[Xcodeproj] Add a Plist enum

Also, moves Build settings to use this new type respecting proper
quoting rules.

- <rdar://problem/28039632> SR-1754: Spaces should be escaped in
  HEADER_SEARCH_PATHS

Author: aciidgh

Sources/Xcodeproj/Module+PBXProj.swift

@@ -155,7 +155,7 @@ extension Module  {
         }
     }
 
-    var headerSearchPaths: (key: String, value: String)? {
+    var headerSearchPaths: (key: String, value: Any)? {
         let headerPathKey = "HEADER_SEARCH_PATHS"
         var headerPaths = dependencies.flatMap { module -> AbsolutePath? in
             switch module {
@@ -174,36 +174,48 @@ extension Module  {
         }
 
         guard !headerPaths.isEmpty else { return nil }
-
-        if headerPaths.count == 1, let first = headerPaths.first {
-            return (headerPathKey, first.asString)
-        }
-
-        let headerPathValue = headerPaths.map{ $0.asString }.joined(separator: " ")
 
-        return (headerPathKey, headerPathValue)
+        return (headerPathKey, headerPaths.map { $0.asString } )
     }
 
     func getDebugBuildSettings(_ options: XcodeprojOptions, xcodeProjectPath: AbsolutePath) throws -> String {
         var buildSettings = try getCommonBuildSettings(options, xcodeProjectPath: xcodeProjectPath)
         if let headerSearchPaths = headerSearchPaths {
             buildSettings[headerSearchPaths.key] = headerSearchPaths.value
         }
-        // FIXME: Need to honor actual quoting rules here.
-        return buildSettings.map{ "\($0) = '\($1)';" }.joined(separator: " ")
+        return toPlist(buildSettings).serialize()
     }
 
     func getReleaseBuildSettings(_ options: XcodeprojOptions, xcodeProjectPath: AbsolutePath) throws -> String {
         var buildSettings = try getCommonBuildSettings(options, xcodeProjectPath: xcodeProjectPath)
         if let headerSearchPaths = headerSearchPaths {
             buildSettings[headerSearchPaths.key] = headerSearchPaths.value
         }
-        // FIXME: Need to honor actual quoting rules here.
-        return buildSettings.map{ "\($0) = '\($1)';" }.joined(separator: " ")
+        return toPlist(buildSettings).serialize()
+    }
+
+    /// Converts build settings dictionary to a Plist object.
+    ///
+    /// Adds string values in dictionaries as is and array values are quoted and then converted
+    /// to a string joined by whitespace.
+    private func toPlist(_ buildSettings: [String: Any]) -> Plist {
+        var buildSettingsPlist = [String: Plist]()
+        for (k, v) in buildSettings {
+            switch v {
+            case let value as String:
+                buildSettingsPlist[k] = .string(value)
+            case let value as [String]:
+                let escaped = value.map { "\"" + Plist.escape(string: $0) + "\"" }.joined(separator: " ")
+                buildSettingsPlist[k] = .string(escaped)
+            default:
+                fatalError("build setting dictionary should only contain String or [String]")
+            }
+        }
+        return .dictionary(buildSettingsPlist)
     }
 
-    private func getCommonBuildSettings(_ options: XcodeprojOptions, xcodeProjectPath: AbsolutePath) throws -> [String: String] {
-        var buildSettings = [String: String]()
+    private func getCommonBuildSettings(_ options: XcodeprojOptions, xcodeProjectPath: AbsolutePath) throws -> [String: Any] {
+        var buildSettings = [String: Any]()
         let plistPath = xcodeProjectPath.appending(component: infoPlistFileName)
 
         if isTest {
@@ -220,7 +232,7 @@ extension Module  {
             //
             // This means the built binaries are not suitable for distribution,
             // among other things.
-            buildSettings["LD_RUNPATH_SEARCH_PATHS"] = "$(TOOLCHAIN_DIR)/usr/lib/swift/macosx"
+            buildSettings["LD_RUNPATH_SEARCH_PATHS"] = ["$(TOOLCHAIN_DIR)/usr/lib/swift/macosx"]
             if isLibrary {
                 buildSettings["ENABLE_TESTABILITY"] = "YES"
 
@@ -259,13 +271,13 @@ extension Module  {
                 // example would be `@executable_path/../lib` but there are
                 // other problems to solve first, e.g. how to deal with the
                 // Swift standard library paths).
-                buildSettings["LD_RUNPATH_SEARCH_PATHS"] = buildSettings["LD_RUNPATH_SEARCH_PATHS"]! + " @executable_path"
+                buildSettings["LD_RUNPATH_SEARCH_PATHS"] = buildSettings["LD_RUNPATH_SEARCH_PATHS"] as! [String] + ["@executable_path"]
             }
         }
 
         if let pkgArgs = try? self.pkgConfigArgs() {
-            buildSettings["OTHER_LDFLAGS"] = (["$(inherited)"] + pkgArgs.libs).joined(separator: " ")
-            buildSettings["OTHER_SWIFT_FLAGS"] = (["$(inherited)"] + pkgArgs.cFlags).joined(separator: " ")
+            buildSettings["OTHER_LDFLAGS"] = ["$(inherited)"] + pkgArgs.libs
+            buildSettings["OTHER_SWIFT_FLAGS"] = ["$(inherited)"] + pkgArgs.cFlags
         }
 
         // Add framework search path to build settings.

