tests/cpydiff: Document that uPy requires space after number+period.

Signed-off-by: Jeff Epler <[email protected]>

Author: jepler

tests/cpydiff/syntax_spaces.py

@@ -1,11 +1,11 @@
 """
 categories: Syntax,Spaces
-description: MicroPython requires spaces between literal numbers and keywords, CPython doesn't
+description: MicroPython requires spaces between literal numbers and keywords or ".", CPython doesn't
 cause: Different parser implementation
 
 MicroPython's tokenizer treats a sequence like ``1and`` as a single token, while CPython treats it as two tokens.
 
-Since CPython 3.11, this syntax causes a ``SyntaxWarning`` for an "invalid literal".
+Since CPython 3.11, when the literal number is followed by a token, this syntax causes a ``SyntaxWarning`` for an "invalid literal". When a literal number is followed by a "." denoting attribute access, CPython does not warn.
 
 workaround: Add a space between the integer literal and the intended next token.
 
@@ -24,3 +24,7 @@
     print(eval("1if 1else 0"))
 except SyntaxError:
     print("Should have worked")
+try:
+    print(eval("0x1.to_bytes(1)"))
+except SyntaxError:
+    print("Should have worked")