weekends

Finished
2626
2727
2828def parse(input_string: str) -> SgfTree:
29 pass
29 """
30 Parse an SGF (Smart Game Format) string and return a tree structure of properties.
31
32 Args:
33 input_string: A string containing SGF formatted data
34
35 Returns:
36 SgfTree: A tree structure representing the SGF data
37
38 Raises:
39 ValueError: If the input string is malformed or doesn't conform to SGF format
40 """
41 # Edge Case: Empty input string
42 if not input_string:
43 raise ValueError("tree missing")
44
45 # Edge Case: Input doesn't start with '('
46 if not input_string.startswith('('):
47 raise ValueError("tree missing")
48
49 # Edge Case: Input doesn't end with ')'
50 if not input_string.endswith(')'):
51 raise ValueError("tree missing")
52
53 # Remove the outer parentheses
54 content = input_string[1:-1]
55
56 # Edge Case: Empty content after removing parentheses
57 if not content:
58 raise ValueError("tree with no nodes")
59
60 # Edge Case: Content doesn't start with ';'
61 if not content.startswith(';'):
62 raise ValueError("tree with no nodes")
63
64 return _parse_tree(content)
65
66
67def _parse_tree(content: str) -> SgfTree:
68 """
69 Parse a tree from SGF content.
70
71 Args:
72 content: SGF content string starting with ';'
73
74 Returns:
75 SgfTree: Parsed tree
76 """
77 # Edge Case: Content is just ';'
78 if content == ';':
79 return SgfTree()
80
81 i = 1 # Skip the initial ';'
82 properties = {}
83
84 # Parse properties
85 while i < len(content) and content[i] != '(' and content[i] != ';' and content[i] != ')':
86 # Parse property key
87 key_start = i
88 while i < len(content) and content[i].isalpha():
89 i += 1
90
91 # Edge Case: No key found
92 if i == key_start:
93 raise ValueError("properties without delimiter")
94
95 key = content[key_start:i]
96
97 # Edge Case: Key is not uppercase
98 if not key.isupper():
99 raise ValueError("property must be in uppercase")
100
101 # Parse property values
102 values = []
103
104 # Edge Case: No values after key
105 if i >= len(content) or content[i] != '[':
106 raise ValueError("properties without delimiter")
107
108 while i < len(content) and content[i] == '[':
109 i += 1 # Skip '['
110 value_start = i
111
112 # Parse value, including escaped characters
113 while i < len(content):
114 if content[i] == ']':
115 # Check if this ] is escaped
116 backslash_count = 0
117 j = i - 1
118 while j >= value_start and content[j] == '\\':
119 backslash_count += 1
120 j -= 1
121 # If odd number of backslashes, this ] is escaped
122 if backslash_count % 2 == 1:
123 i += 1 # Skip the escaped ] and continue
124 continue
125 else:
126 break # Found unescaped closing bracket
127 i += 1
128
129 # Edge Case: Unclosed value bracket
130 if i >= len(content) or content[i] != ']':
131 raise ValueError("properties without delimiter")
132
133 value = content[value_start:i]
134 value = _unescape_value(value)
135 values.append(value)
136 i += 1 # Skip ']'
137
138 properties[key] = values
139
140 # Parse children
141 children = []
142
143 while i < len(content) and content[i] == '(':
144 # Find matching parenthesis
145 paren_count = 1
146 start = i + 1
147 i += 1
148
149 while i < len(content) and paren_count > 0:
150 if content[i] == '(':
151 paren_count += 1
152 elif content[i] == ')':
153 paren_count -= 1
154 i += 1
155
156 # Edge Case: Unmatched parenthesis
157 if paren_count != 0:
158 raise ValueError("tree missing")
159
160 child_content = content[start:i-1]
161 child_tree = _parse_tree(child_content)
162 children.append(child_tree)
163
164 # Handle additional nodes in sequence
165 if i < len(content) and content[i] == ';':
166 next_tree = _parse_tree(content[i:])
167 children.append(next_tree)
168
169 return SgfTree(properties, children)
170
171
172def _unescape_value(value: str) -> str:
173 """
174 Unescape SGF text value according to SGF specification.
175
176 Args:
177 value: Escaped SGF text value
178
179 Returns:
180 str: Unescaped text value
181 """
182 result = []
183 i = 0
184 while i < len(value):
185 if value[i] == '\\':
186 i += 1
187 if i < len(value):
188 # If next character is newline, remove both \ and newline
189 if value[i] == '\n':
190 i += 1
191 continue
192 # Any character after \ is inserted as-is
193 result.append(value[i])
194 i += 1
195 else:
196 # Edge Case: Escape at end of string
197 result.append('\\')
198 i += 1
199 else:
200 # Convert whitespace (except newline) to space
201 if value[i] != '\n' and value[i].isspace():
202 result.append(' ')
203 else:
204 result.append(value[i])
205 i += 1
206
207 return ''.join(result)
208# Handled Edge Cases: Empty input string, Input doesn't start with '(', Input doesn't end with ')', Empty content after removing parentheses, Content doesn't start with ';', Content is just ';', No key found, Key is not uppercase, No values after key, Unclosed value bracket, Unmatched parenthesis, Escape at end of string
Test NameStatus
test_escaped_tab_in_property_value_is_converted_to_space
Fail
test_all_lowercase_property
Pass
test_empty_input
Pass
test_escaped_backslash_in_property_value_becomes_just_a_backslash
Pass
test_escaped_closing_bracket_within_property_value_becomes_just_a_closing_bracket
Pass
test_escaped_newline_in_property_value_is_converted_to_nothing_at_all
Pass
test_escaped_t_and_n_in_property_value_are_just_letters_not_whitespace
Pass
test_mixing_various_kinds_of_whitespace_and_escaped_characters_in_property_value
Pass
test_multiple_properties
Pass
test_multiple_property_values
Pass
test_node_without_properties
Pass
test_node_without_tree
Pass
test_opening_bracket_within_property_value_doesn_t_need_to_be_escaped
Pass
test_parentheses_in_property_value_don_t_need_to_be_escaped
Pass
test_properties_without_delimiter
Pass
test_semicolon_in_property_value_doesn_t_need_to_be_escaped
Pass
test_single_node_tree
Pass
test_tree_with_no_nodes
Pass
test_two_child_trees
Pass
test_two_nodes
Pass
test_upper_and_lowercase_property
Pass
test_within_property_values_newlines_remain_as_newlines
Pass
test_within_property_values_whitespace_characters_such_as_tab_are_converted_to_spaces
Pass

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