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# mypy: allow-untyped-defs
from six import ensure_text
from .node import NodeVisitor, ValueNode, ListNode, BinaryExpressionNode
from .parser import atoms, precedence, token_types
atom_names = {v: "@%s" % k for (k,v) in atoms.items()}
named_escapes = {"\a", "\b", "\f", "\n", "\r", "\t", "\v"}
def escape(string, extras=""):
# Assumes input bytes are either UTF8 bytes or unicode.
rv = ""
for c in string:
if c in named_escapes:
rv += c.encode("unicode_escape").decode()
elif c == "\\":
rv += "\\\\"
elif c < '\x20':
rv += "\\x%02x" % ord(c)
elif c in extras:
rv += "\\" + c
else:
rv += c
return ensure_text(rv)
class ManifestSerializer(NodeVisitor):
def __init__(self, skip_empty_data=False):
self.skip_empty_data = skip_empty_data
def serialize(self, root):
self.indent = 2
rv = "\n".join(self.visit(root))
if not rv:
return rv
rv = rv.strip()
if rv[-1] != "\n":
rv = rv + "\n"
return rv
def visit(self, node):
lines = super().visit(node)
comments = [f"#{comment}" for _, comment in node.comments]
# Simply checking if the first line contains '#' is less than ideal; the
# character might be escaped or within a string.
if lines and "#" not in lines[0]:
for i, (token_type, comment) in enumerate(node.comments):
if token_type == token_types.inline_comment:
lines[0] += f" #{comment}"
comments.pop(i)
break
return comments + lines
def visit_DataNode(self, node):
rv = []
if not self.skip_empty_data or node.children:
if node.data:
rv.append("[%s]" % escape(node.data, extras="]"))
indent = self.indent * " "
else:
indent = ""
for child in node.children:
rv.extend("%s%s" % (indent if item else "", item) for item in self.visit(child))
if node.parent:
rv.append("")
return rv
def visit_KeyValueNode(self, node):
rv = [escape(node.data, ":") + ":"]
indent = " " * self.indent
if len(node.children) == 1 and isinstance(node.children[0], (ValueNode, ListNode)):
rv[0] += " %s" % self.visit(node.children[0])[0]
else:
for child in node.children:
rv.extend(indent + line for line in self.visit(child))
return rv
def visit_ListNode(self, node):
rv = ["["]
rv.extend(", ".join(self.visit(child)[0] for child in node.children))
rv.append("]")
return ["".join(rv)]
def visit_ValueNode(self, node):
data = ensure_text(node.data)
if ("#" in data or
data.startswith("if ") or
(isinstance(node.parent, ListNode) and
("," in data or "]" in data))):
if "\"" in data:
quote = "'"
else:
quote = "\""
else:
quote = ""
return [quote + escape(data, extras=quote) + quote]
def visit_AtomNode(self, node):
return [atom_names[node.data]]
def visit_ConditionalNode(self, node):
return ["if %s: %s" % tuple(self.visit(item)[0] for item in node.children)]
def visit_StringNode(self, node):
rv = ["\"%s\"" % escape(node.data, extras="\"")]
for child in node.children:
rv[0] += self.visit(child)[0]
return rv
def visit_NumberNode(self, node):
return [ensure_text(node.data)]
def visit_VariableNode(self, node):
rv = escape(node.data)
for child in node.children:
rv += self.visit(child)
return [rv]
def visit_IndexNode(self, node):
assert len(node.children) == 1
return ["[%s]" % self.visit(node.children[0])[0]]
def visit_UnaryExpressionNode(self, node):
children = []
for child in node.children:
child_str = self.visit(child)[0]
if isinstance(child, BinaryExpressionNode):
child_str = "(%s)" % child_str
children.append(child_str)
return [" ".join(children)]
def visit_BinaryExpressionNode(self, node):
assert len(node.children) == 3
children = []
for child_index in [1, 0, 2]:
child = node.children[child_index]
child_str = self.visit(child)[0]
if (isinstance(child, BinaryExpressionNode) and
precedence(node.children[0]) < precedence(child.children[0])):
child_str = "(%s)" % child_str
children.append(child_str)
return [" ".join(children)]
def visit_UnaryOperatorNode(self, node):
return [ensure_text(node.data)]
def visit_BinaryOperatorNode(self, node):
return [ensure_text(node.data)]
def serialize(tree, *args, **kwargs):
s = ManifestSerializer(*args, **kwargs)
return s.serialize(tree)