fix: fix path sum iii json

Author: wislertt

.claude/commands/test-quality-assurance.md

@@ -38,13 +38,15 @@ rm -rf leetcode/{problem_name}_backup
 - ❌ **NEVER modify helpers.py manually** - let regeneration handle it
 - ❌ **NEVER skip ty verification** - this is the main CI issue
 - ❌ **NEVER assume tests will pass** - they may fail if solution is incomplete
+- ❌ **NEVER use `null` in JSON templates** - use `None` for Python None values
 
 ### 4. What to Do
 
 - ✅ **ALWAYS use `bake p-gen -p {problem_name} -f`** for regeneration
 - ✅ **ALWAYS verify ty passes** before considering task complete
 - ✅ **ALWAYS restore original solution** after regeneration
 - ✅ **ALWAYS check JSON template** if ty fails (look for `assert_assert_` bugs)
+- ✅ **ALWAYS use `None` not `null` in JSON templates** for Python None values
 
 ## Test Case Standards
 
@@ -57,6 +59,9 @@ rm -rf leetcode/{problem_name}_backup
 
 ### JSON Format
 
+- **CRITICAL**: Use `None` NOT `null` for Python None values in test cases
+    - JSON templates use `None` directly: `"[1, None, 2]"` NOT `"[1, null, 2]"`
+    - This ensures generated Python code passes linting (ruff/ty check for undefined name `null`)
 - Use single quotes for Python strings: `'hello'` not `"hello"`
 - Follow existing parametrize format
 - Ensure valid Python list syntax in test_cases field
@@ -109,6 +114,20 @@ bake p-gen -p {problem_name} -f
 **Expected**: Tests may fail if solution is incomplete (returns 0 or placeholder)
 **Action**: This is normal - focus on ty passing, not test results
 
+### Issue: `null` vs `None` in JSON Templates
+
+**Cause**: JSON template uses `null` which causes linting errors in generated Python code
+
+- Error: `F821 Undefined name 'null'` from ruff/ty
+- Generated test files contain `null` which is not valid Python
+
+**Solution**: Update JSON template to use `None` instead of `null`
+
+- Change: `"([1, null, 2], 3, 1)"` → `"([1, None, 2], 3, 1)"`
+- This applies to `test_cases` list and `playground_setup` fields
+- After fixing JSON, regenerate with `bake p-gen -p {problem_name} -f`
+- Generated code will now pass linting without manual edits
+
 ## Success Criteria
 
 - ✅ **ty passes** with no errors (CRITICAL for CI)

leetcode/path_sum_iii/README.md

@@ -19,15 +19,15 @@ The path does not need to start or end at the root or a leaf, but it must go dow
 ![Example 1](https://assets.leetcode.com/uploads/2021/04/09/pathsum3-1-tree.jpg)
 
 ```
-Input: root = [10,5,-3,3,2,null,11,3,-2,null,1], targetSum = 8
+Input: root = [10,5,-3,3,2,None,11,3,-2,None,1], targetSum = 8
 Output: 3
 Explanation: The paths that sum to 8 are shown.
 ```
 
 ### Example 2:
 
 ```
-Input: root = [5,4,8,11,null,13,4,7,2,null,null,5,1], targetSum = 22
+Input: root = [5,4,8,11,None,13,4,7,2,None,None,5,1], targetSum = 22
 Output: 3
 ```
 

src/leetcode_py/cli/resources/leetcode/json/problems/path_sum_iii.json

@@ -10,10 +10,10 @@
     "_readme_examples": {
         "list": [
             {
-                "content": "![Example 1](https://assets.leetcode.com/uploads/2021/04/09/pathsum3-1-tree.jpg)\n\n```\nInput: root = [10,5,-3,3,2,null,11,3,-2,null,1], targetSum = 8\nOutput: 3\nExplanation: The paths that sum to 8 are shown.\n```"
+                "content": "![Example 1](https://assets.leetcode.com/uploads/2021/04/09/pathsum3-1-tree.jpg)\n\n```\nInput: root = [10,5,-3,3,2,None,11,3,-2,None,1], targetSum = 8\nOutput: 3\nExplanation: The paths that sum to 8 are shown.\n```"
             },
             {
-                "content": "```\nInput: root = [5,4,8,11,null,13,4,7,2,null,null,5,1], targetSum = 22\nOutput: 3\n```"
+                "content": "```\nInput: root = [5,4,8,11,None,13,4,7,2,None,None,5,1], targetSum = 22\nOutput: 3\n```"
             }
         ]
     },
@@ -47,7 +47,7 @@
         "list": [{ "name": "setup_method", "parameters": "", "body": "self.solution = Solution()" }]
     },
     "playground_imports": "from helpers import run_path_sum, assert_path_sum\nfrom solution import Solution\nfrom leetcode_py import TreeNode",
-    "playground_setup": "# Example test case\nroot_list: list[int | None] = [10,5,-3,3,2,null,11,3,-2,null,1]\ntarget_sum = 8\nexpected = 3",
+    "playground_setup": "# Example test case\nroot_list: list[int | None] = [10,5,-3,3,2,None,11,3,-2,None,1]\ntarget_sum = 8\nexpected = 3",
     "playground_run": "result = run_path_sum(Solution, root_list, target_sum)\nresult",
     "playground_assert": "assert_path_sum(result, expected)",
     "_test_methods": {
@@ -58,28 +58,28 @@
                 "parametrize": "root_list, target_sum, expected",
                 "test_cases": {
                     "list": [
-                        "([10,5,-3,3,2,null,11,3,-2,null,1], 8, 3)",
-                        "([5,4,8,11,null,13,4,7,2,null,null,5,1], 22, 3)",
+                        "([10,5,-3,3,2,None,11,3,-2,None,1], 8, 3)",
+                        "([5,4,8,11,None,13,4,7,2,None,None,5,1], 22, 3)",
                         "([], 1, 0)",
                         "([1], 1, 1)",
                         "([1], 0, 0)",
-                        "([1,2], 3, 2)",
+                        "([1,2], 3, 1)",
                         "([1,2,3], 3, 2)",
                         "([1,2,3], 5, 0)",
                         "([1,-2,3], 1, 1)",
-                        "([1,-2,3], 2, 1)",
+                        "([1,-2,3], 2, 0)",
                         "([1,-2,-3], -3, 1)",
                         "([0,1,1], 1, 4)",
                         "([1,0,1,0,1], 1, 6)",
                         "([0], 0, 1)",
-                        "([-3,-2,1,1,1], -1, 4)"
+                        "([-3,-2,1,1,1], -1, 2)"
                     ]
                 },
                 "body": "        result = run_path_sum(Solution, root_list, target_sum)\n        assert_path_sum(result, expected)"
             }
         ]
     },
-    "playground_test_case": "root_list: list[int | None] = [10,5,-3,3,2,null,11,3,-2,null,1]\ntarget_sum = 8",
+    "playground_test_case": "root_list: list[int | None] = [10,5,-3,3,2,None,11,3,-2,None,1]\ntarget_sum = 8",
     "playground_execution": "result = run_path_sum(Solution, root_list, target_sum)",
     "playground_assertion": "assert_path_sum(result, 3)"
 }