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� @ s d dl mZ dd� Zdd� ZdS )� )�c_astc C s� t | tj�st�t | jtj�s"| S t�g | jj�}d}| jjD ]\}t |tjtj f�rx|j�
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|� q>|| _| S )a� The 'case' statements in a 'switch' come out of parsing with one
child node, so subsequent statements are just tucked to the parent
Compound. Additionally, consecutive (fall-through) case statements
come out messy. This is a peculiarity of the C grammar. The following:
switch (myvar) {
case 10:
k = 10;
p = k + 1;
return 10;
case 20:
case 30:
return 20;
default:
break;
}
Creates this tree (pseudo-dump):
Switch
ID: myvar
Compound:
Case 10:
k = 10
p = k + 1
return 10
Case 20:
Case 30:
return 20
Default:
break
The goal of this transform it to fix this mess, turning it into the
following:
Switch
ID: myvar
Compound:
Case 10:
k = 10
p = k + 1
return 10
Case 20:
Case 30:
return 20
Default:
break
A fixed AST node is returned. The argument may be modified.
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isinstancer ZSwitch�AssertionErrorZstmtZCompoundZcoordZ block_items�Case�Default�append�_extract_nested_case�stmts)Z switch_nodeZ new_compoundZ last_caseZchild� r �/ast_transforms.py�fix_switch_cases
s 3 r
c C s: t | jd tjtjf�r6|�| j�� � t|d |� dS )z� Recursively extract consecutive Case statements that are made nested
by the parser and add them to the stmts_list.
� r N)r r
r r r r �popr )Z case_nodeZ
stmts_listr r r r b s r N)� r r
r r r r r �<module>
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