From c8fe27d6c49e46351df572b0902926a19dc9eb07 Mon Sep 17 00:00:00 2001
From: Bob Nystrom <robert@stuffwithstuff.com>
Date: Sun, 29 Dec 2013 10:46:21 -0800
Subject: [PATCH] Allow empty blocks.

---
 src/wren_compiler.c            | 3 +++
 src/wren_vm.c                  | 4 ++--
 test/empty_block.wren          | 7 +++++++
 test/function/empty_block.wren | 2 ++
 test/method/empty_block.wren   | 5 +++++
 5 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 test/empty_block.wren
 create mode 100644 test/function/empty_block.wren
 create mode 100644 test/method/empty_block.wren

diff --git a/src/wren_compiler.c b/src/wren_compiler.c
index 6085fd02..47bbeb6f 100644
--- a/src/wren_compiler.c
+++ b/src/wren_compiler.c
@@ -1192,6 +1192,9 @@ static void patchJump(Compiler* compiler, int offset)
 // Parses a block body, after the initial "{" has been consumed.
 static void finishBlock(Compiler* compiler)
 {
+  // Empty blocks do nothing.
+  if (match(compiler, TOKEN_RIGHT_BRACE)) return;
+
   for (;;)
   {
     definition(compiler);
diff --git a/src/wren_vm.c b/src/wren_vm.c
index a2e4d128..e101c19e 100644
--- a/src/wren_vm.c
+++ b/src/wren_vm.c
@@ -1288,9 +1288,9 @@ void wrenDefineMethod(WrenVM* vm, const char* className,
 
 double wrenGetArgumentDouble(WrenVM* vm, int index)
 {
-  ASSERT(vm->nativeCallSlot != NULL, "Must be in foreign call.");
+  ASSERT(vm->foreignCallSlot != NULL, "Must be in foreign call.");
   ASSERT(index >= 0, "index cannot be negative.");
-  ASSERT(index < vm->nativeCallNumArgs, "Not that many arguments.");
+  ASSERT(index < vm->foreignCallNumArgs, "Not that many arguments.");
 
   // + 1 to shift past the receiver.
   // TODO: Check actual value type first.
diff --git a/test/empty_block.wren b/test/empty_block.wren
new file mode 100644
index 00000000..71591ff7
--- /dev/null
+++ b/test/empty_block.wren
@@ -0,0 +1,7 @@
+{} // By itself.
+
+// In a statement.
+if (true) {}
+if (false) {} else {}
+
+IO.write("ok") // expect: ok
\ No newline at end of file
diff --git a/test/function/empty_block.wren b/test/function/empty_block.wren
new file mode 100644
index 00000000..632e7ba2
--- /dev/null
+++ b/test/function/empty_block.wren
@@ -0,0 +1,2 @@
+var f = fn {}
+IO.write(f.call) // expect: null
diff --git a/test/method/empty_block.wren b/test/method/empty_block.wren
new file mode 100644
index 00000000..da578d24
--- /dev/null
+++ b/test/method/empty_block.wren
@@ -0,0 +1,5 @@
+class Foo {
+  bar {}
+}
+
+IO.write((new Foo).bar) // expect: null