Implement YAML schemas for properly reading and writing scalars

Package.swift

@@ -16,13 +16,15 @@ import PackageDescription
  let pcDeps: [Target.Dependency] = [
   "BigInt",
   .product(name: "Collections", package: "swift-collections"),
-  .byName(name: "Float16", condition: .when(platforms: [.macOS, .macCatalyst, .linux]))
+  .byName(name: "Float16", condition: .when(platforms: [.macOS, .macCatalyst, .linux])),
+  .product(name: "Regex", package: "regex"),
  ]
  #else
  let pcDeps: [Target.Dependency] = [
   "BigInt",
   .product(name: "Collections", package: "swift-collections"),
   "Float16",
+  .product(name: "Regex", package: "regex"),
  ]
  #endif
 
@@ -43,7 +45,8 @@ let package = Package(
   dependencies: [
     .package(url: "https://github.com/attaswift/BigInt.git", .upToNextMinor(from: "5.3.0")),
     .package(url: "https://github.com/SusanDoggie/Float16.git", .upToNextMinor(from: "1.1.1")),
-    .package(url: "https://github.com/apple/swift-collections.git", .upToNextMinor(from: "1.0.4"))
+    .package(url: "https://github.com/apple/swift-collections.git", .upToNextMinor(from: "1.0.4")),
+    .package(url: "https://github.com/sharplet/Regex.git", .upToNextMinor(from: "2.1.1"))
   ],
   targets: [
     .target(
@@ -100,7 +103,8 @@ let package = Package(
         "PotentCodables",
         "BigInt",
         "Cfyaml",
-        .product(name: "Collections", package: "swift-collections")
+        .product(name: "Collections", package: "swift-collections"),
+        .product(name: "Regex", package: "regex")
       ]
     ),
     .testTarget(

Sources/PotentCodables/Regexes.swift

@@ -0,0 +1,34 @@
+//
+//  Pattern.swift
+//  PotentCodables
+//
+//  Copyright © 2019 Outfox, inc.
+//
+//
+//  Distributed under the MIT License, See LICENSE for details.
+//
+
+import Foundation
+import Regex
+
+
+extension Regex: ExpressibleByStringLiteral {
+
+  public init(stringLiteral value: StaticString) {
+    self.init(value)
+  }
+
+}
+
+extension Regex {
+
+  public static func anyOf(_ regexes: Regex...) -> Regex {
+    do {
+      return try Regex(string: regexes.map { "(\($0.description))" }.joined(separator: "|"))
+    }
+    catch {
+      preconditionFailure("unexpected error creating regex from joined set: \(error)")
+    }
+  }
+
+}

Sources/PotentYAML/Cfyaml.swift → Sources/PotentYAML/Libfyaml.swift

@@ -1,5 +1,5 @@
 //
-//  Cfyaml.swift
+//  Libfyaml.swift
 //  PotentCodables
 //
 //  Copyright © 2021 Outfox, inc.
@@ -11,7 +11,7 @@
 import Cfyaml
 
 
-enum Libfyaml {
+internal enum Libfyaml {
 
   internal static func createParser() -> OpaquePointer? {
 
@@ -91,6 +91,28 @@ enum Libfyaml {
     return diag
   }
 
+  internal static func hasError(in diag: OpaquePointer?) -> Bool {
+
+    guard let diag else {
+      return true
+    }
+
+    return fy_diag_got_error(diag)
+  }
+
+  internal static func error(from diag: OpaquePointer?) -> (message: String, line: Int, column: Int)? {
+
+    guard let diag else {
+      return nil
+    }
+
+    var prev: UnsafeMutableRawPointer?
+    guard let error = fy_diag_errors_iterate(diag, &prev) else {
+      return nil
+    }
+
+    return (String(cString: error.pointee.msg), Int(error.pointee.line), Int(error.pointee.column))
+  }
 
 }
 

Sources/PotentYAML/YAML.swift

@@ -75,8 +75,8 @@ public enum YAML {
       self.isNegative = isNegative
     }
 
-    public init(_ value: String) {
-      self.init(value, isInteger: value.allSatisfy { $0.isNumber || $0 == "-" }, isNegative: value.hasPrefix("-"))
+    public init(_ value: String, schema: YAMLSchema = .core) {
+      self.init(value, isInteger: schema.isInt(value), isNegative: value.hasPrefix("-"))
     }
 
     public init<T: FloatingPoint>(_ value: T) {
@@ -193,6 +193,10 @@ public enum YAML {
     case doubleQuoted = 2
     case literal = 3
     case folded = 4
+
+    public var isQuoted: Bool {
+      self == .singleQuoted || self == .doubleQuoted
+    }
   }
 
   public enum CollectionStyle: Int32 {