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NilPy: a class body of only pass fails to parse

Found while testing feature-nilpy-aggregate-builtins's type(x).__name__ addition (an empty exception subclass was the natural first thing to try it on).

class MyErr(Exception):
    pass



Expected: def, but got: pass (Kind: 1, Line: 2)
pascal26:2: error: unexpected token

Not specific to inheriting Exception — a plain class Empty: pass hits the same error.

Cause

PyParseClass's body loop (pyparser.inc) has a case for a docstring, a class-attribute line, a @decorator, and a nested class; every other leading token falls into an unconditional PyParseMethod(ci) call, which immediately does Expect(tkFunction, 'def'). A bare pass — the idiomatic empty body — has no case of its own, unlike every OTHER pass site in the grammar (the statement-level one already skips it).

Fix

Gave the class-body loop the same pass-skip the statement level already has.

Gate

make test-nilpy + self-host byte-identical, plus a .npy covering an empty class X(Exception): pass (raised, caught, type(e).__name__ read back) and a plain class Empty: pass (constructed), diffed against CPython.

Resolved

Fixed and gated green — commit f3db58864a3c20b0015c16e0cabe6fdecc0380c9. Regression: test/test_nilpy_class_pass_body.npy.

Log