add version command to give dep's version

.gitignore

@@ -1 +1,2 @@
-dep
+dep
+build

Makefile

@@ -0,0 +1,64 @@
+# Set an output prefix, which is the local directory if not specified
+PREFIX?=$(shell pwd)
+
+# Setup name variables for the package/tool
+NAME := dep
+PKG := github.com/golang/$(NAME)
+
+# Set any default go build tags
+BUILDTAGS :=
+
+# Set the build dir, where built cross-compiled binaries will be output
+BUILDDIR := ${PREFIX}/build
+
+# Populate version variables
+# Add to compile time flags
+VERSION := $(shell cat VERSION)
+GITCOMMIT := $(shell git rev-parse --short HEAD)
+GITUNTRACKEDCHANGES := $(shell git status --porcelain --untracked-files=no)
+ifneq ($(GITUNTRACKEDCHANGES),)
+	GITCOMMIT := $(GITCOMMIT)-dirty
+endif
+CTIMEVAR=-X main.GITCOMMIT=$(GITCOMMIT) -X main.VERSION=$(VERSION)
+GO_LDFLAGS=-ldflags "-w $(CTIMEVAR)"
+GO_LDFLAGS_STATIC=-ldflags "-w $(CTIMEVAR) -extldflags -static"
+
+# List the GOOS and GOARCH to build
+GOOSARCHES = darwin/amd64 darwin/386 freebsd/amd64 freebsd/386 linux/arm linux/arm64 linux/amd64 linux/386 solaris/amd64 windows/amd64 windows/386
+
+.PHONY: build
+build: $(NAME) ## Builds a dynamic executable
+
+$(NAME): *.go VERSION
+	@echo "+ $@"
+	go build -tags "$(BUILDTAGS)" ${GO_LDFLAGS} -o $(NAME) .
+
+.PHONY: static
+static: ## Builds a static executable
+	@echo "+ $@"
+	CGO_ENABLED=0 go build \
+				-tags "$(BUILDTAGS) static_build" \
+				${GO_LDFLAGS_STATIC} -o $(NAME) .
+
+define buildrelease
+mkdir -p $(BUILDDIR)/$(1)/$(2);
+GOOS=$(1) GOARCH=$(2) CGO_ENABLED=0 go build \
+	 -o $(BUILDDIR)/$(1)/$(2)/$(NAME) \
+	 -a -tags "$(BUILDTAGS) static_build netgo" \
+	 -installsuffix netgo ${GO_LDFLAGS_STATIC} .;
+endef
+
+.PHONY: cross
+cross: *.go VERSION ## Builds the cross-compiled binaries, creating a clean directory structure (eg. GOOS/GOARCH/binary)
+	@echo "+ $@"
+	$(foreach GOOSARCH,$(GOOSARCHES), $(call buildrelease,$(subst /,,$(dir $(GOOSARCH))),$(notdir $(GOOSARCH))))
+
+.PHONY: clean
+clean: ## Cleanup any build binaries
+	@echo "+ $@"
+	$(RM) $(NAME)
+	$(RM) -r $(BUILDDIR)
+
+.PHONY: help
+help:
+	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'

VERSION

@@ -0,0 +1 @@
+0.0.0

main.go

@@ -95,6 +95,7 @@ var commands = []*command{
 	initCmd,
 	statusCmd,
 	ensureCmd,
+	versionCmd,
 	// help added here at init time.
 }
 

version.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"fmt"
+	"runtime"
+)
+
+var (
+	// VERSION indicates which version of the binary is running.
+	VERSION string
+
+	// GITCOMMIT indicates which git hash the binary was built off of
+	GITCOMMIT string
+)
+
+var versionCmd = &command{
+	fn:   runVersion,
+	name: "version",
+	short: `
+	Version prints the version, git commit, runtime OS and ARCH.
+	`,
+	long: `Version prints the version, git commit, runtime OS and ARCH.`,
+}
+
+func runVersion(args []string) error {
+	fmt.Printf("dep version %s %s %s/%s\n", VERSION, GITCOMMIT, runtime.GOOS, runtime.GOARCH)
+	return nil
+}