1 files changed, 104 insertions, 3 deletions
diff --git a/ci/lib-travisci.sh b/ci/lib-travisci.sh
index b3ed0a0dda..69dff4d1ec 100755
--- a/ci/lib-travisci.sh
+++ b/ci/lib-travisci.sh
@@ -16,13 +16,114 @@ skip_branch_tip_with_tag () {
 	if TAG=$(git describe --exact-match "$TRAVIS_BRANCH" 2>/dev/null) &&
 		test "$TAG" != "$TRAVIS_BRANCH"
 	then
-		echo "Tip of $TRAVIS_BRANCH is exactly at $TAG"
+		echo "$(tput setaf 2)Tip of $TRAVIS_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$(tput sgr0)"
+		false
+	}
+}
+
 # Set 'exit on error' for all CI scripts to let the caller know that
-# something went wrong
-set -e
+# something went wrong.
+# Set tracing executed commands, primarily setting environment variables
+# and installing dependencies.
+set -ex
+
+cache_dir="$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