Change trys to checks (#28121)

Author: jbrockmendel

pandas/core/internals/blocks.py

@@ -2830,9 +2830,9 @@ def _replace_single(
  regex = regex_re or to_rep_re
 
  # try to get the pattern attribute (compiled re) or it's a string
- try:
+ if is_re(to_replace):
  pattern = to_replace.pattern
- except AttributeError:
+ else:
  pattern = to_replace
 
  # if the pattern is not empty and to_replace is either a string or a
@@ -2853,18 +2853,18 @@ def _replace_single(
  if isna(value) or not isinstance(value, str):
 
  def re_replacer(s):
- try:
+ if is_re(rx) and isinstance(s, str):
  return value if rx.search(s) is not None else s
- except TypeError:
+ else:
  return s
 
  else:
  # value is guaranteed to be a string here, s can be either a string
  # or null if it's null it gets returned
  def re_replacer(s):
- try:
+ if is_re(rx) and isinstance(s, str):
  return rx.sub(value, s)
- except TypeError:
+ else:
  return s
 
  f = np.vectorize(re_replacer, otypes=[self.dtype])