Replace typing-extensions Literal with the type of the Literal & run mypy, nosetest and sphinx in there own environment on cicd (#677)

* Improve tox.ini by running flake8, mypy, nosetests and sphinx in there own environment.

Improves isolation. Dependencies of one package won't influence the next.

This should fail for the current setup with typing-extensions.

* Try to fix actually running tox tests on travis

* Use recent tox

* Fix using Literal[False] for open_filename.

None has the same true value as False, and therefore it does not matter.

* Replace typing_extensions.Literal by the type of the literal

* Add line to CHANGELOG.md

.travis.yml

@@ -6,6 +6,6 @@ python:
   - "3.8"
   - "3.9"
 install:
-  - pip install tox==3.14.0 tox-travis flake8
+  - pip install tox tox-travis
 script:
   - tox -r

CHANGELOG.md

@@ -28,6 +28,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Support for Python 3.4 and 3.5 ([#522](https://github.com/pdfminer/pdfminer.six/pull/522))
 - Unused dependency on `sortedcontainers` package ([#525](https://github.com/pdfminer/pdfminer.six/pull/525))
 - Support for non-standard output streams that are not binary ([#523](https://github.com/pdfminer/pdfminer.six/pull/523))
+- Dependency on typing-extensions introduced by [#661](https://github.com/pdfminer/pdfminer.six/pull/661) ([#677](https://github.com/pdfminer/pdfminer.six/pull/677))
 
 ## [20201018]
 

pdfminer/utils.py

@@ -7,7 +7,6 @@ import struct
 from typing import (Any, BinaryIO, Callable, Dict, Generic, Iterable, Iterator,
                     List, Optional, Set, TextIO, Tuple, TypeVar, Union,
                     TYPE_CHECKING, cast)
-from typing_extensions import Literal
 from html import escape
 
 if TYPE_CHECKING:
@@ -55,10 +54,10 @@ class open_filename(object):
         exc_type: object,
         exc_val: object,
         exc_tb: object
-    ) -> Literal[False]:
+    ) -> None:
         if self.closing:
             self.file_handler.close()
-        return False
+        return
 
 
 def make_compat_bytes(in_str: str) -> bytes:

tools/pdf2txt.py

@@ -5,7 +5,6 @@ import argparse
 import logging
 import sys
 from typing import Any, Container, Iterable, List, Optional, Union
-from typing_extensions import Literal
 
 import pdfminer.high_level
 from pdfminer.layout import LAParams
@@ -18,7 +17,7 @@ OUTPUT_TYPES = ((".htm", "html"),
                 (".xml", "xml"),
                 (".tag", "tag"))
 
-FloatOrDisabled = Union[float, Literal["disabled"]]
+FloatOrDisabled = Union[float, str]  # Union[float, Literal["disabled"]]
 
 
 def float_or_disabled(x: str) -> FloatOrDisabled:

tox.ini

@@ -1,15 +1,33 @@
 [tox]
-envlist = py{36,37,38,3.9}
+envlist = py{36,37,38,39}-{nose,flake8,mypy,docs}
 
-[testenv]
+[testenv:py{36,37,38,39}-nose]
-extras =
+deps =
-    dev
+    nose
-    docs
+allowlist_externals =
-whitelist_externals =
+    nosetests
+commands =
+    nosetests --nologcapture
+
+[testenv:py{36,37,38,39}-flake8]
+deps =
+    flake8
+allowlist_externals =
     flake8
 commands =
     flake8 pdfminer/ tools/ tests/ --count --statistics
+
+[testenv:py{36,37,38,39}-mypy]
+deps =
+    mypy
+allowlist_externals =
+    mypy
+commands =
     mypy --install-types --non-interactive --show-error-codes .
-    nosetests --nologcapture
+
+[testenv:py{36,37,38,39}-docs]
+extras =
+    docs
+commands =
     python -m sphinx -b html docs/source docs/build/html
     python -m sphinx -b doctest docs/source docs/build/doctest