Support exploring ".wat" files

Convert parseWasm() to be a global function instead of an an instance
method of the Run command. This wraps WasmKit.parseWasm() and supports
both ".wat" and ".wasm" files.

Author: pcbeard

Sources/CLI/Commands/Parse.swift

@@ -0,0 +1,20 @@
+import WAT
+import WasmKit
+import SystemPackage
+
+/// Parses a `.wasm` or `.wat` module.
+func parseWasm(filePath: FilePath) throws -> Module {
+    if filePath.extension == "wat", #available(macOS 11.0, iOS 14.0, macCatalyst 14.0, tvOS 14.0, visionOS 1.0, watchOS 7.0, *) {
+        let fileHandle = try FileDescriptor.open(filePath, .readOnly)
+        defer { try? fileHandle.close() }
+
+        let size = try fileHandle.seek(offset: 0, from: .end)
+
+        let wat = try String(unsafeUninitializedCapacity: Int(size)) {
+            try fileHandle.read(fromAbsoluteOffset: 0, into: .init($0))
+        }
+        return try WasmKit.parseWasm(bytes: wat2wasm(wat))
+    } else {
+        return try WasmKit.parseWasm(filePath: filePath)
+    }
+}

Sources/CLI/Commands/Run.swift

@@ -1,6 +1,5 @@
 import ArgumentParser
 import SystemPackage
-import WAT
 import WasmKit
 import WasmKitWASI
 
@@ -120,12 +119,12 @@ struct Run: ParsableCommand {
         let module: Module
         if verbose, #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) {
             let (parsedModule, parseTime) = try measure {
-                try self.parseWasm(filePath: FilePath(path))
+                try parseWasm(filePath: FilePath(path))
             }
             log("Finished parsing module: \(parseTime)", verbose: true)
             module = parsedModule
         } else {
-            module = try self.parseWasm(filePath: FilePath(path))
+            module = try parseWasm(filePath: FilePath(path))
         }
 
         let (interceptor, finalize) = try deriveInterceptor()
@@ -149,23 +148,6 @@ struct Run: ParsableCommand {
         }
     }
 
-    /// Parses a `.wasm` or `.wat` module.
-    func parseWasm(filePath: FilePath) throws -> Module {
-        if filePath.extension == "wat", #available(macOS 11.0, iOS 14.0, macCatalyst 14.0, tvOS 14.0, visionOS 1.0, watchOS 7.0, *) {
-            let fileHandle = try FileDescriptor.open(filePath, .readOnly)
-            defer { try? fileHandle.close() }
-
-            let size = try fileHandle.seek(offset: 0, from: .end)
-
-            let wat = try String(unsafeUninitializedCapacity: Int(size)) {
-                try fileHandle.read(fromAbsoluteOffset: 0, into: .init($0))
-            }
-            return try WasmKit.parseWasm(bytes: wat2wasm(wat))
-        } else {
-            return try WasmKit.parseWasm(filePath: filePath)
-        }
-    }
-
     /// Derives the runtime interceptor based on the command line arguments
     func deriveInterceptor() throws -> (interceptor: EngineInterceptor?, finalize: () -> Void) {
         var interceptors: [EngineInterceptor] = []