correctly validate characters in semantic version identifiers

Semantic Versioning 2.0.0 allows only _ASCII_ alpha-numeric characters and "-" in identifiers.

Author: WowbaggersLiquidLunch

Sources/PackageDescription/Version+StringLiteralConvertible.swift

@@ -72,7 +72,9 @@ extension Version: LosslessStringConvertible {
         if let prereleaseDelimiterIndex = prereleaseDelimiterIndex {
             let prereleaseStartIndex = versionString.index(after: prereleaseDelimiterIndex)
             let prereleaseIdentifiers = versionString[prereleaseStartIndex..<(metadataDelimiterIndex ?? versionString.endIndex)].split(separator: ".", omittingEmptySubsequences: false)
-            guard prereleaseIdentifiers.allSatisfy({ $0.allSatisfy({ $0.isLetter || $0.isNumber || $0 == "-" })}) else { return nil }
+            guard prereleaseIdentifiers.allSatisfy( {
+                $0.allSatisfy( { $0.isASCII && ($0.isLetter || $0.isNumber || $0 == "-") } )
+            } ) else { return nil }
             self.prereleaseIdentifiers = prereleaseIdentifiers.map { String($0) }
         } else {
             self.prereleaseIdentifiers = []
@@ -81,7 +83,9 @@ extension Version: LosslessStringConvertible {
         if let metadataDelimiterIndex = metadataDelimiterIndex {
             let metadataStartIndex = versionString.index(after: metadataDelimiterIndex)
             let buildMetadataIdentifiers = versionString[metadataStartIndex...].split(separator: ".", omittingEmptySubsequences: false)
-            guard buildMetadataIdentifiers.allSatisfy({ $0.allSatisfy({ $0.isLetter || $0.isNumber || $0 == "-" })}) else { return nil }
+            guard buildMetadataIdentifiers.allSatisfy( {
+                $0.allSatisfy( { $0.isASCII && ($0.isLetter || $0.isNumber || $0 == "-") } )
+            } ) else { return nil }
             self.buildMetadataIdentifiers = buildMetadataIdentifiers.map { String($0) }
         } else {
             self.buildMetadataIdentifiers = []

Sources/PackageDescription/Version.swift

@@ -68,6 +68,18 @@ public struct Version {
         buildMetadataIdentifiers: [String] = []
     ) {
         precondition(major >= 0 && minor >= 0 && patch >= 0, "Negative versioning is invalid.")
+        precondition(
+            prereleaseIdentifiers.allSatisfy {
+                $0.allSatisfy { $0.isASCII && ($0.isLetter || $0.isNumber || $0 == "-") }
+            },
+            #"Pre-release identifiers can contain only ASCII alpha-numeric characters and "-"."#
+        )
+        precondition(
+            buildMetadataIdentifiers.allSatisfy {
+                $0.allSatisfy { $0.isASCII && ($0.isLetter || $0.isNumber || $0 == "-") }
+            },
+            #"Build metadata identifiers can contain only ASCII alpha-numeric characters and "-"."#
+        )
         self.major = major
         self.minor = minor
         self.patch = patch