Sources/Xcodeproj/Plist.swift

@@ -0,0 +1,67 @@
+/*
+ This source file is part of the Swift.org open source project
+
+ Copyright 2015 - 2016 Apple Inc. and the Swift project authors
+ Licensed under Apache License v2.0 with Runtime Library Exception
+
+ See http://swift.org/LICENSE.txt for license information
+ See http://swift.org/CONTRIBUTORS.txt for Swift project authors
+*/
+
+/// A enum representing data types for legacy Plist type.
+/// see: https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/PropertyLists/OldStylePlists/OldStylePLists.html
+enum Plist {
+    case string(String)
+    case array([Plist])
+    case dictionary([String: Plist])
+}
+
+extension Plist: ExpressibleByStringLiteral {
+    public typealias UnicodeScalarLiteralType = StringLiteralType
+    public typealias ExtendedGraphemeClusterLiteralType = StringLiteralType
+
+    public init(unicodeScalarLiteral value: UnicodeScalarLiteralType) {
+        self = .string(value)
+    }
+    public init(extendedGraphemeClusterLiteral value: ExtendedGraphemeClusterLiteralType) {
+        self = .string(value)
+    }
+    public init(stringLiteral value: StringLiteralType) {
+        self = .string(value)
+    }
+}
+
+extension Plist {
+    /// Serializes the Plist enum to string.
+    func serialize() -> String {
+        switch self {
+        case .string(let str):
+            return "\"" + Plist.escape(string: str) + "\""
+        case .array(let items):
+            return "(" + items.map { $0.serialize() }.joined(separator: ", ") + ")"
+        case .dictionary(let items):
+            return "{" + items.map { " \($0) = \($1.serialize()) " }.joined(separator: "; ") + "; };"
+        }
+    }
+
+    /// Escapes the string for plist.
+    /// Finds the instances of quote (") and backward slash (\) and prepends
+    /// the escape character backward slash (\).
+    static func escape(string: String) -> String {
+        func needsEscape(_ char: UInt8) -> Bool {
+            return char == UInt8(ascii: "\\") || char == UInt8(ascii: "\"")
+        }
+
+        guard let pos = string.utf8.index(where: needsEscape) else {
+            return string
+        }
+        var newString = String(string.utf8[string.utf8.startIndex..<pos])!
+        for char in string.utf8[pos..<string.utf8.endIndex] {
+            if needsEscape(char) {
+                newString += "\\"
+            }
+            newString += String(UnicodeScalar(char))
+        }
+        return newString
+    }
+}

Sources/Xcodeproj/pbxproj().swift

@@ -234,12 +234,12 @@ public func pbxproj(srcroot: AbsolutePath, projectRoot: AbsolutePath, xcodeprojP
         print("        };")
         print("        \(module.debugConfigurationReference) = {")
         print("            isa = XCBuildConfiguration;")
-        print("            buildSettings = { \(try module.getDebugBuildSettings(options, xcodeProjectPath: xcodeprojPath)) };")
+        print("            buildSettings = \(try module.getDebugBuildSettings(options, xcodeProjectPath: xcodeprojPath))")
         print("            name = Debug;")
         print("        };")
         print("        \(module.releaseConfigurationReference) = {")
         print("            isa = XCBuildConfiguration;")
-        print("            buildSettings = { \(try module.getReleaseBuildSettings(options, xcodeProjectPath: xcodeprojPath)) };")
+        print("            buildSettings = \(try module.getReleaseBuildSettings(options, xcodeProjectPath: xcodeprojPath))")
         print("            name = Release;")
         print("        };")
 

Tests/XcodeprojTests/PlistTests.swift

@@ -0,0 +1,20 @@
+/*
+ This source file is part of the Swift.org open source project
+
+ Copyright 2015 - 2016 Apple Inc. and the Swift project authors
+ Licensed under Apache License v2.0 with Runtime Library Exception
+
+ See http://swift.org/LICENSE.txt for license information
+ See http://swift.org/CONTRIBUTORS.txt for Swift project authors
+*/
+
+import XCTest
+@testable import Xcodeproj
+
+class PlistTests: XCTestCase {
+    func testBasics() {
+        XCTAssertEqual("\"hello \\\" world\"", Plist.string("hello \" world").serialize())
+        XCTAssertEqual("(\"hello world\", \"cool\")", Plist.array([.string("hello world"), .string("cool")]).serialize())
+        XCTAssertEqual("{ user = \"cool\" ;  polo = (\"hello \\\" world\", \"cool\") ; };", Plist.dictionary(["user": .string("cool"), "polo": Plist.array([.string("hello \" world"), .string("cool")])]).serialize())
+    }
+}