BUG:fix replacer's dtype is not respected (pandas-dev#26632)

Author: peterpanmj

pandas/core/internals/blocks.py

@@ -2914,6 +2914,8 @@ def _replace_coerce(
             if convert:
                 block = [b.convert(numeric=False, copy=True) for b in block]
             return block
+        if convert:
+            return [self.convert(numeric=False, copy=True)]
         return self
 
 

pandas/core/internals/managers.py

@@ -632,7 +632,7 @@ def comp(s, regex=False):
                         convert=convert,
                         regex=regex,
                     )
-                    if m.any():
+                    if m.any() or convert:
                         new_rb = _extend_blocks(result, new_rb)
                     else:
                         new_rb.append(b)