tests: Add some tests to improve coverage.

Used gcov to find some parts of vm.c, runtime.c, obj.c that were not
covered by any tests.  Still need to use gcov more thoroughly.

tests/basics/builtin_hash.py

 # test builtin hash function
 
+print(hash(False))
+print(hash(True))
+print({():1}) # hash tuple
+print({1 << 66:1}) # hash big int
+print(hash in {hash:1}) # hash function
+
+try:
+    hash([])
+except TypeError:
+    print("TypeError")
+
 class A:
     def __hash__(self):
         return 123

tests/basics/del_global.py

+# del global
+
+def do_del():
+    global x
+    del x
+
+x = 1
+print(x)
+do_del()
+try:
+    print(x)
+except NameError:
+    print("NameError")
+try:
+    do_del()
+except: # NameError:
+    # FIXME uPy returns KeyError for this
+    print("NameError")

tests/basics/del_name.py

-# del global
+# del name
 
 x = 1
 print(x)

tests/basics/fun_largestate.py

@@ -129,5 +129,9 @@ def f():
     x125 = 1
     x126 = 1
 
+f()
+
 def g():
     x = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,]
+
+g()

tests/basics/int1.py

+print(int(False))
+print(int(True))
+
 print(int(0))
 print(int(1))
 print(int(+1))

tests/basics/int_small.py

@@ -49,6 +49,15 @@ print(a)
 # This would overflow
 #a -= 1
 
+# negative shifts are not allowed
+try:
+    a << -1
+except ValueError:
+    print("ValueError")
+try:
+    a >> -1
+except ValueError:
+    print("ValueError")
 
 # Shifts to big amounts are undefined behavior in C and is CPU-specific
 

tests/basics/unary_op.py

+x = 1
+print(+x)
+print(-x)
+print(~x)
+
 print(not None)
 print(not False)
 print(not True)

tests/float/int_power.py

+# negative power should produce float
+
+x = 2
+print(x ** -2)
+
+x = 3
+x **= -2
+print(x)