prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
   similar variables detector is extremely slow
   This detector makes up the majority of runtime on large codebases
  ```
  ncalls  tottime  percall  cumtime  percall filename:lineno(function)
          1    0.000    0.000   41.286   41.286 /Users/alpharush/tob/slither/slither/__main__.py:81(process_all)
          1    0.000    0.000   39.059   39.059 /Users/alpharush/tob/slither/slither/__main__.py:58(process_single)
          1    0.000    0.000   33.319   33.319 /Users/alpharush/tob/slither/slither/__main__.py:111(_process)
          1    0.000    0.000   33.317   33.317 /Users/alpharush/tob/slither/slither/slither.py:198(run_detectors)
          1    0.000    0.000   33.317   33.317 /Users/alpharush/tob/slither/slither/slither.py:204(<listcomp>)
         84    0.001    0.000   33.317    0.397 /Users/alpharush/tob/slither/slither/detectors/abstract_detector.py:176(detect)
          1    0.000    0.000   31.215   31.215 /Users/alpharush/tob/slither/slither/detectors/variables/similar_variables.py:72(_detect)
  
  ```
  https://github.com/crytic/slither/blob/master/slither/detectors/variables/similar_variables.py#L63-L66
  
  </issue>
  <code>
  [start of slither/detectors/variables/similar_variables.py]
  1 """
  2 Check for state variables too similar
  3 Do not check contract inheritance
  4 """
  5 import difflib
  6 from typing import List, Set, Tuple
  7 
  8 from slither.core.declarations.contract import Contract
  9 from slither.core.variables.local_variable import LocalVariable
  10 from slither.detectors.abstract_detector import (
  11     AbstractDetector,
  12     DetectorClassification,
  13     DETECTOR_INFO,
  14 )
  15 from slither.utils.output import Output
  16 
  17 
  18 class SimilarVarsDetection(AbstractDetector):
  19     """
  20     Variable similar detector
  21     """
  22 
  23     ARGUMENT = "similar-names"
  24     HELP = "Variable names are too similar"
  25     IMPACT = DetectorClassification.INFORMATIONAL
  26     CONFIDENCE = DetectorClassification.MEDIUM
  27 
  28     WIKI = (
  29         "https://github.com/crytic/slither/wiki/Detector-Documentation#variable-names-too-similar"
  30     )
  31 
  32     WIKI_TITLE = "Variable names too similar"
  33     WIKI_DESCRIPTION = "Detect variables with names that are too similar."
  34     WIKI_EXPLOIT_SCENARIO = "Bob uses several variables with similar names. As a result, his code is difficult to review."
  35     WIKI_RECOMMENDATION = "Prevent variables from having similar names."
  36 
  37     @staticmethod
  38     def similar(seq1: str, seq2: str) -> bool:
  39         """Test the name similarity
  40 
  41         Two name are similar if difflib.SequenceMatcher on the lowercase
  42         version of the name is greater than 0.90
  43         See: https://docs.python.org/2/library/difflib.html
  44         Args:
  45             seq1 (str): first name
  46             seq2 (str): second name
  47         Returns:
  48             bool: true if names are similar
  49         """
  50         if len(seq1) != len(seq2):
  51             return False
  52         val = difflib.SequenceMatcher(a=seq1.lower(), b=seq2.lower()).ratio()
  53         ret = val > 0.90
  54         return ret
  55 
  56     @staticmethod
  57     def detect_sim(contract: Contract) -> Set[Tuple[LocalVariable, LocalVariable]]:
  58         """Detect variables with similar name
  59 
  60         Returns:
  61             bool: true if variables have similar name
  62         """
  63         all_var = [x.variables for x in contract.functions]
  64         all_var = [x for l in all_var for x in l]
  65 
  66         contract_var = contract.variables
  67 
  68         all_var = set(all_var + contract_var)
  69 
  70         ret = []
  71         for v1 in all_var:
  72             for v2 in all_var:
  73                 if v1.name.lower() != v2.name.lower():
  74                     if SimilarVarsDetection.similar(v1.name, v2.name):
  75                         if (v2, v1) not in ret:
  76                             ret.append((v1, v2))
  77 
  78         return set(ret)
  79 
  80     def _detect(self) -> List[Output]:
  81         """Detect similar variables name
  82 
  83         Returns:
  84             list: {'vuln', 'filename,'contract','vars'}
  85         """
  86         results = []
  87         for c in self.contracts:
  88             allVars = self.detect_sim(c)
  89             if allVars:
  90                 for (v1, v2) in sorted(allVars, key=lambda x: (x[0].name, x[1].name)):
  91                     v_left = v1 if v1.name < v2.name else v2
  92                     v_right = v2 if v_left == v1 else v1
  93                     info: DETECTOR_INFO = [
  94                         "Variable ",
  95                         v_left,
  96                         " is too similar to ",
  97                         v_right,
  98                         "\n",
  99                     ]
  100                     json = self.generate_result(info)
  101                     results.append(json)
  102         return results
  103
  [end of slither/detectors/variables/similar_variables.py]
  </code>
  
