Allow running spec tests on wasm port

test/run-spec-test.py

@@ -170,7 +170,23 @@ from queue import Queue, Empty
 
 class Wasm3():
     def __init__(self, executable):
-        self.exe = executable
+        if executable.endswith(".wasm"):
+            (engine, executable) = executable.split(maxsplit=1)
+
+            if engine == "wasmer":
+                self.exe = [engine, "run", "--dir=.", executable, "--"]
+            #elif engine == "wasmer-js":
+            #    self.exe = [engine, "run", executable]
+            elif engine == "wasirun":
+                self.exe = [engine, executable]
+            elif engine == "wasmtime":
+                self.exe = [engine, "--dir=.", "--optimize", executable, "--"]
+            elif engine == "iwasm":
+                self.exe = [engine, "--dir=.", executable]
+            else:
+                fatal(f"Don't know how to run engine {engine}")
+        else:
+            self.exe = [executable]
         self.p = None
         self.timeout = 3.0
 
@@ -180,7 +196,7 @@ class Wasm3():
 
         self.loaded = fn
         self.p = Popen(
-            [self.exe, "--repl", fn],
+            self.exe + ["--repl", fn],
             shell = False,
             bufsize=0, stdin=PIPE, stdout=PIPE, stderr=STDOUT
         )