tests: Make tests work on targets without float support.

tests/basics/op_precedence.py

@@ -37,7 +37,7 @@ print(2 + 2 * 2)
 # BAD: (-2)**2 = 4
 print(-2**2)
 # OK: 2**(-1) = 0.5
-print(2**-1)
+print(2**-0)
 
 # (expr...)
 print((2 + 2) * 2)

tests/extmod/urandom_extra.py

@@ -67,13 +67,3 @@ try:
     random.choice([])
 except IndexError:
     print('IndexError')
-
-print('random')
-for i in range(50):
-    assert 0 <= random.random() < 1
-
-print('uniform')
-for i in range(50):
-    assert 0 <= random.uniform(0, 4) <= 4
-    assert 2 <= random.uniform(2, 6) <= 6
-    assert -2 <= random.uniform(-2, 2) <= 2

tests/extmod/urandom_extra_float.py

@@ -0,0 +1,24 @@
+try:
+    import urandom as random
+except ImportError:
+    try:
+        import random
+    except ImportError:
+        print("SKIP")
+        raise SystemExit
+
+try:
+    random.randint
+except AttributeError:
+    print('SKIP')
+    raise SystemExit
+
+print('random')
+for i in range(50):
+    assert 0 <= random.random() < 1
+
+print('uniform')
+for i in range(50):
+    assert 0 <= random.uniform(0, 4) <= 4
+    assert 2 <= random.uniform(2, 6) <= 6
+    assert -2 <= random.uniform(-2, 2) <= 2

tests/misc/print_exception.py

@@ -31,7 +31,7 @@ def print_exc(e):
 
 # basic exception message
 try:
-    1/0
+    raise Exception('msg')
 except Exception as e:
     print('caught')
     print_exc(e)
@@ -40,7 +40,7 @@ except Exception as e:
 def f():
     g()
 def g():
-    2/0
+    raise Exception('fail')
 try:
     f()
 except Exception as e:

tests/run-tests

@@ -277,8 +277,12 @@ def run_tests(pyb, tests, args, base_path="."):
         skip_tests.add('thread/stress_recurse.py') # has reliability issues
 
     if upy_float_precision == 0:
+        skip_tests.add('extmod/uctypes_le_float.py')
+        skip_tests.add('extmod/uctypes_native_float.py')
+        skip_tests.add('extmod/uctypes_sizeof_float.py')
         skip_tests.add('extmod/ujson_dumps_float.py')
         skip_tests.add('extmod/ujson_loads_float.py')
+        skip_tests.add('extmod/urandom_extra_float.py')
         skip_tests.add('misc/rge_sm.py')
     if upy_float_precision < 32:
         skip_tests.add('float/float2int_intbig.py') # requires fp32, there's float2int_fp30_intbig.py instead