Tweak coverage-html target

 - Don't try to rm -rf the directory before we start: somebody might
   have set it to ~, which would be quite sad.

 - Always quote the directory name

 - Use 'make reset-gcov' before running tests.

 - Use 'make check', not ./src/test/test

Makefile.am

@@ -76,11 +76,11 @@ reset-gcov:
 
 HTML_COVER_DIR=./coverage_html
 coverage-html: all
-	test -d $(HTML_COVER_DIR) && rm -rf $(HTML_COVER_DIR) || true
-	test -e `which lcov` || (echo "lcov must be installed. See <http://ltp.sourceforge.net/coverage/lcov.php>." && false)
-	mkdir -p $(HTML_COVER_DIR)
+	test -e "`which lcov`" || (echo "lcov must be installed. See <http://ltp.sourceforge.net/coverage/lcov.php>." && false)
+	test -d "$(HTML_COVER_DIR)" || mkdir -p "$(HTML_COVER_DIR)"
 	lcov --rc lcov_branch_coverage=1 --directory ./src --zerocounters
-	./src/test/test
+	$(MAKE) reset-gcov
+	$(MAKE) check
 	lcov --capture --rc lcov_branch_coverage=1 --no-external --directory . --output-file "$(HTML_COVER_DIR)/lcov.tmp"
 	lcov --remove "$(HTML_COVER_DIR)/lcov.tmp" --rc lcov_branch_coverage=1 'test/*' 'ext/tinytest*' '/usr/*' --output-file "$(HTML_COVER_DIR)/lcov.info"
 	genhtml --branch-coverage -o "$(HTML_COVER_DIR)" "$(HTML_COVER_DIR)/lcov.info"

changes/coverage-html

@@ -0,0 +1,5 @@
+  o Minor features (testing):
+
+    - Add a "coverage-html" make target to generate HTML-visualized
+      coverage results when building with --enable-coverage. (Requires lcov.)
+      Patch from Kevin Murray.