Added the UPDATE_FAILED conditional to the visual comparison Makefiles.

When UPDATE_FAILED=true, failed tests will update the prototype PDFs
instead of terminating the procedure.

test/mu/compare-example/Makefile

@@ -18,7 +18,9 @@ all:
 	make -C $(EXAMPLEDIR) implode
 	$(FAKETIME) make -C $(EXAMPLEDIR) all
 	for PROTOTYPE in $(PROTOTYPES); do \
-		$(COMPARE) "$$PROTOTYPE" $(EXAMPLEDIR)/"$${PROTOTYPE##expected-}" || exit 1;\
+		$(COMPARE) "$$PROTOTYPE" $(EXAMPLEDIR)/"$${PROTOTYPE##expected-}" || \
+		{ [ "$(UPDATE_FAILED)" = true ] && \
+			mv $(EXAMPLEDIR)/"$${PROTOTYPE##expected-}" "$$PROTOTYPE"; } || exit 1; \
 	done
 	make -C $(EXAMPLEDIR) implode
 

test/mu/compare/Makefile

@@ -66,7 +66,8 @@ expected-%-lualatex.pdf: %.tex
 	@# The second run.
 	$(FAKETIME) pdflatex -jobname          $(basename $@) $<
 	@# Compare the result with the prototype.
-	! [ -e expected-$@ ] || $(COMPARE) expected-$@ $@
+	! [ -e expected-$@ ] || $(COMPARE) expected-$@ $@ || \
+	{ [ "$(UPDATE_FAILED)" = true ] && mv $@ expected-$@; }
 
 # This target typesets a LuaLaTeX test file and compares
 # it against a prototype.
@@ -83,7 +84,8 @@ expected-%-lualatex.pdf: %.tex
 	@# The second run.
 	$(FAKETIME) lualatex -jobname          $(basename $@) $<
 	@# Compare the result with the prototype.
-	! [ -e expected-$@ ] || $(COMPARE) expected-$@ $@
+	! [ -e expected-$@ ] || $(COMPARE) expected-$@ $@ || \
+	{ [ "$(UPDATE_FAILED)" = true ] && mv $@ expected-$@; }
 
 # This target removes any auxiliary files.
 clean: