执行单个目录所有测试用例并生成覆盖率
go test -gcflags=all=-l -coverprofile=$GOPATH/bin/c.out .
go tool cover -html=$GOPATH/bin/c.out -o=$GOPATH/bin/tag.html
执行单个测试用例并生成覆盖率
go test -gcflags=all=-l -v -run="TestHelloWorld" -coverprofile=$GOPATH/bin/c.out
go tool cover -html=$GOPATH/bin/c.out -o=$GOPATH/bin/tag.html