Move doc related modules to doc/requirements.txt

Change-Id: I995f7c4e0152a19d2ae2890d6940419f30638444

.gitignore

@@ -55,3 +55,5 @@ ChangeLog
 
 # reno build
 releasenotes/build
+releasenotes/notes/reno.cache
+RELEASENOTES.rst

doc/requirements.txt

@@ -0,0 +1,8 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
+openstackdocstheme>=1.18.1 # Apache-2.0
+sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7' # BSD
+sphinx!=1.6.6,!=1.6.7,>=1.6.2;python_version>='3.4' # BSD
+reno>=2.5.0 # Apache-2.0

test-requirements.txt

@@ -9,12 +9,7 @@ oslotest>=3.2.0 # Apache-2.0
 requests>=2.14.2 # Apache-2.0
 stestr>=2.0.0 # Apache-2.0
 
-# These are needed for docs generation/testing
-openstackdocstheme>=1.18.1 # Apache-2.0
-sphinx!=1.6.6,!=1.6.7,>=1.6.2,<2.0.0;python_version=='2.7' # BSD
-sphinx!=1.6.6,!=1.6.7,>=1.6.2;python_version>='3.4' # BSD
 doc8>=0.6.0 # Apache-2.0
-reno>=2.5.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 

tox.ini

@@ -10,6 +10,7 @@ setenv =
 install_command = pip install {opts} {packages}
 deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+  -r{toxinidir}/doc/requirements.txt
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
 whitelist_externals = find
@@ -30,7 +31,11 @@ commands = {posargs}
 
 [testenv:docs]
 basepython = python3
-commands = sphinx-build -W -b html doc/source doc/build/html {posargs}
+whitelist_externals =
+  rm
+commands =
+  rm -rf doc/build
+  sphinx-build -W -b html doc/source doc/build/html {posargs}
 
 [testenv:cover]
 basepython = python3