Partially revert "Refactor the sphinx-dev build environment to get rid of the link-stamp step"

This reverts commit 457c9f64.

This commit removed both the source copy step and the actual linking of the docs
sources. Turns out that the latter is "somewhat" necessary for a proper doc
build.

Close T2386

docs/Makefile

@@ -21,10 +21,14 @@ APIDOC_SWH_EXCLUDES = $(patsubst %,$(SWHPKGDIR)/%,$(APIDOC_EXCLUDES))
 
 html: sphinx/html
 
-sphinx/html: apidoc-stamp images-stamp rec-build-stamp
+sphinx/html: links-stamp apidoc-stamp images-stamp rec-build-stamp
+
+links-stamp:
+	bin/ln-sphinx-subprojects
+	touch $@
 
 apidoc: apidoc-stamp
-apidoc-stamp: images-stamp
+apidoc-stamp: links-stamp images-stamp
 	$(SPHINXAPIDOC) --implicit-namespaces $(APIDOC_OPTS) -o $(APIDOC_DIR) $(SWHPKGDIR) $(APIDOC_SWH_EXCLUDES)
 	touch $@
 
@@ -40,6 +44,7 @@ rec-build-stamp: $(wildcard ../../swh-*/docs/*.rst)
 	touch $@
 
 clean: sphinx/clean
+	bin/ln-sphinx-subprojects --remove
 	$(MAKE) -C images clean
 	rm -f *-stamp
 	rm -f $(APIDOC_DIR)/*

docs/bin/ln-sphinx-subprojects

+#!/bin/bash
+set -e
+
+create_links () {
+    mkdir -p sources
+    for pymodule in $(cd ../../ && bin/ls-py-modules) ; do
+        if [ "$pymodule" = 'swh-docs' ] ; then
+            continue
+        fi
+        if [ ! -e "$pymodule" -a -d "../../${pymodule}/docs" ] ; then
+            ln -s "../../${pymodule}/docs" "$pymodule"
+        fi
+    done
+}
+
+remove_links () {
+    for pymodule in $(cd ../../ && bin/ls-py-modules) ; do
+        if [ "$pymodule" = 'swh-docs' ] ; then
+            continue
+        fi
+        if [ -L "$pymodule" ] ; then
+            rm "$pymodule"
+        fi
+    done
+}
+
+if [ "$1" = "--remove" ] ; then
+    remove_links
+else
+    create_links
+fi

tox.ini

@@ -17,12 +17,12 @@ commands =
   {envpython} -m pifpaf run postgresql -- make -C docs {posargs:html}
 
 [testenv:sphinx-dev]
-setenv =
-  SWHPKGDIR = {envsitepackagesdir}/swh
 deps =
   django < 3
   -rrequirements-swh-dev.txt
   pifpaf
+setenv =
+  SWHPKGDIR = {envsitepackagesdir}/swh
 commands =
   {envpython} -m pifpaf run postgresql -- make -C docs {posargs:html}