// MergeEnv merges environment variables in base with those
// in vars according to the suppled policies.
func MergeEnv(policies map[string]MergePolicy, base *envvar.Vars, vars ...[]string) {
// Remove any variables that have the IgnoreBase policy.
for k, _ := range base.ToMap() {
switch policies[k].Action {
case Ignore, IgnoreBaseAndAppend, IgnoreBaseAndPrepend, IgnoreBaseAndUseFirst, IgnoreBaseAndUseLast:
base.Delete(k)
}
}
for _, ev := range vars {
for _, tmp := range ev {
k, v := envvar.SplitKeyValue(tmp)
policy := policies[k]
action := policy.Action
switch policy.Action {
case IgnoreBaseAndAppend:
action = Append
case IgnoreBaseAndPrepend:
action = Prepend
case IgnoreBaseAndUseLast:
action = Last
case IgnoreBaseAndUseFirst:
action = First
}
switch action {
case Ignore, IgnoreProfiles:
continue
case Append, Prepend:
sep := policy.Separator
ov := base.GetTokens(k, sep)
nv := envvar.SplitTokens(v, sep)
if action == Append {
base.SetTokens(k, append(ov, nv...), sep)
} else {
base.SetTokens(k, append(nv, ov...), sep)
}
case First:
if !base.Contains(k) {
base.Set(k, v)
}
case Last:
base.Set(k, v)
}
}
}
}
// UnsetGoEnvVars unsets Go environment variables in the given environment.
func UnsetGoEnvVars(env *envvar.Vars) {
for _, k := range GoFlags {
env.Delete(k)
}
}