1 files changed, 65 insertions, 0 deletions
diff --git a/src/os/exec/env_test.go b/src/os/exec/env_test.go
new file mode 100644
index 0000000..b9e0924
--- /dev/null
+++ b/src/os/exec/env_test.go
@@ -0,0 +1,65 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package exec
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestDedupEnv(t *testing.T) {
+	tests := []struct {
+		noCase  bool
+		nulOK   bool
+		in      []string
+		want    []string
+		wantErr bool
+	}{
+		{
+			noCase: true,
+			in:     []string{"k1=v1", "k2=v2", "K1=v3"},
+			want:   []string{"k2=v2", "K1=v3"},
+		},
+		{
+			noCase: false,
+			in:     []string{"k1=v1", "K1=V2", "k1=v3"},
+			want:   []string{"K1=V2", "k1=v3"},
+		},
+		{
+			in:   []string{"=a", "=b", "foo", "bar"},
+			want: []string{"=b", "foo", "bar"},
+		},
+		{
+			// #49886: preserve weird Windows keys with leading "=" signs.
+			noCase: true,
+			in:     []string{`=C:=C:\golang`, `=D:=D:\tmp`, `=D:=D:\`},
+			want:   []string{`=C:=C:\golang`, `=D:=D:\`},
+		},
+		{
+			// #52436: preserve invalid key-value entries (for now).
+			// (Maybe filter them out or error out on them at some point.)
+			in:   []string{"dodgy", "entries"},
+			want: []string{"dodgy", "entries"},
+		},
+		{
+			// Filter out entries containing NULs.
+			in:      []string{"A=a\x00b", "B=b", "C\x00C=c"},
+			want:    []string{"B=b"},
+			wantErr: true,
+		},
+		{
+			// Plan 9 needs to preserve environment variables with NUL (#56544).
+			nulOK: true,
+			in:    []string{"path=one\x00two"},
+			want:  []string{"path=one\x00two"},
+		},
+	}
+	for _, tt := range tests {
+		got, err := dedupEnvCase(tt.noCase, tt.nulOK, tt.in)
+		if !reflect.DeepEqual(got, tt.want) || (err != nil) != tt.wantErr {
+			t.Errorf("Dedup(%v, %q) = %q, %v; want %q, error:%v", tt.noCase, tt.in, got, err, tt.want, tt.wantErr)
+		}
+	}
+}