如何理解这个Go makefile？

COVERPROFILE=cover.out

default: test

cover:
    go test -coverprofile=$(COVERPROFILE) .
    go tool cover -html=$(COVERPROFILE)
    rm $(COVERPROFILE)

dependencies:
    go get -d .

test:
    go test -i ./...
    go test -v ./...

.PHONY: coverage dependencies test

I don't understand this golang makefile. Is there any tutorial for golang makefiles? I searched Google and didn't find any complete one. For example, I don't see any explanation for what is "cover," etc.