From 3666d14980c1059ebb25d57756bc04abef27b7d7 Mon Sep 17 00:00:00 2001
From: Stefan Schmidt <stefan@osg.samsung.com>
Date: Wed, 9 Mar 2016 23:02:46 +0100
Subject: [PATCH] build coverage: make coverage numbers more accurate by using
 a baseline

The lcov tool offers the functionality to have an initial run over the code base
before the tests are executed to make sure it catches all files, even the ones
that are not loaded during the test run.

This is something we missed so far. The reports have only been in relation to
the files that actually have been loaded during the test. We missed quite a
few files which made our numbers inaccurate. Things like
modules/emotion/gstreamer1 have no tests yet and thus never showed up in the
coverage report. While it has 103 functions and over thousand lines which need
to get covered. With the baseline this is handled now. Thanks goes to the folks
at LibreOffice who described their lcov setup here:
https://wiki.documentfoundation.org/Development/Lcov

New numbers are lower now as we count in all the files never loaded which
decreases our percentages.

Overall coverage rate:
  lines......: 30.2% (65119 of 215841 lines)
  functions..: 34.0% (6361 of 18733 functions)
  branches...: 23.6% (35627 of 151096 branches)
---
 Makefile.am | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index 9aecc454d4..8206b161b8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -428,13 +428,19 @@ lcov-reset:
 	@find $(top_builddir) -name "*.gcda" -delete
 	@lcov --zerocounters --directory $(top_builddir)
 
-lcov-report:
+lcov-baseline:
 	$(MKDIR_P) $(top_builddir)/coverage
-	lcov --capture --compat-libtool --no-external --output-file $(top_builddir)/coverage/coverage.info --directory $(top_builddir) --config-file .lcov-config --rc lcov_branch_coverage=1
-	lcov --remove $(top_builddir)/coverage/coverage.info '*.h' --output-file $(top_builddir)/coverage/coverage.cleaned.info --config-file .lcov-config --rc lcov_branch_coverage=1
-	lcov --remove $(top_builddir)/coverage/coverage.cleaned.info '*/tests/*' --output-file $(top_builddir)/coverage/coverage.cleaned2.info --config-file .lcov-config --rc lcov_branch_coverage=1
-	lcov --remove $(top_builddir)/coverage/coverage.cleaned2.info '*NONE*' --output-file $(top_builddir)/coverage/coverage.cleaned3.info --config-file .lcov-config --rc lcov_branch_coverage=1
-	genhtml --config-file .lcov-config --legend -t "$(PACKAGE_STRING)" -o $(top_builddir)/coverage/html $(top_builddir)/coverage/coverage.cleaned3.info
+	lcov --capture --initial --compat-libtool --no-external --output-file $(top_builddir)/coverage/coverage-baseline.info --directory $(top_builddir) --config-file .lcov-config --rc lcov_branch_coverage=1
+
+lcov-report:
+	lcov --capture --compat-libtool --no-external --output-file $(top_builddir)/coverage/coverage-check.info --directory $(top_builddir) --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --add-tracefile $(top_builddir)/coverage/coverage-baseline.info --add-tracefile $(top_builddir)/coverage/coverage-check.info --output-file $(top_builddir)/coverage/coverage.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --remove $(top_builddir)/coverage/coverage.info '*.h' --output-file $(top_builddir)/coverage/coverage.cleaned.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --remove $(top_builddir)/coverage/coverage.cleaned.info '*/tests/*' --output-file $(top_builddir)/coverage/coverage.cleaned2.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --remove $(top_builddir)/coverage/coverage.cleaned2.info '*NONE*' --output-file $(top_builddir)/coverage/coverage.cleaned3.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --remove $(top_builddir)/coverage/coverage.cleaned3.info '*/doc/*' --output-file $(top_builddir)/coverage/coverage.cleaned4.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	lcov --no-external --compat-libtool --remove $(top_builddir)/coverage/coverage.cleaned4.info '*usr/include*' --output-file $(top_builddir)/coverage/coverage.cleaned5.info --config-file .lcov-config --rc lcov_branch_coverage=1
+	genhtml --config-file .lcov-config --legend -t "$(PACKAGE_STRING)" -o $(top_builddir)/coverage/html $(top_builddir)/coverage/coverage.cleaned5.info
 	@echo "Coverage Report at $(top_builddir)/coverage/html"
 
 endif
@@ -444,6 +450,7 @@ if EFL_ENABLE_TESTS
 lcov-check:
 if EFL_ENABLE_COVERAGE
 	@$(MAKE) $(AM_MAKEFLAGS) lcov-reset
+	@$(MAKE) $(AM_MAKEFLAGS) lcov-baseline
 endif
 	@$(MAKE) $(AM_MAKEFLAGS) check
 if EFL_ENABLE_COVERAGE