Merge branch 'master' into fix-issue24255

* master: (104 commits)
  Fast path for exact floats in math.hypot() and math.dist() (GH-8949)
  Remove AIX workaround test_subprocess (GH-8939)
  bpo-34503: Fix refleak in PyErr_SetObject() (GH-8934)
  closes bpo-34504: Remove the useless NULL check in PySequence_Check(). (GH-8935)
  closes bpo-34501: PyType_FromSpecWithBases: Check spec->name before dereferencing it. (GH-8930)
  closes bpo-34502: Remove a note about utf8_mode from sys.exit() docs. (GH-8928)
  Remove unneeded PyErr_Clear() in _winapi_SetNamedPipeHandleState_impl() (GH-8281)
  Fix markup in stdtypes documentation (GH-8905)
  bpo-34395: Don't free allocated memory on realloc fail in load_mark() in _pickle.c. (GH-8788)
  Fix upsizing of marks stack in pickle module. (GH-8860)
  bpo-34171: Prevent creating Lib/trace.cover when run the trace module. (GH-8841)
  closes bpo-34493: Objects/genobject.c: Add missing NULL check to compute_cr_origin() (GH-8911)
  Fixed typo with asynccontextmanager code example (GH-8845)
  bpo-34426: fix typo (__lltrace__ -> __ltrace__) (GH-8822)
  bpo-13312: Avoid int underflow in time year. (GH-8912)
  bpo-34492: Python/coreconfig.c: Fix _Py_wstrlist_copy() (GH-8910)
  bpo-34448: Improve output of usable wchar_t check (GH-8846)
  closes bpo-34471: _datetime: Add missing NULL check to tzinfo_from_isoformat_results. (GH-8869)
  bpo-6700: Fix inspect.getsourcelines for module level frames/tracebacks (GH-8864)
  Fix typo in the dataclasses's doc (GH-8896)
  ...

Author: CuriousLearner

.vsts/docs.yml

@@ -23,21 +23,35 @@ steps:
   clean: true
   fetchDepth: 5
 
+- script: |
+   git fetch -q origin $(system.pullRequest.targetBranch)
+   if ! git diff --name-only HEAD $(git merge-base HEAD FETCH_HEAD) | grep -qE '(\.rst$|^Doc|^Misc)'
+   then
+     echo "No docs were updated, stopping build process."
+     echo "##vso[task.setvariable variable=NoDocs]true"
+     exit
+   fi
+  displayName: Detect doc-only changes
+  condition: and(succeeded(), variables['system.pullRequest.targetBranch'])
+
 - task: UsePythonVersion@0
   displayName: 'Use Python 3.6 or later'
   inputs:
     versionSpec: '>=3.6'
+  condition: and(succeeded(), ne(variables['NoDocs'], 'true'))
 
 - script: python -m pip install sphinx~=1.6.1 blurb python-docs-theme
   displayName: 'Install build dependencies'
+  condition: and(succeeded(), ne(variables['NoDocs'], 'true'))
 
 - script: make check suspicious html PYTHON=python
   workingDirectory: '$(build.sourcesDirectory)/Doc'
   displayName: 'Build documentation'
+  condition: and(succeeded(), ne(variables['NoDocs'], 'true'))
 
 - task: PublishBuildArtifacts@1
   displayName: 'Publish build'
-  condition: and(succeeded(), ne(variables['Build.Reason'], 'PullRequest'))
+  condition: and(and(succeeded(), ne(variables['Build.Reason'], 'PullRequest')), ne(variables['NoDocs'], 'true'))
   inputs:
     PathToPublish: '$(build.sourcesDirectory)/Doc/build'
     ArtifactName: build

.vsts/linux-coverage.yml

@@ -27,12 +27,24 @@ steps:
   clean: true
   fetchDepth: 5
 
+- script: |
+   git fetch -q origin $(system.pullRequest.targetBranch)
+   if ! git diff --name-only HEAD $(git merge-base HEAD FETCH_HEAD) | grep -qvE '(\.rst$|^Doc|^Misc)'
+   then
+     echo "Only docs were updated, stopping build process."
+     echo "##vso[task.setvariable variable=DocOnly]true"
+     exit
+   fi
+  displayName: Detect doc-only changes
+  condition: and(succeeded(), variables['system.pullRequest.targetBranch'])
+
 #- template: linux-deps.yml
 
