UnicodeEncodeError: 'charmap' codec can't encode characters in position 6-19: character maps to <undefined>

[nmz787]

Describe the bug

Traceback (most recent call last):
  File "dflauncher.py", line 242, in <module>
    automate_script(3)
  File "dflauncher.py", line 167, in automate_script
    'Username:'], timeout=4)
  File "C:\Users\myusername\git\test\wexpect.py", line 1366, in expect
    return self.expect_list(compiled_pattern_list, timeout, searchwindowsize)
  File "C:\Users\myusername\git\test\wexpect.py", line 1380, in expect_list
    return self.expect_loop(searcher_re(pattern_list), timeout, searchwindowsize)
  File "C:\Users\myusername\git\test\wexpect.py", line 1433, in expect_loop
    c = self.read_nonblocking(self.maxread, timeout)
  File "C:\Users\myusername\git\test\wexpect.py", line 1793, in read_nonblocking
    self.logfile_read.write (s)
  File "C:\Python36\lib\encodings\cp1252.py", line 19, in encode
    return codecs.charmap_encode(input,self.errors,encoding_table)[0]
UnicodeEncodeError: 'charmap' codec can't encode characters in position 6-19: character maps to <undefined>

To Reproduce
I've got no clue... use a colon in the expectation?

Expected behavior
Not crash.

Environment:

• [windows version] 10
• [Python version] 3.6
• [wexpect version] latest from pypi source, v2.3.6

[raczben]

At the first sight it seems that the logging fails. Please try to remove the logging from the line 1793 as a workaround.

I will try to reproduce as soon as it is possible.

[raczben]

Here is a related StackOverflow post.

I have created a new branch: i11 for this issue.

unicode_parent can reproduce a very similar issue.

[nmz787]

I just encountered the error again.
For me it was self.logfile_read, not self.logfile... I applied what the stackoverflow post said, changing the wexpect.py line to:
self.logfile_read.write (s.encode("utf-8"))

and things seem to work now :)

[nmz787]

I had to update my local copy of wexpect.py with this line today, in place of the previous "fix":
self.logfile_read.write (s.encode("utf-8") if not isinstance(s, str) else s)
It was after using this line:

shell.logfile_read = sys.stdout

that I got the strange error:

Traceback (most recent call last):
  File "main.py", line 11, in <module>
    shell.expect(unique_prompt)
  File "C:\Users\nmz787\git\wexpect_issues\wexpect.py", line 1388, in expect
    return self.expect_list(compiled_pattern_list, timeout, searchwindowsize)
  File "C:\Users\nmz787\git\wexpect_issues\wexpect.py", line 1402, in expect_list
    return self.expect_loop(searcher_re(pattern_list), timeout, searchwindowsize)
  File "C:\Users\nmz787\git\wexpect_issues\wexpect.py", line 1455, in expect_loop
    c = self.read_nonblocking(self.maxread, timeout)
  File "C:\Users\nmz787\git\wexpect_issues\wexpect.py", line 1816, in read_nonblocking
    self.logfile_read.write (s.encode("utf-8") if isinstance(s, str) else s)
TypeError: write() argument must be str, not bytes

[raczben]

I beleive this is the same as #47