Add missing tools.go

Also rearrange the code to be more consistent.

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

.circleci/config.yml

@@ -16,7 +16,7 @@ jobs:
     steps:
     - checkout
     - run: make promu
-    - run: make check_license staticcheck style unused build
+    - run: make check_license style unused staticcheck build
     - run: git diff --exit-code
     - store_artifacts:
         path: prometheus

.travis.yml

@@ -10,5 +10,5 @@ go:
 go_import_path: github.com/prometheus/prometheus
 
 script:
-- make check_license staticcheck style unused test
+- make check_license style unused test staticcheck
 - git diff --exit-code

Makefile.common

@@ -45,7 +45,6 @@ $(warning Some recipes may not work as expected as the current Go runtime is '$(
 else
 # This repository isn't using Go modules (yet).
 	GOVENDOR    := $(FIRST_GOPATH)/bin/govendor
-	STATICCHECK := $(FIRST_GOPATH)/bin/staticcheck
 	GO111MODULE := auto
 endif
 PROMU        := $(FIRST_GOPATH)/bin/promu
@@ -108,16 +107,15 @@ common-vet:
 .PHONY: common-staticcheck
 common-staticcheck: $(STATICCHECK)
 	@echo ">> running staticcheck"
-ifdef STATICCHECK
-	GO111MODULE=off $(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs)
+ifeq (,$(wildcard go.mod))
+	$(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs)
 else
-	GO111MODULE=$(GO111MODULE) $(GO) install -v $(GOOPTS) honnef.co/go/tools/cmd/staticcheck
-	$(FIRST_GOPATH)/bin/staticcheck -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs)
+	GO111MODULE=$(GO111MODULE) $(GO) run $(GOOPTS) honnef.co/go/tools/cmd/staticcheck -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs)
 endif
 
 .PHONY: common-unused
 common-unused: $(GOVENDOR)
-ifdef GOVENDOR
+ifeq (,$(wildcard go.mod))
 	@echo ">> running check for unused packages"
 	@$(GOVENDOR) list +unused | grep . && exit 1 || echo 'No unused packages'
 else
@@ -155,7 +153,7 @@ common-docker-tag-latest:
 promu:
 	GOOS= GOARCH= GO111MODULE=off $(GO) get -u github.com/prometheus/promu
 
-ifneq (,$(wildcard go.mod))
+ifeq (,$(wildcard go.mod))
 .PHONY: $(STATICCHECK)
 $(STATICCHECK):
 	GOOS= GOARCH= GO111MODULE=off $(GO) get -u honnef.co/go/tools/cmd/staticcheck

util/tools/tools.go

@@ -0,0 +1,24 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Imports of tools we want "go mod vendor" to include.
+// https://github.com/golang/go/issues/25624#issuecomment-395556484
+// https://github.com/golang/go/issues/25922
+
+// +build tools
+
+package tools
+
+import (
+	_ "honnef.co/go/tools/cmd/staticcheck"
+)