Bug report
Bug description:
The f-string f'{1:{name}}' has a extra Constant(value='') in the format_spec part in 3.12, which is not part of the AST in 3.11. This has also an effect on the generated bytecode.
import ast
import dis
print(ast.dump(ast.parse("f'{1:{name}}'"),indent=2))
dis.dis(compile("f'{1:{name}}'","<string>","exec"))output (Python 3.12.0):
Module(
body=[
Expr(
value=JoinedStr(
values=[
FormattedValue(
value=Constant(value=1),
conversion=-1,
format_spec=JoinedStr(
values=[
FormattedValue(
value=Name(id='name', ctx=Load()),
conversion=-1),
Constant(value='')]))]))], # <-- extra Constant
type_ignores=[])
0 0 RESUME 0
1 2 LOAD_CONST 0 (1)
4 LOAD_NAME 0 (name)
6 FORMAT_VALUE 0
8 LOAD_CONST 1 ('') # <-- extra LOAD_CONST
10 BUILD_STRING 2 # <-- extra BUILD_STRING
12 FORMAT_VALUE 4 (with format)
14 POP_TOP
16 RETURN_CONST 2 (None)output (Python 3.11.3):
Module(
body=[
Expr(
value=JoinedStr(
values=[
FormattedValue(
value=Constant(value=1),
conversion=-1,
format_spec=JoinedStr(
values=[
FormattedValue(
value=Name(id='name', ctx=Load()),
conversion=-1)]))]))],
type_ignores=[])
0 0 RESUME 0
1 2 LOAD_CONST 0 (1)
4 LOAD_NAME 0 (name)
6 FORMAT_VALUE 0
8 FORMAT_VALUE 4 (with format)
10 POP_TOP
12 LOAD_CONST 1 (None)
14 RETURN_VALUECPython versions tested on:
3.12
Operating systems tested on:
Linux
Linked PRs
Bug report
Bug description:
The f-string
f'{1:{name}}'has a extraConstant(value='')in the format_spec part in 3.12, which is not part of the AST in 3.11. This has also an effect on the generated bytecode.output (Python 3.12.0):
output (Python 3.11.3):
CPython versions tested on:
3.12
Operating systems tested on:
Linux
Linked PRs