Fix constraints bug.

Add constraints unittests.
Update invalid words.

wordle.py

@@ -27,7 +27,9 @@ _wordle_dictionary = set()
 
 _invalid_words = set(['staia', 'erept', 'boily', 'bolty', 'pindy', 'hyrse', 'hirse', 'retan', 'sisel',
                       'skeel', 'telae', 'genae', 'beata', 'beala', 'macco', 'beele', 'divet', 'vedet',
-                      'stail', 'roter', 'fikie', 'muang', 'nurry'])
+                      'stail', 'roter', 'fikie', 'muang', 'nurry', 'arara', 'araru', 'araua', 'arawa',
+                      'mitra', 'gotra', 'whaly', 'whalm', 'doray', 'korah', 'caroa', 'carlo', 'carot',
+                      'carum', 'theet', 'tebet', 'ghole', 'odell'])
 
 
 def dictionary():
@@ -152,36 +154,39 @@ def scored_words(wordle_dictionary=dictionary()):
 
 
 class Constraints():
-    correct = [None] * WORDLE_LENGTH  # Letter is None, or known.
-    # Sets of letters that must be elsewhere
-    move = defaultdict(set)
-    min = defaultdict(int)
-    exact = set()
+
+    def __init__(self):
+        # Array of known letters in result with None for unknown.
+        self.correct = [None] * WORDLE_LENGTH
+        # Array with per-letter sets of known bad letters.
+        self.incorrect = [set() for _ in range(WORDLE_LENGTH)]
+        # Dict of letter -> int with minimum required count of letter in word.
+        self.count = defaultdict(int)
+        # If letter is present in set, value in min is both min and max.
+        self.exact = set()
 
     # List of LetterResult values.
     def update_graded(self, guess, grade):
 
         guess = guess.lower()
 
-        new_min = defaultdict(int)
-        new_exact = set()
+        new_count = defaultdict(int)
 
         for i, letter in enumerate(guess):
             match grade[i]:
                 case LetterResult.CORRECT:
                     self.correct[i] = letter
-                    new_min[letter] += 1
+                    new_count[letter] += 1
                 case LetterResult.MOVE:
-                    self.move[letter].add(i)
-                    new_min[letter] += 1
+                    self.incorrect[i].add(letter)
+                    new_count[letter] += 1
                 case LetterResult.INCORRECT:
-                    new_exact.add(letter)
-                    new_min[letter] += 0  # Ensure letter is in min.
+                    self.incorrect[i].add(letter)
+                    self.exact.add(letter)
+                    new_count[letter] += 0  # Ensure letter is in dict
 
-        for letter, m in new_min.items():
-            self.min[letter] = max(m, self.min[letter])
-
-        self.exact |= new_exact
+        for letter, c in new_count.items():
+            self.count[letter] = max(c, self.count[letter])
 
     def matches(self, guess):
 
@@ -189,22 +194,22 @@ class Constraints():
 
         # All known correct letters in place.
         for i, letter in enumerate(guess):
+            # If we have a known letter, and don't match...
             if self.correct[i] and self.correct[i] != letter:
-                return False  # If it's incorrect, the word is incorrect.
+                return False
 
-            # Any MOVE letters in known wrong locations.
-            if letter in self.move:
-                if i in self.move[letter]:
-                    return False
+            # If we have a letter that's known to be incorrect in the current location...
+            if letter in self.incorrect[i]:
+                return False
 
             counts[letter] += 1
 
-        for letter, min in self.min.items():
+        for letter, c in self.count.items():
             if letter in self.exact:
-                if counts[letter] != min:
+                if counts[letter] != c:
                     return False
             else:
-                if counts[letter] < min:
+                if counts[letter] < c:
                     return False
 
         return True
@@ -217,6 +222,8 @@ def filter_dictionary(constraints, wordle_dictionary=dictionary()):
 if __name__ == '__main__':
     constraints = Constraints()
     constraints.update_graded('cares', [LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT])
+    constraints.update_graded('monty', [LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT])
+    constraints.update_graded('filii', [LetterResult.MOVE, LetterResult.MOVE, LetterResult.INCORRECT, LetterResult.INCORRECT, LetterResult.INCORRECT])
 
     valid_words = filter_dictionary(constraints)