Ignore false-positive github link errors (#146)

* Ignore false github link errors

* Remove tmp logfile

* Remove logfile

* Move cleanup to bash script

Makefile

@@ -65,9 +65,7 @@ linkcheck-all-subrepos-with-api: Makefile
 	@echo Step 3: Cloning all subrepositories again
 	./make_help_scripts/add_sub_repos
 	@echo Step 4: Check links
-	cp -r $(BUILDDIR)/html/doc/api/. doc/api/
-	make linkcheck
-	rm -rf doc/api/
+	./make_help_scripts/check_links $(BUILDDIR)
 
 multiversion: Makefile
 	@echo Building multi version documentation without API

make_help_scripts/check_links

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# This script is used to check the links in the ROS documentation.
+# due to a bug in the sphinx linkchecker, github anchors are false positives and
+# have to be explicitly ignored
+# https://github.com/sphinx-doc/sphinx/issues/9016
+
+LOGFILE="linkcheck.log"
+cleanup () {
+  rm "$LOGFILE"
+	rm -rf doc/api/
+}
+
+cp -r $1/html/doc/api/. doc/api/
+make linkcheck > "$LOGFILE"
+if grep broken "$LOGFILE" | grep -v -E 'github.*Anchor'; then
+    num_broken=$(grep broken "$LOGFILE" | grep -v -E 'github.*Anchor' | wc -l)
+    echo "Broken links found: $num_broken"
+    cleanup
+    exit 1
+fi
+cleanup
+exit 0