add more test for var files

hcl2template/common_test.go

@@ -91,6 +91,9 @@ func testParse(t *testing.T, tests []parseTest) {
 						if variable.DefaultValue.GoString() != value.DefaultValue.GoString() {
 							t.Fatalf("Parser.parse() input variable %s expected '%s' but was '%s'", name, value.DefaultValue.GoString(), variable.DefaultValue.GoString())
 						}
+						if diff := cmp.Diff(variable.VarfileValue.GoString(), value.VarfileValue.GoString()); diff != "" {
+							t.Fatalf("Parser.parse(): varfile value differs: %s", diff)
+						}
 					} else {
 						t.Fatalf("Parser.parse() missing input variable. %s", name)
 					}

hcl2template/testdata/variables/foo-string.variable.pkr.hcl

@@ -0,0 +1,4 @@
+variable "foo" {
+    type = string
+    default = "bar"
+}

hcl2template/testdata/variables/set-foo-too-wee.hcl

@@ -0,0 +1 @@
+foo = "wee"

hcl2template/types.variables_test.go

@@ -240,6 +240,35 @@ func TestParse_variables(t *testing.T) {
 			[]packer.Build{},
 			false,
 		},
+
+		{"set variable from var-file",
+			defaultParser,
+			parseTestArgs{"testdata/variables/foo-string.variable.pkr.hcl", nil, []string{"testdata/variables/set-foo-too-wee.hcl"}},
+			&PackerConfig{
+				Basedir: filepath.Join("testdata", "variables"),
+				InputVariables: Variables{
+					"foo": &Variable{
+						DefaultValue: cty.StringVal("bar"),
+						Name:         "foo",
+						VarfileValue: cty.StringVal("wee"),
+					},
+				},
+			},
+			false, false,
+			[]packer.Build{},
+			false,
+		},
+
+		{"unknown variable from var-file",
+			defaultParser,
+			parseTestArgs{"testdata/variables/empty.pkr.hcl", nil, []string{"testdata/variables/set-foo-too-wee.hcl"}},
+			&PackerConfig{
+				Basedir: filepath.Join("testdata", "variables"),
+			},
+			true, false,
+			[]packer.Build{},
+			false,
+		},
 	}
 	testParse(t, tests)
 }