stmt/for: hoist multiple initial conditions from 3-clause for loops

fixtures/0002-loops.php

@@ -19,3 +19,7 @@ for($i = 0; $i < 3; ++$i) {
 
 // Loop with no separate body statement
 while (true) echo "hello";
+
+// Loop with multiple initialiser conditions
+for ($i = 0, $e = 3; $i < $e; ++$i) {	
+}

node.go

@@ -233,16 +233,32 @@ func convert(n_ node.Node) (string, error) {
 		return "return nil, " + child + "\n", nil
 
 	case *stmt.For:
-		if len(n.Init) != 1 {
+
+		var preinit, finit string
+		var err error = nil
+
+		if len(n.Init) == 0 {
+			// No initialiser in loop
+
+		} else if len(n.Init) == 1 {
+			finit, err = convert(n.Init[0])
+			if err != nil {
+				return "", parseErr{n, err}
+			}
+
+		} else {
 			// We can handle the case of multiple init statements by hoisting them
 			// above the loop. There is no negative impact on PHP scoping rules, but
 			// it may cause an extra local variable after the loop that may result
 			// in type mismatch (can be fixed by using an extra scope).
-			return "", parseErr{n, fmt.Errorf("for loop can only have 1 init clause, found %d", len(n.Init))}
-		}
-		finit, err := convert(n.Init[0])
-		if err != nil {
-			return "", parseErr{n, err}
+			for _, initStmt := range n.Init {
+				singleInitStmt, err := convert(initStmt)
+				if err != nil {
+					return "", parseErr{initStmt, err}
+				}
+
+				preinit += singleInitStmt + "\n"
+			}
 		}
 
 		if len(n.Cond) != 1 {
@@ -275,7 +291,7 @@ func convert(n_ node.Node) (string, error) {
 			return "", parseErr{n, err}
 		}
 
-		return "for " + finit + "; " + fcond + "; " + floop + " " + body + "\n", nil
+		return preinit + "for " + finit + "; " + fcond + "; " + floop + " " + body + "\n", nil
 
 	case *stmt.Foreach:
 		iterand, err := convert(n.Expr)