Add unit test for reload(); make travis use --assert=reinterp (because assert=rewrite does not work with reload)

.travis.yml

@@ -143,7 +143,8 @@ script:
 
     # Run unit tests
     - start_test "unit tests";
-      PYTHONPATH=. py.test --cov pyqtgraph -sv;
+      # NOTE: tests/test_reload.py breaks without --assert=reinterp|plain
+      PYTHONPATH=. py.test --cov --assert=reinterp pyqtgraph -sv;
       check_output "unit tests";
     - echo "test script finished. Current directory:"
     - pwd

pyqtgraph/tests/test_reload.py

@@ -0,0 +1,74 @@
+import tempfile, os, sys, shutil, atexit
+import pyqtgraph as pg
+import pyqtgraph.reload
+pgpath = os.path.join(os.path.dirname(pg.__file__), '..')
+
+# make temporary directory to write module code
+path = tempfile.mkdtemp()
+sys.path.insert(0, path)
+def cleanup():
+    shutil.rmtree(path)
+atexit.register(cleanup)
+
+
+code = """
+import sys
+sys.path.append('{path}')
+
+import pyqtgraph as pg
+
+class C(pg.QtCore.QObject):
+    sig = pg.QtCore.Signal()
+    def fn(self):
+        print("{msg}")
+
+"""
+
+def test_reload():
+    # write a module
+    mod = os.path.join(path, 'reload_test.py')
+    open(mod, 'w').write(code.format(path=path, msg="C.fn() Version1"))
+
+    # import the new module
+    import reload_test
+
+    c = reload_test.C()
+    c.sig.connect(c.fn)
+    v1 = (reload_test.C, reload_test.C.sig, reload_test.C.fn, reload_test.C.fn.__func__, c.sig, c.fn, c.fn.__func__)
+
+
+
+    # write again and reload
+    open(mod, 'w').write(code.format(path=path, msg="C.fn() Version2"))
+    os.remove(mod+'c')
+    pg.reload.reloadAll(path, debug=True)
+    v2 = (reload_test.C, reload_test.C.sig, reload_test.C.fn, reload_test.C.fn.__func__, c.sig, c.fn, c.fn.__func__)
+
+    assert c.fn.im_class is v2[0]
+    oldcfn = pg.reload.getPreviousVersion(c.fn)
+    assert oldcfn.im_class is v1[0]
+    assert oldcfn.im_func is v1[2].im_func
+    assert oldcfn.im_self is c
+
+
+
+    # write again and reload
+    open(mod, 'w').write(code.format(path=path, msg="C.fn() Version2"))
+    os.remove(mod+'c')
+    pg.reload.reloadAll(path, debug=True)
+    v3 = (reload_test.C, reload_test.C.sig, reload_test.C.fn, reload_test.C.fn.__func__, c.sig, c.fn, c.fn.__func__)
+
+    #for i in range(len(old)):
+        #print id(old[i]), id(new1[i]), id(new2[i]), old[i], new1[i]
+
+    cfn1 = pg.reload.getPreviousVersion(c.fn)
+    cfn2 = pg.reload.getPreviousVersion(cfn1)
+
+    assert cfn1.im_class is v2[0]
+    assert cfn1.im_func is v2[2].im_func
+    assert cfn1.im_self is c
+    assert cfn2.im_class is v1[0]
+    assert cfn2.im_func is v1[2].im_func
+    assert cfn2.im_self is c
+    c.sig.disconnect(cfn2)
+