add testing

3 files changed, 42 insertions, 0 deletions

diff --git a/README.md b/README.md
index b702cecef..2c2914b89 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,14 @@ Limitations:
  * WebAssembly lacks global variables, so `asm2wasm` maps them onto addresses in memory. This requires that you have some reserved space for those variables. You can do that with `emcc -s GLOBAL_BASE=1000`. We still need to write the code to copy the globals there.
  * Emscripten emits asm.js and JavaScript, that work together using web APIs to do things like print, render, etc. Not sure if there is a way to test that full output yet.
 
+## Testing
+
+```
+./check.py
+```
+
+(or `python check.py`) will run `asm2wasm` on the testcases in `test/`, and verify their outputs.
+
 ## License & Contributing
 
 Same as Emscripten: MIT license. This code is sync'ed with Emscripten's repo.
diff --git a/check.py b/check.py
new file mode 100755
index 000000000..62fa98e9f
--- /dev/null
+++ b/check.py
@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+
+import os, subprocess, difflib
+
+print 'checking testcases...\n'
+
+for asm in os.listdir('test'):
+  if asm.endswith('.asm.js'):
+    print '  ', asm, ' ',
+    wasm = asm.replace('.asm.js', '.wasm')
+    actual, err = subprocess.Popen([os.path.join('bin', 'asm2wasm'), os.path.join('test', asm)], stdout=subprocess.PIPE, stderr=subprocess.PIPE).communicate()
+    assert err == '', 'bad err:' + err
+    expected = open(os.path.join('test', wasm)).read()
+    if actual != expected:
+      raise Exception("Expected to have '%s' == '%s', diff:\n\n%s" % (
+        expected, actual,
+        limit_size(''.join([a.rstrip()+'\n' for a in difflib.unified_diff(x.split('\n'), y.split('\n'), fromfile='expected', tofile='actual')]))
+      ))
+    print 'OK'
+
+print '\nsuccess!'
diff --git a/test/hello_world.wasm b/test/hello_world.wasm
new file mode 100644
index 000000000..66dd61c42
--- /dev/null
+++ b/test/hello_world.wasm
@@ -0,0 +1,13 @@
+(module
+  (export $add "add" $add)
+  (func $add (param $x i32) (param $y i32) (result i32)
+    (block $topmost
+      (break $topmost
+        (i32.add
+          (get_local $x)
+          (get_local $y)
+        )
+      )
+    )
+  )
+)