tests/cpydiff: Add test of underscore-in-literals.

Signed-off-by: Jeff Epler <jepler@gmail.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/tests/cpydiff/syntax_literal_underscore.py b/tests/cpydiff/syntax_literal_underscore.py
new file mode 100644
index 000000000..4b1406e9f
--- /dev/null
+++ b/tests/cpydiff/syntax_literal_underscore.py
@@ -0,0 +1,19 @@
+"""
+categories: Syntax,Literals
+description: MicroPython accepts underscores in numeric literals where CPython doesn't
+cause: Different parser implementation
+
+MicroPython's tokenizer ignores underscores in numeric literals, while CPython
+rejects multiple consecutive underscores and underscores after the last digit.
+
+workaround: Remove the underscores not accepted by CPython.
+"""
+
+try:
+    print(eval("1__1"))
+except SyntaxError:
+    print("Should not work")
+try:
+    print(eval("1_"))
+except SyntaxError:
+    print("Should not work")