Merge pull request #40 from trailofbits/plist

Add experimental support for diffing Apple plists

README.md

@@ -5,7 +5,7 @@
 [![Slack Status](https://empireslacking.herokuapp.com/badge.svg)](https://empireslacking.herokuapp.com)
 
 Graphtage is a commandline utility and [underlying library](https://trailofbits.github.io/graphtage/latest/library.html)
-for semantically comparing and merging tree-like structures, such as JSON, XML, HTML, YAML, and CSS files. Its name is a
+for semantically comparing and merging tree-like structures, such as JSON, XML, HTML, YAML, plist, and CSS files. Its name is a
 portmanteau of “graph” and “graftage”—the latter being the horticultural practice of joining two trees together such
 that they grow as one.
 

docs/_templates/layout.html

@@ -17,6 +17,7 @@
             {% endfor %}
           {% else %}
             <dd><a href="/graphtage/latest">latest</a></dd>
+            <dd><a href="/graphtage/v0.2.5">0.2.5</a></dd>
             <dd><a href="/graphtage/v0.2.4">0.2.4</a></dd>
             <dd><a href="/graphtage/v0.2.3">0.2.3</a></dd>
             <dd><a href="/graphtage/v0.2.2">0.2.2</a></dd>

graphtage/__init__.py

@@ -7,7 +7,7 @@
 from .version import __version__, VERSION_STRING
 from . import bounds, edits, expressions, fibonacci, formatter, levenshtein, matching, printer, \
                                                                search, sequences, tree, utils
-from . import csv, json, xml, yaml
+from . import csv, json, xml, yaml, plist
 
 import inspect
 

graphtage/__main__.py

@@ -241,6 +241,8 @@ def printer_type(*pos_args, **kwargs):
         mimetypes.suffix_map['.yaml'] = '.yml'
     if '.json5' not in mimetypes.types_map:
         mimetypes.add_type('application/json5', '.json5')
+    if '.plist' not in mimetypes.types_map:
+        mimetypes.add_type('application/x-plist', '.plist')
 