 # See https://github.com/Microsoft/vsts-agent/blob/master/docs/preview/yamlgettingstarted-templates.md
 # For now, we copy/paste the steps
 - script: echo "deb-src http://archive.ubuntu.com/ubuntu/ xenial main" > /etc/apt/sources.list.d/python.list && sudo apt-get update
   displayName: 'Update apt-get lists'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: echo ##vso[task.prependpath]$(OPENSSL_DIR)
   displayName: 'Add $(OPENSSL_DIR) to PATH'
@@ -55,24 +67,32 @@ steps:
     uuid-dev
     xvfb
   displayName: 'Install dependencies'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 - script: python3 Tools/ssl/multissltests.py --steps=library --base-directory $(build.sourcesDirectory)/multissl --openssl $(OPENSSL) --system Linux
   displayName: 'python multissltests.py'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 
 - script: ./configure --with-pydebug
   displayName: 'Configure CPython (debug)'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make -s -j4
   displayName: 'Build CPython'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: ./python -m venv venv && ./venv/bin/python -m pip install -U coverage
   displayName: 'Set up virtual environment'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: ./venv/bin/python -m test.pythoninfo
   displayName: 'Display build info'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: xvfb-run ./venv/bin/python -m coverage run --pylib -m test --fail-env-changed -uall,-cpu -x test_multiprocessing_fork -x test_multiprocessing_forkserver -x test_multiprocessing_spawn -x test_concurrent_futures
   displayName: 'Tests with coverage'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: source ./venv/bin/activate && bash <(curl -s https://codecov.io/bash)
   displayName: 'Publish code coverage results'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))

.vsts/linux-pr.yml

@@ -27,15 +27,29 @@ steps:
   clean: true
   fetchDepth: 5
 
+- script: |
+   git fetch -q origin $(system.pullRequest.targetBranch)
+   if ! git diff --name-only HEAD $(git merge-base HEAD FETCH_HEAD) | grep -qvE '(\.rst$|^Doc|^Misc)'
+   then
+     echo "Only docs were updated, stopping build process."
+     echo "##vso[task.setvariable variable=DocOnly]true"
+     exit
+   fi
+  displayName: Detect doc-only changes
+  condition: and(succeeded(), variables['system.pullRequest.targetBranch'])
+
 #- template: linux-deps.yml
 
 # See https://github.com/Microsoft/vsts-agent/blob/master/docs/preview/yamlgettingstarted-templates.md
 # For now, we copy/paste the steps
 - script: echo "deb-src http://archive.ubuntu.com/ubuntu/ xenial main" > /etc/apt/sources.list.d/python.list && sudo apt-get update
   displayName: 'Update apt-get lists'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: echo ##vso[task.prependpath]$(OPENSSL_DIR)
   displayName: 'Add $(OPENSSL_DIR) to PATH'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
+
 - script: >
     sudo apt-get -yq install
     build-essential
@@ -55,22 +69,30 @@ steps:
     uuid-dev
     xvfb
   displayName: 'Install dependencies'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
+
 - script: python3 Tools/ssl/multissltests.py --steps=library --base-directory $(build.sourcesDirectory)/multissl --openssl $(OPENSSL) --system Linux
   displayName: 'python multissltests.py'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 
 - script: ./configure --with-pydebug
   displayName: 'Configure CPython (debug)'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make -s -j4
   displayName: 'Build CPython'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make pythoninfo
   displayName: 'Display build info'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 # Run patchcheck and fail if anything is discovered
 - script: ./python Tools/scripts/patchcheck.py --travis true
   displayName: 'Run patchcheck.py'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: xvfb-run make buildbottest TESTOPTS="-j4 -uall,-cpu"
   displayName: 'Tests'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))

.vsts/macos-pr.yml

@@ -24,14 +24,32 @@ steps:
   clean: true
   fetchDepth: 5
 
+- script: |
+   git fetch -q origin $(system.pullRequest.targetBranch)
+   changes = $(git diff --name-only HEAD $(git merge-base HEAD FETCH_HEAD))
+   echo "Files changed:"
+   echo "$changes"
+   if ! echo "$changes" | grep -qvE '(\.rst$)|(^Doc)|(^Misc)'
+   then
+     echo "Only docs were updated, stopping build process."
+     echo "##vso[task.setvariable variable=DocOnly]true"
+     exit
+   fi
+  displayName: Detect doc-only changes
+  condition: and(succeeded(), variables['system.pullRequest.targetBranch'])
+
 - script: ./configure --with-pydebug --with-openssl=/usr/local/opt/openssl --prefix=/opt/python-vsts
   displayName: 'Configure CPython (debug)'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make -s -j4
   displayName: 'Build CPython'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make pythoninfo
   displayName: 'Display build info'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: make buildbottest TESTOPTS="-j4 -uall,-cpu"
   displayName: 'Tests'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))

