require "utils/popen" describe Utils do describe "::popen_read" do it "reads the standard output of a given command" do expect(subject.popen_read("sh", "-c", "echo success").chomp).to eq("success") expect($CHILD_STATUS).to be_a_success end it "can be given a block to manually read from the pipe" do expect( subject.popen_read("sh", "-c", "echo success") do |pipe| pipe.read.chomp end, ).to eq("success") expect($CHILD_STATUS).to be_a_success end it "fails when the command does not exist" do expect(subject.popen_read("./nonexistent", err: :out)) .to eq("brew: command not found: ./nonexistent\n") expect($CHILD_STATUS).to be_a_failure end end describe "::popen_write" do it "with supports writing to a command's standard input" do subject.popen_write("grep", "-q", "success") do |pipe| pipe.write("success\n") end expect($CHILD_STATUS).to be_a_success end end end