     if args.from_mime is not None:
         from_mime = args.from_mime

graphtage/plist.py

@@ -0,0 +1,171 @@
+"""A :class:`graphtage.Filetype` for parsing, diffing, and rendering Apple plist files."""
+import os
+from xml.parsers.expat import ExpatError
+from typing import Optional, Tuple, Union
+
+from plistlib import dumps, load
+
+from . import json
+from .edits import Edit, EditCollection, Match
+from .graphtage import BoolNode, BuildOptions, Filetype, FloatNode, KeyValuePairNode, IntegerNode, LeafNode, StringNode
+from .printer import Printer
+from .sequences import SequenceFormatter, SequenceNode
+from .tree import ContainerNode, GraphtageFormatter, TreeNode
+
+
+class PLISTNode(ContainerNode):
+    def __init__(self, root: TreeNode):
+        self.root: TreeNode = root
+
+    def to_obj(self):
+        return self.root.to_obj()
+
+    def edits(self, node: 'TreeNode') -> Edit:
+        if isinstance(node, PLISTNode):
+            return EditCollection(
+                from_node=self,
+                to_node=node,
+                edits=iter((
+                    Match(self, node, 0),
+                    self.root.edits(node.root)
+                )),
+                collection=list,
+                add_to_collection=list.append,
+                explode_edits=False
+            )
+        return self.root.edits(node)
+
+    def calculate_total_size(self) -> int:
+        return self.root.calculate_total_size()
+
+    def print(self, printer: Printer):
+        printer.write(PLIST_HEADER)
+        self.root.print(printer)
+        printer.write(PLIST_FOOTER)
+
+    def __iter__(self):
+        yield self.root
+
+    def __len__(self) -> int:
+        return 1
+
+
+def build_tree(path: str, options: Optional[BuildOptions] = None, *args, **kwargs) -> PLISTNode:
+    """Constructs a PLIST tree from an PLIST file."""
+    with open(path, "rb") as stream:
+        data = load(stream)
+        return PLISTNode(json.build_tree(data, options=options, *args, **kwargs))
+
+
+class PLISTSequenceFormatter(SequenceFormatter):
+    is_partial = True
+
+    def __init__(self):
+        super().__init__('', '', '')
+
+    def print_SequenceNode(self, printer: Printer, node: SequenceNode):
+        self.parent.print(printer, node)
+
+    def print_ListNode(self, printer: Printer, *args, **kwargs):
+        printer.write("<array>")
+        super().print_SequenceNode(printer, *args, **kwargs)
+        printer.write("</array>")
+
+    def print_MultiSetNode(self, printer: Printer, *args, **kwargs):
+        printer.write("<dict>")
+        super().print_SequenceNode(printer, *args, **kwargs)
+        printer.write("</dict>")
+
+    def print_KeyValuePairNode(self, printer: Printer, node: KeyValuePairNode):
+        printer.write("<key>")
+        if isinstance(node.key, StringNode):
+            printer.write(node.key.object)
+        else:
+            self.print(printer, node.key)
+        printer.write("</key>")
+        printer.newline()
+        self.print(printer, node.value)
+
+    print_MappingNode = print_MultiSetNode
+
+
+def _plist_header_footer() -> Tuple[str, str]:
+    string = "1234567890"
+    encoded = dumps(string).decode("utf-8")
+    expected = f"<string>{string}</string>"
+    body_offset = encoded.find(expected)
+    if body_offset <= 0:
+        raise ValueError("Unexpected plist encoding!")
+    return encoded[:body_offset], encoded[body_offset+len(expected):]
+
+
+PLIST_HEADER: str
+PLIST_FOOTER: str
+PLIST_HEADER, PLIST_FOOTER = _plist_header_footer()
+
+
+class PLISTFormatter(GraphtageFormatter):
+    sub_format_types = [PLISTSequenceFormatter]
+
+    def print(self, printer: Printer, *args, **kwargs):
+        # PLIST uses an eight-space indent
+        printer.indent_str = " " * 8
+        super().print(printer, *args, **kwargs)
+
+    @staticmethod
+    def write_obj(printer: Printer, obj):
+        encoded = dumps(obj).decode("utf-8")
+        printer.write(encoded[len(PLIST_HEADER):-len(PLIST_FOOTER)])
+
+    def print_StringNode(self, printer: Printer, node: StringNode):
+        printer.write(f"<string>{node.object}</string>")
+
+    def print_IntegerNode(self, printer: Printer, node: IntegerNode):
+        printer.write(f"<integer>{node.object}</integer>")
+
+    def print_FloatNode(self, printer: Printer, node: FloatNode):
+        printer.write(f"<real>{node.object}</real>")
+
+    def print_BoolNode(self, printer, node: BoolNode):
+        if node.object:
+            printer.write("<true />")
+        else:
+            printer.write("<false />")
+
+    def print_LeafNode(self, printer: Printer, node: LeafNode):
+        self.write_obj(printer, node.object)
+
+    def print_PLISTNode(self, printer: Printer, node: PLISTNode):
+        printer.write(PLIST_HEADER)
+        self.print(printer, node.root)
+        printer.write(PLIST_FOOTER)
+
+
+class PLIST(Filetype):
+    """The Apple PLIST filetype."""
+    def __init__(self):
+        """Initializes the PLIST file type.
+
+        By default, PLIST associates itself with the "plist" and "application/x-plist" MIME types.
+
+        """
+        super().__init__(
+            'plist',
+            'application/x-plist'
+        )
+
+    def build_tree(self, path: str, options: Optional[BuildOptions] = None) -> TreeNode:
+        tree = build_tree(path=path, options=options)
+        for node in tree.dfs():
+            if isinstance(node, StringNode):
+                node.quoted = False
+        return tree
+
+    def build_tree_handling_errors(self, path: str, options: Optional[BuildOptions] = None) -> Union[str, TreeNode]:
+        try:
+            return self.build_tree(path=path, options=options)
+        except ExpatError as ee:
+            return f'Error parsing {os.path.basename(path)}: {ee})'
+
+    def get_default_formatter(self) -> PLISTFormatter:
+        return PLISTFormatter.DEFAULT_INSTANCE

graphtage/version.py

@@ -48,7 +48,7 @@ def git_branch() -> Optional[str]:
         return None
 
 
-DEV_BUILD = True
+DEV_BUILD = False
 """Sets whether this build is a development build.
 
 This should only be set to :const:`False` to coincide with a release. It should *always* be :const:`False` before

test/test_formatting.py

@@ -1,5 +1,6 @@
 import csv
 import json
+import plistlib
 import random
 from functools import partial, wraps
 from io import StringIO
@@ -44,8 +45,10 @@ def wrapper(self: 'TestFormatting'):
         formatter = filetype.get_default_formatter()
 
         for _ in trange(iterations):
-            orig_obj, str_representation = test_func(self)
-            with graphtage.utils.Tempfile(str_representation.encode('utf-8')) as t:
+            orig_obj, representation = test_func(self)
+            if isinstance(representation, str):
+                representation = representation.encode("utf-8")
+            with graphtage.utils.Tempfile(representation) as t:
                 tree = filetype.build_tree(t)
                 stream = StringIO()
                 printer = graphtage.printer.Printer(out_stream=stream, ansi_color=False)
@@ -58,7 +61,7 @@ def wrapper(self: 'TestFormatting'):
                     self.fail(f"""{filetype_name.upper()} decode error {e}: Original object:
 {orig_obj!r}
 Expected format:
-{str_representation!s}
+{representation.decode("utf-8")}
 Actual format:
 {formatted_str!s}""")
             if test_equality:
@@ -245,3 +248,8 @@ def test_yaml_formatting(self):
         s = StringIO()
         yaml.dump(orig_obj, s, Dumper=graphtage.yaml.Dumper)
         return orig_obj, s.getvalue()
+
+    @filetype_test(test_equality=False)
+    def test_plist_formatting(self):
+        orig_obj = TestFormatting.make_random_obj(force_string_keys=True, exclude_bytes=frozenset('<>/\n&?|@{}[]'))
+        return orig_obj, plistlib.dumps(orig_obj)