Specifying Sphinx version before 5 because the manual layout is curre…

…ntly broken under Sphinx 5 and 6 <#121>.  Because that means we're using a variant of Sphinx, also making a venv-installed Sphinx the default.

manual/Makefile

@@ -3,7 +3,7 @@
 
 # You can set these variables from the command line.
 SPHINXOPTS    =
-SPHINXBUILD   = sphinx-build
+SPHINXBUILD   = tool/bin/sphinx-build
 PAPER         =
 BUILDDIR      = .
 
@@ -43,38 +43,38 @@ clean:
 	-rm -rf $(BUILDDIR)/{changes,devhelp,dirhtml,doctest,doctrees,epub,html,htmlhelp,json,latex,linkcheck,locale,man,pickle,qthelp,singlehtml,texinfo,text}
 	-find $(BUILDDIR)/source/design -name '*.rst' ! -name 'index.rst' ! -name 'old.rst' -exec rm -f '{}' ';'
 
-html:
+html: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
 
-dirhtml:
+dirhtml: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
 
-singlehtml:
+singlehtml: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
 	@echo
 	@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
 
-pickle:
+pickle: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
 	@echo
 	@echo "Build finished; now you can process the pickle files."
 
-json:
+json: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
 	@echo
 	@echo "Build finished; now you can process the JSON files."
 
-htmlhelp:
+htmlhelp: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
 	@echo
 	@echo "Build finished; now you can run HTML Help Workshop with the" \
 	      ".hhp project file in $(BUILDDIR)/htmlhelp."
 
-qthelp:
+qthelp: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
 	@echo
 	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
@@ -83,7 +83,7 @@ qthelp:
 	@echo "To view the help file:"
 	@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/MemoryPoolSystem.qhc"
 
-devhelp:
+devhelp: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
 	@echo
 	@echo "Build finished."
@@ -92,74 +92,74 @@ devhelp:
 	@echo "# ln -s $(BUILDDIR)/devhelp $$HOME/.local/share/devhelp/MemoryPoolSystem"
 	@echo "# devhelp"
 
-epub:
+epub: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
 	@echo
 	@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
 
-latex:
+latex: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo
 	@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
 	@echo "Run \`make' in that directory to run these through (pdf)latex" \
 	      "(use \`make latexpdf' here to do that automatically)."
 
-latexpdf:
+latexpdf: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo "Running LaTeX files through pdflatex..."
 	$(MAKE) -C $(BUILDDIR)/latex all-pdf
 	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
 
-text:
+text: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
 	@echo
 	@echo "Build finished. The text files are in $(BUILDDIR)/text."
 
-man:
+man: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
 	@echo
 	@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
 
-texinfo:
+texinfo: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo
 	@echo "Build finished. The Texinfo files are in $(BUILDDIR)/texinfo."
 	@echo "Run \`make' in that directory to run these through makeinfo" \
 	      "(use \`make info' here to do that automatically)."
 
-info:
+info: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo "Running Texinfo files through makeinfo..."
 	make -C $(BUILDDIR)/texinfo info
 	@echo "makeinfo finished; the Info files are in $(BUILDDIR)/texinfo."
 
-gettext:
+gettext: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b gettext $(I18NSPHINXOPTS) $(BUILDDIR)/locale
 	@echo
 	@echo "Build finished. The message catalogs are in $(BUILDDIR)/locale."
 
-changes:
+changes: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
 	@echo
 	@echo "The overview file is in $(BUILDDIR)/changes."
 
-linkcheck:
+linkcheck: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck
 	@echo
 	@echo "Link check complete; look for any errors in the above output " \
 	      "or in $(BUILDDIR)/linkcheck/output.txt."
 
-doctest:
+doctest: $(SPHINXBUILD)
 	$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
 	@echo "Testing of doctests in the sources finished, look at the " \
 	      "results in $(BUILDDIR)/doctest/output.txt."
 
 tools: tool/bin/sphinx-build
 
 tool/bin/sphinx-build: tool/bin/pip
-	tool/bin/pip install sphinx
+	tool/bin/pip install 'sphinx < 5' # Layout breaks in Sphinx >= 5.  See <https://github.com/Ravenbrook/mps/issues/121>.
 	@echo "You can now use \`make SPHINXBUILD=tool/bin/sphinx-build html' etc."
 	@echo "Or add tool/bin to your path."
 
 tool/bin/pip:
-	virtualenv tool
+	python3 -mvenv tool