Merge pull request #4092 from mitchellh/gofmt

Gofmt

Makefile

@@ -4,6 +4,7 @@ VET?=$(shell ls -d */ | grep -v vendor | grep -v website)
 GITSHA:=$(shell git rev-parse HEAD)
 # Get the current local branch name from git (if we can, this may be blank)
 GITBRANCH:=$(shell git symbolic-ref --short HEAD 2>/dev/null)
+GOFMT_FILES?=$$(find . -not -path "./vendor/*" -name "*.go")
 
 default: deps generate test dev
 
@@ -40,7 +41,10 @@ dev: deps ## Build and install a development build
 	@PACKER_DEV=1 GO15VENDOREXPERIMENT=1 sh -c "$(CURDIR)/scripts/build.sh"
 
 fmt: ## Format Go code
-	@gofmt -s -w `go list -f {{.Dir}} ./... | grep -v "/vendor/"`
+	@gofmt -w -s $(GOFMT_FILES)
+
+fmt-check: ## Check go code formatting
+	$(CURDIR)/scripts/gofmtcheck.sh $(GOFMT_FILES)
 
 # Install js-beautify with npm install -g js-beautify
 fmt-examples:
@@ -52,7 +56,7 @@ generate: deps ## Generate dynamically generated code
 	go generate .
 	gofmt -w command/plugin.go
 
-test: deps ## Run unit tests
+test: deps fmt-check ## Run unit tests
 	@go test $(TEST) $(TESTARGS) -timeout=2m
 	@go tool vet $(VET)  ; if [ $$? -eq 1 ]; then \
 		echo "ERROR: Vet found problems in the code."; \

scripts/gofmtcheck.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+
+# Check gofmt
+echo "==> Checking that code complies with gofmt requirements..."
+gofmt_files=$(gofmt -s -l ${@})
+if [[ -n ${gofmt_files} ]]; then
+    echo 'gofmt needs running on the following files:'
+    echo "${gofmt_files}"
+    echo "You can use the command: \`make fmt\` to reformat code."
+    exit 1
+fi
+echo "Check passed."
+
+exit 0