fix: codec error message (#902)

Signed-off-by: 117503445 <[email protected]>
Co-authored-by: Pieter Marsman <[email protected]>

CHANGELOG.md

@@ -9,6 +9,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - Resolving mediabox and pdffont ([#834](https://github.com/pdfminer/pdfminer.six/pull/834))
 - Keywords that aren't terminated by the pattern `END_KEYWORD` before end-of-stream are parsed ([#885](https://github.com/pdfminer/pdfminer.six/pull/885))
+- `ValueError` wrong error message when specifying codec for text output  ([#902](https://github.com/pdfminer/pdfminer.six/pull/902))
 
 ## [20231228]
 

pdfminer/converter.py

@@ -409,8 +409,10 @@ def __init__(
         )
 
         # write() assumes a codec for binary I/O, or no codec for text I/O.
-        if self.outfp_binary == (not self.codec):
+        if self.outfp_binary and not self.codec:
             raise ValueError("Codec is required for a binary I/O output")
+        if not self.outfp_binary and self.codec:
+            raise ValueError("Codec must not be specified for a text I/O output")
 
         if text_colors is None:
             text_colors = {"char": "black"}