cmd/go: cannot use 'go test' with code depending on TERM variable

[ericwq]

if you run the following simple test code under 1.5rc1

func TestTermEnv(t *testing.T) {
    fmt.Printf("%s\n",os.Getenv("TERM"))
}

you will get the wrong TERM variable, while the correct result should be "xterm" prefixed.

$go test
dumb

the environment:

$ uname -a
Darwin wangs-MacBook.local 14.4.0 Darwin Kernel Version 14.4.0: Thu May 28 11:35:04 PDT 2015; root:xnu-2782.30.5~1/RELEASE_X86_64 x86_64
$ go version
go version go1.5rc1 darwin/amd64
$ env | grep TERM
TERM_PROGRAM=Apple_Terminal
TERM=xterm-256color
TERM_PROGRAM_VERSION=343.7
TERM_SESSION_ID=0033F701-265E-4DF7-B4DA-2FD9C735BD4A

i notice there is a default "dumb" value for TERM env. is this the correct default value?
the previous issue #11449 only solve the "go run" case.

[rsc]

This is the second environment bug we've had because the compilation environment leaked into execution. We probably need separate environments.

[gopherbot]

CL https://golang.org/cl/13449 mentions this issue.