  I need you to solve this issue by generating a single patch file that I can apply directly to this repository using git apply. Please respond with a single patch file in the following format.
  <patch>
  diff --git a/file.py b/file.py
  --- a/file.py
  +++ b/file.py
  @@ -1,27 +1,35 @@
   def euclidean(a, b):
  -    while b:
  -        a, b = b, a % b
  -    return a
  +    if b == 0:
  +        return a
  +    return euclidean(b, a % b)
   
   
   def bresenham(x0, y0, x1, y1):
       points = []
       dx = abs(x1 - x0)
       dy = abs(y1 - y0)
  -    sx = 1 if x0 < x1 else -1
  -    sy = 1 if y0 < y1 else -1
  -    err = dx - dy
  +    x, y = x0, y0
  +    sx = -1 if x0 > x1 else 1
  +    sy = -1 if y0 > y1 else 1
   
  -    while True:
  -        points.append((x0, y0))
  -        if x0 == x1 and y0 == y1:
  -            break
  -        e2 = 2 * err
  -        if e2 > -dy:
  -            err -= dy
  -            x0 += sx
  -        if e2 < dx:
  -            err += dx
  -            y0 += sy
  +    if dx > dy:
  +        err = dx / 2.0
  +        while x != x1:
  +            points.append((x, y))
  +            err -= dy
  +            if err < 0:
  +                y += sy
  +                err += dx
  +            x += sx
  +    else:
  +        err = dy / 2.0
  +        while y != y1:
  +            points.append((x, y))
  +            err -= dx
  +            if err < 0:
  +                x += sx
  +                err += dy
  +            y += sy
  +
  +    points.append((x, y))
       return points
  
  </patch>
golden_diff: diff --git a/slither/detectors/variables/similar_variables.py b/slither/detectors/variables/similar_variables.py
  --- a/slither/detectors/variables/similar_variables.py
  +++ b/slither/detectors/variables/similar_variables.py
  @@ -65,12 +65,16 @@
   
           contract_var = contract.variables
   
  -        all_var = set(all_var + contract_var)
  +        all_var = list(set(all_var + contract_var))
   
           ret = []
  -        for v1 in all_var:
  -            for v2 in all_var:
  -                if v1.name.lower() != v2.name.lower():
  +        # pylint: disable=consider-using-enumerate
  +        for i in range(len(all_var)):
  +            v1 = all_var[i]
  +            _v1_name_lower = v1.name.lower()
  +            for j in range(i, len(all_var)):
  +                v2 = all_var[j]
  +                if _v1_name_lower != v2.name.lower():
                       if SimilarVarsDetection.similar(v1.name, v2.name):
                           if (v2, v1) not in ret:
                               ret.append((v1, v2))
  
