tools/tinytest-codegen.py: Generate code for upytesthelper.

The way tinytest was used in qemu-arm test target is that it didn't test
much. MicroPython tests are based on matching the test output against
reference output, but qemu-arm's implementation didn't do that, it
effectively tested just that there was no exception during test
execution. "upytesthelper" wrapper was introduce to fix it, and so
test generator is now switched to generate test code for it.

Also, fix PEP8 and other codestyle issues.

tools/tinytest-codegen.py

@@ -1,32 +1,38 @@
-#! /usr/bin/env python3
+#!/usr/bin/env python3
 
 import os, sys
 from glob import glob
 from re import sub
 
 def escape(s):
-  lookup = {
-    '\0': '\\0',
-    '\t': '\\t',
-    '\n': '\\n\"\n\"',
-    '\r': '\\r',
-    '\\': '\\\\',
-    '\"': '\\\"',
-  }
-  return "\"\"\n\"{}\"".format(''.join([lookup[x] if x in lookup else x for x in s]))
+    s = s.decode()
+    lookup = {
+        '\0': '\\0',
+        '\t': '\\t',
+        '\n': '\\n\"\n\"',
+        '\r': '\\r',
+        '\\': '\\\\',
+        '\"': '\\\"',
+    }
+    return "\"\"\n\"{}\"".format(''.join([lookup[x] if x in lookup else x for x in s]))
 
 def chew_filename(t):
-  return { 'func': "test_{}_fn".format(sub(r'/|\.|-', '_', t)), 'desc': t.split('/')[1] }
+    return { 'func': "test_{}_fn".format(sub(r'/|\.|-', '_', t)), 'desc': t.split('/')[1] }
 
-def script_to_map(t):
-  r = { 'name': chew_filename(t)['func'] }
-  with open(t) as f: r['script'] = escape(''.join(f.readlines()))
-  return r
+def script_to_map(test_file):
+    r = {"name": chew_filename(test_file)["func"]}
+    with open(test_file, "rb") as f:
+        r["script"] = escape(f.read())
+    with open(test_file + ".exp", "rb") as f:
+        r["output"] = escape(f.read())
+    return r
 
 test_function = (
     "void {name}(void* data) {{\n"
-    "  const char * pystr = {script};\n"
-    "  do_str(pystr);\n"
+    "  static const char pystr[] = {script};\n"
+    "  static const char exp[] = {output};\n"
+    "  upytest_set_expected_output(exp, sizeof(exp) - 1);\n"
+    "  upytest_execute_test(pystr);\n"
     "}}"
 )
 
@@ -57,10 +63,10 @@ exclude_tests = (
 output = []
 
 for group in test_dirs:
-  tests = [test for test in glob('{}/*.py'.format(group)) if test not in exclude_tests]
-  output.extend([test_function.format(**script_to_map(test)) for test in tests])
-  testcase_members = [testcase_member.format(**chew_filename(test)) for test in tests]
-  output.append(testcase_struct.format(name=group, body='\n'.join(testcase_members)))
+    tests = [test for test in glob('{}/*.py'.format(group)) if test not in exclude_tests]
+    output.extend([test_function.format(**script_to_map(test)) for test in tests])
+    testcase_members = [testcase_member.format(**chew_filename(test)) for test in tests]
+    output.append(testcase_struct.format(name=group, body='\n'.join(testcase_members)))
 
 testgroup_members = [testgroup_member.format(name=group) for group in test_dirs]