WAT: Do not try repairing invalid UTF-8 strings

Author: kateinoigakukun

Sources/WAT/Parser.swift

@@ -154,7 +154,14 @@ internal struct Parser {
         return text
     }
     mutating func expectString() throws -> String {
-        String(decoding: try expectStringBytes(), as: UTF8.self)
+        // TODO: Use SE-0405 once we can upgrade minimum-supported Swift version to 6.0
+        let bytes = try expectStringBytes()
+        return try bytes.withUnsafeBufferPointer {
+            guard let value = String._tryFromUTF8($0) else {
+                throw WatParserError("invalid UTF-8 string", location: lexer.location())
+            }
+            return value
+        }
     }
 
     mutating func expectStringList() throws -> [UInt8] {

Tests/WATTests/EncoderTests.swift

@@ -106,9 +106,7 @@ class EncoderTests: XCTestCase {
             }
 
             var stats = CompatibilityTestStats()
-            let excluded: [String] = [
-                "utf8-invalid-encoding.wast"
-            ]
+            let excluded: [String] = []
             for wastFile in Spectest.wastFiles(include: [], exclude: excluded) {
                 try TestSupport.withTemporaryDirectory { tempDir, shouldRetain in
                     let jsonFileName = wastFile.deletingPathExtension().lastPathComponent + ".json"