verification_info: {"golden_diff": "diff --git a/slither/detectors/variables/similar_variables.py b/slither/detectors/variables/similar_variables.py\n--- a/slither/detectors/variables/similar_variables.py\n+++ b/slither/detectors/variables/similar_variables.py\n@@ -65,12 +65,16 @@\n \n         contract_var = contract.variables\n \n-        all_var = set(all_var + contract_var)\n+        all_var = list(set(all_var + contract_var))\n \n         ret = []\n-        for v1 in all_var:\n-            for v2 in all_var:\n-                if v1.name.lower() != v2.name.lower():\n+        # pylint: disable=consider-using-enumerate\n+        for i in range(len(all_var)):\n+            v1 = all_var[i]\n+            _v1_name_lower = v1.name.lower()\n+            for j in range(i, len(all_var)):\n+                v2 = all_var[j]\n+                if _v1_name_lower != v2.name.lower():\n                     if SimilarVarsDetection.similar(v1.name, v2.name):\n                         if (v2, v1) not in ret:\n                             ret.append((v1, v2))\n", "issue": " similar variables detector is extremely slow\n This detector makes up the majority of runtime on large codebases\r\n```\r\nncalls  tottime  percall  cumtime  percall filename:lineno(function)\r\n        1    0.000    0.000   41.286   41.286 /Users/alpharush/tob/slither/slither/__main__.py:81(process_all)\r\n        1    0.000    0.000   39.059   39.059 /Users/alpharush/tob/slither/slither/__main__.py:58(process_single)\r\n        1    0.000    0.000   33.319   33.319 /Users/alpharush/tob/slither/slither/__main__.py:111(_process)\r\n        1    0.000    0.000   33.317   33.317 /Users/alpharush/tob/slither/slither/slither.py:198(run_detectors)\r\n        1    0.000    0.000   33.317   33.317 /Users/alpharush/tob/slither/slither/slither.py:204(<listcomp>)\r\n       84    0.001    0.000   33.317    0.397 /Users/alpharush/tob/slither/slither/detectors/abstract_detector.py:176(detect)\r\n        1    0.000    0.000   31.215   31.215 /Users/alpharush/tob/slither/slither/detectors/variables/similar_variables.py:72(_detect)\r\n\r\n```\r\nhttps://github.com/crytic/slither/blob/master/slither/detectors/variables/similar_variables.py#L63-L66\n", "before_files": [{"content": "\"\"\"\nCheck for state variables too similar\nDo not check contract inheritance\n\"\"\"\nimport difflib\nfrom typing import List, Set, Tuple\n\nfrom slither.core.declarations.contract import Contract\nfrom slither.core.variables.local_variable import LocalVariable\nfrom slither.detectors.abstract_detector import (\n    AbstractDetector,\n    DetectorClassification,\n    DETECTOR_INFO,\n)\nfrom slither.utils.output import Output\n\n\nclass SimilarVarsDetection(AbstractDetector):\n    \"\"\"\n    Variable similar detector\n    \"\"\"\n\n    ARGUMENT = \"similar-names\"\n    HELP = \"Variable names are too similar\"\n    IMPACT = DetectorClassification.INFORMATIONAL\n    CONFIDENCE = DetectorClassification.MEDIUM\n\n    WIKI = (\n        \"https://github.com/crytic/slither/wiki/Detector-Documentation#variable-names-too-similar\"\n    )\n\n    WIKI_TITLE = \"Variable names too similar\"\n    WIKI_DESCRIPTION = \"Detect variables with names that are too similar.\"\n    WIKI_EXPLOIT_SCENARIO = \"Bob uses several variables with similar names. As a result, his code is difficult to review.\"\n    WIKI_RECOMMENDATION = \"Prevent variables from having similar names.\"\n\n    @staticmethod\n    def similar(seq1: str, seq2: str) -> bool:\n        \"\"\"Test the name similarity\n\n        Two name are similar if difflib.SequenceMatcher on the lowercase\n        version of the name is greater than 0.90\n        See: https://docs.python.org/2/library/difflib.html\n        Args:\n            seq1 (str): first name\n            seq2 (str): second name\n        Returns:\n            bool: true if names are similar\n        \"\"\"\n        if len(seq1) != len(seq2):\n            return False\n        val = difflib.SequenceMatcher(a=seq1.lower(), b=seq2.lower()).ratio()\n        ret = val > 0.90\n        return ret\n\n    @staticmethod\n    def detect_sim(contract: Contract) -> Set[Tuple[LocalVariable, LocalVariable]]:\n        \"\"\"Detect variables with similar name\n\n        Returns:\n            bool: true if variables have similar name\n        \"\"\"\n        all_var = [x.variables for x in contract.functions]\n        all_var = [x for l in all_var for x in l]\n\n        contract_var = contract.variables\n\n        all_var = set(all_var + contract_var)\n\n        ret = []\n        for v1 in all_var:\n            for v2 in all_var:\n                if v1.name.lower() != v2.name.lower():\n                    if SimilarVarsDetection.similar(v1.name, v2.name):\n                        if (v2, v1) not in ret:\n                            ret.append((v1, v2))\n\n        return set(ret)\n\n    def _detect(self) -> List[Output]:\n        \"\"\"Detect similar variables name\n\n        Returns:\n            list: {'vuln', 'filename,'contract','vars'}\n        \"\"\"\n        results = []\n        for c in self.contracts:\n            allVars = self.detect_sim(c)\n            if allVars:\n                for (v1, v2) in sorted(allVars, key=lambda x: (x[0].name, x[1].name)):\n                    v_left = v1 if v1.name < v2.name else v2\n                    v_right = v2 if v_left == v1 else v1\n                    info: DETECTOR_INFO = [\n                        \"Variable \",\n                        v_left,\n                        \" is too similar to \",\n                        v_right,\n                        \"\\n\",\n                    ]\n                    json = self.generate_result(info)\n                    results.append(json)\n        return results\n", "path": "slither/detectors/variables/similar_variables.py"}]}