tests/basics: Add tests for try-except-else and try-except-else-finally.

tests/basics/try_else.py

+# test try-else statement
+
+# base case
+try:
+    print(1)
+except:
+    print(2)
+else:
+    print(3)
+
+# basic case that should skip else
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+else:
+    print(3)
+
+# uncaught exception should skip else
+try:
+    try:
+        print(1)
+        raise ValueError
+    except TypeError:
+        print(2)
+    else:
+        print(3)
+except:
+    print('caught')
+
+# nested within outer try
+try:
+    print(1)
+    try:
+        print(2)
+        raise Exception
+    except:
+        print(3)
+    else:
+        print(4)
+except:
+    print(5)
+else:
+    print(6)
+
+# nested within outer except, one else should be skipped
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+    try:
+        print(3)
+    except:
+        print(4)
+    else:
+        print(5)
+else:
+    print(6)
+
+# nested within outer except, both else should be skipped
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+    try:
+        print(3)
+        raise Exception
+    except:
+        print(4)
+    else:
+        print(5)
+else:
+    print(6)

tests/basics/try_else_finally.py

+# test try-else-finally statement
+
+# base case
+try:
+    print(1)
+except:
+    print(2)
+else:
+    print(3)
+finally:
+    print(4)
+
+# basic case that should skip else
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+else:
+    print(3)
+finally:
+    print(4)
+
+# uncaught exception should skip else
+try:
+    try:
+        print(1)
+        raise ValueError
+    except TypeError:
+        print(2)
+    else:
+        print(3)
+    finally:
+        print(4)
+except:
+    print('caught')
+
+# nested within outer try
+try:
+    print(1)
+    try:
+        print(2)
+        raise Exception
+    except:
+        print(3)
+    else:
+        print(4)
+    finally:
+        print(5)
+except:
+    print(6)
+else:
+    print(7)
+finally:
+    print(8)
+
+# nested within outer except, one else should be skipped
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+    try:
+        print(3)
+    except:
+        print(4)
+    else:
+        print(5)
+    finally:
+        print(6)
+else:
+    print(7)
+finally:
+    print(8)
+
+# nested within outer except, both else should be skipped
+try:
+    print(1)
+    raise Exception
+except:
+    print(2)
+    try:
+        print(3)
+        raise Exception
+    except:
+        print(4)
+    else:
+        print(5)
+    finally:
+        print(6)
+else:
+    print(7)
+finally:
+    print(8)