.vsts/windows-pr.yml

@@ -37,13 +37,25 @@ steps:
   clean: true
   fetchDepth: 5
 
+- powershell: |
+   git fetch -q origin $(System.PullRequest.TargetBranch)
+   if (-not (git diff --name-only HEAD (git merge-base HEAD FETCH_HEAD) | sls -NotMatch '(\.rst$)|(^Doc)|(^Misc)')) {
+      Write-Host 'Only docs were updated. Skipping build'
+      Write-Host '##vso[task.setvariable variable=DocOnly]true'
+   }
+  displayName: Detect doc-only changes
+  condition: and(succeeded(), variables['System.PullRequest.TargetBranch'])
+
 - script: PCbuild\build.bat -e $(buildOpt)
   displayName: 'Build CPython'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: python.bat -m test.pythoninfo
   displayName: 'Display build info'
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))
 
 - script: PCbuild\rt.bat -q -uall -u-cpu -rwW --slowest --timeout=1200 -j0
   displayName: 'Tests'
   env:
     PREFIX: $(Py_OutDir)\$(outDirSuffix)
+  condition: and(succeeded(), ne(variables['DocOnly'], 'true'))

Doc/README.rst

@@ -33,7 +33,7 @@ To get started on UNIX, you can create a virtual environment with the command ::
   make venv
 
 That will install all the tools necessary to build the documentation. Assuming
-the virtual environment was created in the ``env`` directory (the default;
+the virtual environment was created in the ``venv`` directory (the default;
 configurable with the VENVDIR variable), you can run the following command to
 build the HTML output files::
 

Doc/glossary.rst

@@ -123,10 +123,10 @@ Glossary
       :meth:`__aiter__` method.  Introduced by :pep:`492`.
 
    asynchronous iterator
-      An object that implements :meth:`__aiter__` and :meth:`__anext__`
+      An object that implements the :meth:`__aiter__` and :meth:`__anext__`
       methods.  ``__anext__`` must return an :term:`awaitable` object.
-      :keyword:`async for` resolves awaitable returned from asynchronous
-      iterator's :meth:`__anext__` method until it raises
+      :keyword:`async for` resolves the awaitables returned by an asynchronous
+      iterator's :meth:`__anext__` method until it raises a
       :exc:`StopAsyncIteration` exception.  Introduced by :pep:`492`.
 
    attribute

Doc/howto/functional.rst

@@ -198,7 +198,7 @@ for it.
 
 You can experiment with the iteration interface manually:
 
-    >>> L = [1,2,3]
+    >>> L = [1, 2, 3]
     >>> it = iter(L)
     >>> it  #doctest: +ELLIPSIS
     <...iterator object at ...>
@@ -229,7 +229,7 @@ iterator.  These two statements are equivalent::
 Iterators can be materialized as lists or tuples by using the :func:`list` or
 :func:`tuple` constructor functions:
 
-    >>> L = [1,2,3]
+    >>> L = [1, 2, 3]
     >>> iterator = iter(L)
     >>> t = tuple(iterator)
     >>> t
@@ -238,10 +238,10 @@ Iterators can be materialized as lists or tuples by using the :func:`list` or
 Sequence unpacking also supports iterators: if you know an iterator will return
 N elements, you can unpack them into an N-tuple:
 
-    >>> L = [1,2,3]
+    >>> L = [1, 2, 3]
     >>> iterator = iter(L)
-    >>> a,b,c = iterator
-    >>> a,b,c
+    >>> a, b, c = iterator
+    >>> a, b, c
     (1, 2, 3)
 
 Built-in functions such as :func:`max` and :func:`min` can take a single
@@ -411,7 +411,7 @@ lengths of all the sequences.  If you have two lists of length 3, the output
 list is 9 elements long:
 
     >>> seq1 = 'abc'
-    >>> seq2 = (1,2,3)
+    >>> seq2 = (1, 2, 3)
     >>> [(x, y) for x in seq1 for y in seq2]  #doctest: +NORMALIZE_WHITESPACE
     [('a', 1), ('a', 2), ('a', 3),
      ('b', 1), ('b', 2), ('b', 3),
@@ -479,7 +479,7 @@ Here's a sample usage of the ``generate_ints()`` generator:
       File "stdin", line 2, in generate_ints
     StopIteration
 
-You could equally write ``for i in generate_ints(5)``, or ``a,b,c =
+You could equally write ``for i in generate_ints(5)``, or ``a, b, c =
 generate_ints(3)``.
 
