From 92862e28ec3f3cd0701f07bc047acab1e8643490 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Wed, 14 Apr 2021 20:19:26 +0200
Subject: [PATCH] Enable parallelism in Sphinx

---
 docs/pip_sphinxext.py | 8 ++++++--
 tox.ini               | 4 ++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/docs/pip_sphinxext.py b/docs/pip_sphinxext.py
index 8e4385a33..12e098fc0 100644
--- a/docs/pip_sphinxext.py
+++ b/docs/pip_sphinxext.py
@@ -5,7 +5,7 @@ import pathlib
 import re
 import sys
 from textwrap import dedent
-from typing import Iterable, Iterator, List, Optional
+from typing import Dict, Iterable, Iterator, List, Optional, Union
 
 from docutils import nodes, statemachine
 from docutils.parsers import rst
@@ -293,7 +293,7 @@ class PipCLIDirective(rst.Directive):
         return [node]
 
 
-def setup(app: Sphinx) -> None:
+def setup(app: Sphinx) -> Dict[str, Union[bool, str]]:
     app.add_directive("pip-command-usage", PipCommandUsage)
     app.add_directive("pip-command-description", PipCommandDescription)
     app.add_directive("pip-command-options", PipCommandOptions)
@@ -304,3 +304,7 @@ def setup(app: Sphinx) -> None:
     )
     app.add_directive("pip-news-include", PipNewsInclude)
     app.add_directive("pip-cli", PipCLIDirective)
+    return {
+        "parallel_read_safe": True,
+        "parallel_write_safe": True,
+    }
diff --git a/tox.ini b/tox.ini
index 0b9511bf9..60f133cea 100644
--- a/tox.ini
+++ b/tox.ini
@@ -51,12 +51,12 @@ setenv =
 deps = -r{toxinidir}/tools/requirements/docs.txt
 basepython = python3
 commands =
-    sphinx-build -W -d {envtmpdir}/doctrees/html -b html docs/html docs/build/html
+    sphinx-build -W -j auto -d {envtmpdir}/doctrees/html -b html docs/html docs/build/html
     # Having the conf.py in the docs/html is weird but needed because we
     # can not use a different configuration directory vs source directory on RTD
     # currently -- https://github.com/rtfd/readthedocs.org/issues/1543.
     # That is why we have a "-c docs/html" in the next line.
-    sphinx-build -W -d {envtmpdir}/doctrees/man -b man docs/man docs/build/man -c docs/html
+    sphinx-build -W -j auto -d {envtmpdir}/doctrees/man -b man docs/man docs/build/man -c docs/html
 
 [testenv:lint]
 skip_install = True