container/autoetc: do not bypass absolute check

This can now be done cleanly via path function wrappers.

Signed-off-by: Ophestra <cat@gensokyo.uk>

container/autoetc.go

@@ -61,8 +61,7 @@ func (e *AutoEtcOp) apply(state *setupState) error {
 	return nil
 }
 
-// bypasses abs check, use with caution!
+func (e *AutoEtcOp) hostPath() *Absolute { return AbsFHSEtc.Append(e.hostRel()) }
-func (e *AutoEtcOp) hostPath() *Absolute { return &Absolute{FHSEtc + e.hostRel()} }
 func (e *AutoEtcOp) hostRel() string     { return ".host/" + e.Prefix }
 
 func (e *AutoEtcOp) Is(op Op) bool {

container/autoetc_test.go

@@ -0,0 +1,40 @@
+package container
+
+import "testing"
+
+func TestAutoEtcOp(t *testing.T) {
+	checkOpsBuilder(t, []opsBuilderTestCase{
+		{"pd", new(Ops).Etc(MustAbs("/etc/"), "048090b6ed8f9ebb10e275ff5d8c0659"), Ops{
+			&MkdirOp{Path: MustAbs("/etc/"), Perm: 0755},
+			&BindMountOp{
+				Source: MustAbs("/etc/"),
+				Target: MustAbs("/etc/.host/048090b6ed8f9ebb10e275ff5d8c0659"),
+			},
+			&AutoEtcOp{Prefix: "048090b6ed8f9ebb10e275ff5d8c0659"},
+		}},
+	})
+
+	checkOpIs(t, []opIsTestCase{
+		{"zero", new(AutoEtcOp), new(AutoEtcOp), true},
+		{"differs", &AutoEtcOp{Prefix: "\x00"}, &AutoEtcOp{":3"}, false},
+		{"equals", &AutoEtcOp{Prefix: ":3"}, &AutoEtcOp{":3"}, true},
+	})
+
+	checkOpMeta(t, []opMetaTestCase{
+		{"etc", &AutoEtcOp{
+			Prefix: ":3",
+		}, "setting up", "auto etc :3"},
+	})
+
+	t.Run("host path rel", func(t *testing.T) {
+		op := &AutoEtcOp{Prefix: "048090b6ed8f9ebb10e275ff5d8c0659"}
+		wantHostPath := "/etc/.host/048090b6ed8f9ebb10e275ff5d8c0659"
+		wantHostRel := ".host/048090b6ed8f9ebb10e275ff5d8c0659"
+		if got := op.hostPath(); got.String() != wantHostPath {
+			t.Errorf("hostPath: %q, want %q", got, wantHostPath)
+		}
+		if got := op.hostRel(); got != wantHostRel {
+			t.Errorf("hostRel: %q, want %q", got, wantHostRel)
+		}
+	})
+}