make GO111MODULE=on default on makefile

Makefile

@@ -1,6 +1,6 @@
 DIST := dist
 IMPORT := code.gitea.io/gitea
-export GO111MODULE=off
+export GO111MODULE=on
 
 GO ?= go
 SED_INPLACE := sed -i
@@ -97,12 +97,12 @@ vet:
 
 .PHONY: generate
 generate:
-	GO111MODULE=on $(GO) generate -mod=vendor $(PACKAGES)
+	$(GO) generate -mod=vendor $(PACKAGES)
 
 .PHONY: generate-swagger
 generate-swagger:
 	@hash swagger > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
-		GO111MODULE="on" $(GO) get -u github.com/go-swagger/go-swagger/cmd/swagger@v0.19.0; \
+		$(GO) get -u github.com/go-swagger/go-swagger/cmd/swagger@v0.19.0; \
 	fi
 	swagger generate spec -o './$(SWAGGER_SPEC)'
 	$(SED_INPLACE) '$(SWAGGER_SPEC_S_TMPL)' './$(SWAGGER_SPEC)'
@@ -170,7 +170,7 @@ fmt-check:
 
 .PHONY: test
 test:
-	GO111MODULE=on $(GO) test -mod=vendor -tags='sqlite sqlite_unlock_notify' $(PACKAGES)
+	$(GO) test -mod=vendor -tags='sqlite sqlite_unlock_notify' $(PACKAGES)
 
 .PHONY: coverage
 coverage:
@@ -185,7 +185,7 @@ unit-test-coverage:
 
 .PHONY: vendor
 vendor:
-	GO111MODULE=on $(GO) mod tidy && GO111MODULE=on $(GO) mod vendor
+	$(GO) mod tidy && $(GO) mod vendor
 
 .PHONY: test-vendor
 test-vendor: vendor
@@ -285,34 +285,34 @@ integration-test-coverage: integrations.cover.test generate-ini
 	GITEA_ROOT=${CURDIR} GITEA_CONF=integrations/mysql.ini ./integrations.cover.test -test.coverprofile=integration.coverage.out
 
 integrations.test: $(SOURCES)
-	GO111MODULE=on $(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -o integrations.test
+	$(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -o integrations.test
 
 integrations.sqlite.test: $(SOURCES)
-	GO111MODULE=on $(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -o integrations.sqlite.test -tags 'sqlite sqlite_unlock_notify'
+	$(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -o integrations.sqlite.test -tags 'sqlite sqlite_unlock_notify'
 
 integrations.cover.test: $(SOURCES)
-	GO111MODULE=on $(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -coverpkg $(shell echo $(PACKAGES) | tr ' ' ',') -o integrations.cover.test
+	$(GO) test -mod=vendor -c code.gitea.io/gitea/integrations -coverpkg $(shell echo $(PACKAGES) | tr ' ' ',') -o integrations.cover.test
 
 .PHONY: migrations.test
 migrations.test: $(SOURCES)
-	$(GO) test -c code.gitea.io/gitea/integrations/migration-test -o migrations.test
+	$(GO) test -mod=vendor -c code.gitea.io/gitea/integrations/migration-test -o migrations.test
 
 .PHONY: migrations.sqlite.test
 migrations.sqlite.test: $(SOURCES)
-	$(GO) test -c code.gitea.io/gitea/integrations/migration-test -o migrations.sqlite.test -tags 'sqlite sqlite_unlock_notify'
+	$(GO) test -mod=vendor -c code.gitea.io/gitea/integrations/migration-test -o migrations.sqlite.test -tags 'sqlite sqlite_unlock_notify'
 
 .PHONY: check
 check: test
 
 .PHONY: install
 install: $(wildcard *.go)
-	$(GO) install -v -tags '$(TAGS)' -ldflags '-s -w $(LDFLAGS)'
+	$(GO) install -mod=vendor -v -tags '$(TAGS)' -ldflags '-s -w $(LDFLAGS)'
 
 .PHONY: build
 build: $(EXECUTABLE)
 
 $(EXECUTABLE): $(SOURCES)
-	GO111MODULE=on $(GO) build -mod=vendor $(GOFLAGS) $(EXTRA_GOFLAGS) -tags '$(TAGS)' -ldflags '-s -w $(LDFLAGS)' -o $@
+	$(GO) build -mod=vendor $(GOFLAGS) $(EXTRA_GOFLAGS) -tags '$(TAGS)' -ldflags '-s -w $(LDFLAGS)' -o $@
 
 .PHONY: release
 release: release-dirs release-windows release-linux release-darwin release-copy release-compress release-check