptionKey { description = "" }

	let opt = TulsiOption(displayName: displayName,
	userDescription: description,
	valueType: valueType,
	optionType: optionType,
	defaultValue: defaultValue)
	if inherit && optionType.contains(.SupportsInheritKeyword) {
	opt.projectValue = TulsiOption.InheritKeyword
	}
	options[optionKey] = opt
	}

	func addBoolOption(_ optionKey: TulsiOptionKey, _ optionType: TulsiOption.OptionType, _ defaultValue: Bool = false) {
	let val = defaultValue ? TulsiOption.BooleanTrueValue : TulsiOption.BooleanFalseValue
	addOption(optionKey, valueType: .bool, optionType: optionType, defaultValue: val)
	}

	func addStringOption(_ optionKey: TulsiOptionKey, _ optionType: TulsiOption.OptionType, _ defaultValue: String? = nil) {
	addOption(optionKey, valueType: .string, optionType: optionType, defaultValue: defaultValue)
	}

	func addStringEnumOption(_ optionKey: TulsiOptionKey,
	_ optionType: TulsiOption.OptionType,
	_ defaultValue: String,
	_ values: [String]) {
	assert(values.contains(defaultValue), "Invalid enum for \(optionKey.rawValue): " +
	"defaultValue of \"\(defaultValue)\" is not present in enum values: \(values).")
	addOption(optionKey, valueType: .stringEnum(Set(values)),
	optionType: optionType, defaultValue: defaultValue)
	}

	addBoolOption(.ALWAYS_SEARCH_USER_PATHS, .BuildSetting, false)
	addBoolOption(.BazelContinueBuildingAfterError, .Generic, false)
	addStringOption(.BazelBuildOptionsDebug, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.BazelBuildOptionsRelease, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.BazelBuildStartupOptionsDebug, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.BazelBuildStartupOptionsRelease, [.TargetSpecializable, .SupportsInheritKeyword])
	addBoolOption(.SuppressSwiftUpdateCheck, .Generic, true)
	addBoolOption(.IncludeBuildSources, .Generic, false)
	addBoolOption(.ImprovedImportAutocompletionFix, .Generic, true)
	addBoolOption(.GenerateRunfiles, .Generic, false)
	addBoolOption(.ProjectPrioritizesSwift, .Generic, false)
	addBoolOption(.SwiftForcesdSYMs, .Generic, false)
	addBoolOption(.TreeArtifactOutputs, .Generic, true)

	let defaultIdentifier = PlatformConfiguration.defaultConfiguration.identifier
	let platformCPUIdentifiers = PlatformConfiguration.allValidConfigurations.map { $0.identifier }
	addStringEnumOption(.ProjectGenerationPlatformConfiguration, .Generic,
	defaultIdentifier, platformCPUIdentifiers)
	addStringEnumOption(.ProjectGenerationCompilationMode, .Generic, "dbg", ["dbg", "opt"])
	addStringOption(.ProjectGenerationBazelStartupOptions, [.SupportsInheritKeyword])

	addStringOption(.CommandlineArguments, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.EnvironmentVariables, [.TargetSpecializable, .SupportsInheritKeyword])

	// List matches the available options for the 'C++ Language Dialect' setting in XCode 10.2.1 and 11.
	// Currently compiler default is equivalent to GNU++98 (Xcode 10.2.1 and 11)
	let cppLanguageStandards = ["compiler-default", "c++98", "gnu++98", "c++11", "gnu++11", "c++14", "gnu++14", "c++17", "gnu++17"]
	addStringEnumOption(.CLANG_CXX_LANGUAGE_STANDARD, .BuildSetting, "gnu++17", cppLanguageStandards)

	addStringOption(.PreBuildPhaseRunScript, [.TargetSpecializable])
	addStringOption(.PostBuildPhaseRunScript, [.TargetSpecializable])
	addStringOption(.BuildActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.LaunchActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.TestActionPreActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.BuildActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.LaunchActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])
	addStringOption(.TestActionPostActionScript, [.TargetSpecializable, .SupportsInheritKeyword])

	addStringOption(.BazelPath, [.Hidden, .PerUserOnly])
	addStringOption(.WorkspaceRootPath, [.Hidden, .PerUserOnly])
	}

	private func populateOptionGroupInfoWithBundle(_ bundle: Bundle) {
	for (_, keyGroup) in TulsiOptionSet.OptionKeyGroups {
	if optionKeyGroupInfo[keyGroup] == nil {
	let key = keyGroup.rawValue
	let displayName = NSLocalizedString(key, tableName: "Options", bundle: bundle, comment: "")
	let descriptionKey = key + TulsiOptionSet.DescriptionStringKeySuffix
	let description = NSLocalizedString(descriptionKey, tableName: "Options", bundle: bundle, comment: "")
	optionKeyGroupInfo[keyGroup] = (displayName, description)
	}
	}
	}
	}

	public func ==(lhs: TulsiOptionSet, rhs: TulsiOptionSet) -> Bool {
	for (key, option) in lhs.options {
	if rhs[key] != option {
	return false
	}
	}
	return true
	}