ci: rename the library of common functions

The name is hard-coded to reflect that we use Travis CI for continuous
testing.

In the next commits, we will extend this to be able use Azure DevOps,
too.

So let's adjust the name to make it more generic.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 132 insertions, 0 deletions

diff --git a/ci/lib.sh b/ci/lib.sh
new file mode 100755
index 0000000000..9c6ddeb374
--- /dev/null
+++ b/ci/lib.sh
@@ -0,0 +1,132 @@
+# Library of functions shared by all CI scripts
+
+skip_branch_tip_with_tag () {
+	# Sometimes, a branch is pushed at the same time the tag that points
+	# at the same commit as the tip of the branch is pushed, and building
+	# both at the same time is a waste.
+	#
+	# When the build is triggered by a push to a tag, $CI_BRANCH will
+	# have that tagname, e.g. v2.14.0.  Let's see if $CI_BRANCH is
+	# exactly at a tag, and if so, if it is different from $CI_BRANCH.
+	# That way, we can tell if we are building the tip of a branch that
+	# is tagged and we can skip the build because we won't be skipping a
+	# build of a tag.
+
+	if TAG=$(git describe --exact-match "$CI_BRANCH" 2>/dev/null) &&
+		test "$TAG" != "$CI_BRANCH"
+	then
+		echo "$(tput setaf 2)Tip of $CI_BRANCH is exactly at $TAG$(tput sgr0)"
+		exit 0
+	fi
+}
+
+# Save some info about the current commit's tree, so we can skip the build
+# job if we encounter the same tree again and can provide a useful info
+# message.
+save_good_tree () {
+	echo "$(git rev-parse $TRAVIS_COMMIT^{tree}) $TRAVIS_COMMIT $TRAVIS_JOB_NUMBER $TRAVIS_JOB_ID" >>"$good_trees_file"
+	# limit the file size
+	tail -1000 "$good_trees_file" >"$good_trees_file".tmp
+	mv "$good_trees_file".tmp "$good_trees_file"
+}
+
+# Skip the build job if the same tree has already been built and tested
+# successfully before (e.g. because the branch got rebased, changing only
+# the commit messages).
+skip_good_tree () {
+	if ! good_tree_info="$(grep "^$(git rev-parse $TRAVIS_COMMIT^{tree}) " "$good_trees_file")"
+	then
+		# Haven't seen this tree yet, or no cached good trees file yet.
+		# Continue the build job.
+		return
+	fi
+
+	echo "$good_tree_info" | {
+		read tree prev_good_commit prev_good_job_number prev_good_job_id
+
+		if test "$TRAVIS_JOB_ID" = "$prev_good_job_id"
+		then
+			cat <<-EOF
+			$(tput setaf 2)Skipping build job for commit $TRAVIS_COMMIT.$(tput sgr0)
+			This commit has already been built and tested successfully by this build job.
+			To force a re-build delete the branch's cache and then hit 'Restart job'.
+			EOF
+		else
+			cat <<-EOF
+			$(tput setaf 2)Skipping build job for commit $TRAVIS_COMMIT.$(tput sgr0)
+			This commit's tree has already been built and tested successfully in build job $prev_good_job_number for commit $prev_good_commit.
+			The log of that build job is available at https://travis-ci.org/$TRAVIS_REPO_SLUG/jobs/$prev_good_job_id
+			To force a re-build delete the branch's cache and then hit 'Restart job'.
+			EOF
+		fi
+	}
+
+	exit 0
+}
+
+check_unignored_build_artifacts ()
+{
+	! git ls-files --other --exclude-standard --error-unmatch \
+		-- ':/*' 2>/dev/null ||
+	{
+		echo "$(tput setaf 1)error: found unignored build artifacts$(tput sgr0)"
+		false
+	}
+}
+
+# Set 'exit on error' for all CI scripts to let the caller know that
+# something went wrong.
+# Set tracing executed commands, primarily setting environment variables
+# and installing dependencies.
+set -ex
+
+# When building a PR, TRAVIS_BRANCH refers to the *target* branch. Not what we
+# want here. We want the source branch instead.
+CI_BRANCH="${TRAVIS_PULL_REQUEST_BRANCH:-$TRAVIS_BRANCH}"
+
+cache_dir="$HOME/travis-cache"
+good_trees_file="$cache_dir/good-trees"
+
+mkdir -p "$cache_dir"
+
+skip_branch_tip_with_tag
+skip_good_tree
+
+if test -z "$jobname"
+then
+	jobname="$TRAVIS_OS_NAME-$CC"
+fi
+
+export DEVELOPER=1
+export DEFAULT_TEST_TARGET=prove
+export GIT_PROVE_OPTS="--timer --jobs 3 --state=failed,slow,save"
+export GIT_TEST_OPTS="--verbose-log -x --immediate"
+export GIT_TEST_CLONE_2GB=YesPlease
+if [ "$jobname" = linux-gcc ]; then
+	export CC=gcc-8
+fi
+
+case "$jobname" in
+linux-clang|linux-gcc)
+	export GIT_TEST_HTTPD=YesPlease
+
+	# The Linux build installs the defined dependency versions below.
+	# The OS X build installs the latest available versions. Keep that
+	# in mind when you encounter a broken OS X build!
+	export LINUX_P4_VERSION="16.2"
+	export LINUX_GIT_LFS_VERSION="1.5.2"
+
+	P4_PATH="$HOME/custom/p4"
+	GIT_LFS_PATH="$HOME/custom/git-lfs"
+	export PATH="$GIT_LFS_PATH:$P4_PATH:$PATH"
+	;;
+osx-clang|osx-gcc)
+	# t9810 occasionally fails on Travis CI OS X
+	# t9816 occasionally fails with "TAP out of sequence errors" on
+	# Travis CI OS X
+	export GIT_SKIP_TESTS="t9810 t9816"
+	;;
+GIT_TEST_GETTEXT_POISON)
+	export GIT_TEST_GETTEXT_POISON=YesPlease
+	;;
+esac