[travis] check module deps

Signed-off-by: Brian Goff <[email protected]>

.travis.yml

@@ -7,12 +7,16 @@ go:
   - "stable"
   - tip
 
+env:
+  - GO111MODULE: "on"
+
 matrix:
   allow_failures:
     - go: tip
 
 script:
-  - if [ "${TRAVIS_GO_VERSION}" = "stable" ]; then make golangci-lint
+  - if [ "${TRAVIS_GO_VERSION}" = "stable" ]; then make check-mod; fi
+  - if [ "${TRAVIS_GO_VERSION}" = "stable" ]; then make golangci-lint; fi
   - if [ "${TRAVIS_GO_VERSION}" = "stable" ]; then echo running check scripts; make check; fi
   - make build
   - make TEST_FLAGS="-v" test

Makefile

@@ -1,5 +1,8 @@
+GO111MODULE ?= on
 LINTER_BIN ?= golangci-lint
 
+export GO111MODULE
+
 .PHONY:
 build: bin/go-md2man
 
@@ -31,3 +34,15 @@ $(LINTER_BIN):
 		curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | sh -s -- -b $(shell go env GOPATH)/bin v1.15.0; \
 	fi
 
+.PHONY: mod
+mod:
+	@go mod tidy
+
+.PHONY: check-mod
+check-mod: # verifies that module changes for go.mod and go.sum are checked in
+	@hack/ci/check_mods.sh
+
+.PHONY: vendor
+vendor: mod
+	@go mod vendor -v
+