 Inside a generator function, ``return value`` causes ``StopIteration(value)``
@@ -695,17 +695,17 @@ truth values of an iterable's contents.  :func:`any` returns ``True`` if any ele
 in the iterable is a true value, and :func:`all` returns ``True`` if all of the
 elements are true values:
 
-    >>> any([0,1,0])
+    >>> any([0, 1, 0])
     True
-    >>> any([0,0,0])
+    >>> any([0, 0, 0])
     False
-    >>> any([1,1,1])
+    >>> any([1, 1, 1])
     True
-    >>> all([0,1,0])
+    >>> all([0, 1, 0])
     False
-    >>> all([0,0,0])
+    >>> all([0, 0, 0])
     False
-    >>> all([1,1,1])
+    >>> all([1, 1, 1])
     True
 
 
@@ -764,7 +764,7 @@ which defaults to 0, and the interval between numbers, which defaults to 1::
 a provided iterable and returns a new iterator that returns its elements from
 first to last.  The new iterator will repeat these elements infinitely. ::
 
-    itertools.cycle([1,2,3,4,5]) =>
+    itertools.cycle([1, 2, 3, 4, 5]) =>
       1, 2, 3, 4, 5, 1, 2, 3, 4, 5, ...
 
 :func:`itertools.repeat(elem, [n]) <itertools.repeat>` returns the provided
@@ -875,7 +875,7 @@ iterable's results. ::
 iterators and returns only those elements of *data* for which the corresponding
 element of *selectors* is true, stopping whenever either one is exhausted::
 
-    itertools.compress([1,2,3,4,5], [True, True, False, False, True]) =>
+    itertools.compress([1, 2, 3, 4, 5], [True, True, False, False, True]) =>
        1, 2, 5
 
 
@@ -1035,7 +1035,7 @@ first calculation. ::
     Traceback (most recent call last):
       ...
     TypeError: reduce() of empty sequence with no initial value
-    >>> functools.reduce(operator.mul, [1,2,3], 1)
+    >>> functools.reduce(operator.mul, [1, 2, 3], 1)
     6
     >>> functools.reduce(operator.mul, [], 1)
     1
@@ -1045,9 +1045,9 @@ elements of the iterable.  This case is so common that there's a special
 built-in called :func:`sum` to compute it:
 
     >>> import functools, operator
-    >>> functools.reduce(operator.add, [1,2,3,4], 0)
+    >>> functools.reduce(operator.add, [1, 2, 3, 4], 0)
     10
-    >>> sum([1,2,3,4])
+    >>> sum([1, 2, 3, 4])
     10
     >>> sum([])
     0
@@ -1057,22 +1057,22 @@ write the obvious :keyword:`for` loop::
 
    import functools
    # Instead of:
-   product = functools.reduce(operator.mul, [1,2,3], 1)
+   product = functools.reduce(operator.mul, [1, 2, 3], 1)
 
    # You can write:
    product = 1
-   for i in [1,2,3]:
+   for i in [1, 2, 3]:
        product *= i
 
 A related function is :func:`itertools.accumulate(iterable, func=operator.add)
 <itertools.accumulate>`.  It performs the same calculation, but instead of
 returning only the final result, :func:`accumulate` returns an iterator that
 also yields each partial result::
 
-    itertools.accumulate([1,2,3,4,5]) =>
+    itertools.accumulate([1, 2, 3, 4, 5]) =>
       1, 3, 6, 10, 15
 
-    itertools.accumulate([1,2,3,4,5], operator.mul) =>
+    itertools.accumulate([1, 2, 3, 4, 5], operator.mul) =>
       1, 2, 6, 24, 120
 
 
@@ -1156,7 +1156,7 @@ But it would be best of all if I had simply used a ``for`` loop::
 
 Or the :func:`sum` built-in and a generator expression::
 
-     total = sum(b for a,b in items)
+     total = sum(b for a, b in items)
 
 Many uses of :func:`functools.reduce` are clearer when written as ``for`` loops.
 

Doc/howto/logging.rst

@@ -750,9 +750,9 @@ the new dictionary-based approach:
         level: DEBUG
         handlers: [console]
         propagate: no
-    root:
-      level: DEBUG
-      handlers: [console]
+      root:
+        level: DEBUG
+        handlers: [console]
 
 For more information about logging using a dictionary, see
 :ref:`logging-config-api`.