Added a way to display cell possible values

Author: nmacinnis

lib/sudoku.py

@@ -237,9 +237,10 @@ def brute_force(self, level=0):
                 )
                 _logger.error("Error was: %s", str(e))
                 _logger.error("Resulting table was: \n%s\n",
-                                str(new_table)
-                                )
-        _logger.info('%s solutions found at %s levels of recursion', len(solutions), level)
+                              str(new_table)
+                              )
+        _logger.info('%s solutions found at %s levels of recursion',
+                     len(solutions), level)
         if solutions:
             self.copy_from(solutions[0])
         return solutions
@@ -575,6 +576,17 @@ def section(self, section):
     def mates(self):
         return set(self.row.cells + self.column.cells + self.section.cells)
 
+    def display_potential_values(self):
+        values = [
+            (str(digit)
+             if (digit in self.potential_values or digit == self.value)
+             else ' ')
+            for digit in Sudoku.digits()
+        ]
+        return '\n'.join([
+            ''.join(row) for row in _split(values)
+        ])
+
 
 if __name__ == '__main__':
     cell = Cell()

test/test_sudoku.py

@@ -22,7 +22,7 @@ def _string_to_table(st):
             else:
                 raise Exception("wasn't sure what to do with %s" % character)
             _logger.info('Setting (%s, %s) to %s based on provided table',
-                            i, j, character)
+                         i, j, character)
             if value is not None:
                 try:
                     table.set(i, j, value)
@@ -518,6 +518,34 @@ def test_cell_clear_potential_value(self):
             cell.clear_potential_value(i)
         assert cell.potential_values == [9]
 
+    def test_display_potential_values_default(self):
+        cell = Cell()
+        result = cell.display_potential_values()
+        self.assertEquals('123\n'
+                          '456\n'
+                          '789', result)
+        _logger.info('\n%s\n', result)
+
+    def test_display_potential_values_partial(self):
+        cell = Cell()
+        cell.clear_potential_value(1)
+        cell.clear_potential_value(5)
+        cell.clear_potential_value(9)
+        result = cell.display_potential_values()
+        self.assertEquals(' 23\n'
+                          '4 6\n'
+                          '78 ', result)
+        _logger.info('\n%s\n', result)
+
+    def test_display_potential_values_full(self):
+        cell = Cell()
+        cell.value = 5
+        result = cell.display_potential_values()
+        self.assertEquals('   \n'
+                          ' 5 \n'
+                          '   ', result)
+        _logger.info('\n%s\n', result)
+
 
 class TestRow(unittest.TestCase):
     def test_str(self):