Remove bases from attributes once they are finalized. (#3608)

This improves performance and also fixes potential bugs where
codegen algorithms make modifications to base types that are
not reflected in dups created for example when projecting views.

expr/attribute.go

@@ -320,6 +320,12 @@ func (a *AttributeExpr) Finalize() {
 			}
 			a.Merge(ru.Attribute())
 		}
+
+		// Now that we've merged the bases, we can clear them.  This
+		// avoids issues where the bases are dupped and modifications
+		// made to the originals are not reflected in the dups.
+		a.Bases = nil
+
 		for _, nat := range *AsObject(a.Type) {
 			if pkgPath != "" {
 				if u := AsUnion(nat.Attribute.Type); u != nil {

http/codegen/server_decode_test.go

@@ -165,6 +165,7 @@ func TestDecode(t *testing.T) {
 		{"decode-body-map-string-validate", testdata.PayloadBodyMapStringValidateDSL, testdata.PayloadBodyMapStringValidateDecodeCode},
 		{"decode-body-map-user", testdata.PayloadBodyMapUserDSL, testdata.PayloadBodyMapUserDecodeCode},
 		{"decode-body-map-user-validate", testdata.PayloadBodyMapUserValidateDSL, testdata.PayloadBodyMapUserValidateDecodeCode},
+		{"decode-deep-user", testdata.PayloadDeepUserDSL, testdata.PayloadDeepUserDecodeCode},
 
 		{"decode-body-primitive-string-validate", testdata.PayloadBodyPrimitiveStringValidateDSL, testdata.PayloadBodyPrimitiveStringValidateDecodeCode},
 		{"decode-body-primitive-bool-validate", testdata.PayloadBodyPrimitiveBoolValidateDSL, testdata.PayloadBodyPrimitiveBoolValidateDecodeCode},

http/codegen/testdata/payload_decode_functions.go

@@ -4338,6 +4338,22 @@ func DecodeMethodBodyMapUserValidateRequest(mux goahttp.Muxer, decoder func(*htt
 }
 `
 
+var PayloadDeepUserDecodeCode = `// marshalServicedeepuserviewsImmediatechildextenderViewToImmediatechildextenderResponseBody
+// builds a value of type *ImmediatechildextenderResponseBody from a value of
+// type *servicedeepuserviews.ImmediatechildextenderView.
+func marshalServicedeepuserviewsImmediatechildextenderViewToImmediatechildextenderResponseBody(v *servicedeepuserviews.ImmediatechildextenderView) *ImmediatechildextenderResponseBody {
+	if v == nil {
+		return nil
+	}
+	res := &ImmediatechildextenderResponseBody{}
+	if v.DeepChild != nil {
+		res.DeepChild = marshalServicedeepuserviewsDeepchildViewToDeepchildResponseBody(v.DeepChild)
+	}
+
+	return res
+}
+`
+
 var PayloadBodyPrimitiveStringValidateDecodeCode = `// DecodeMethodBodyPrimitiveStringValidateRequest returns a decoder for
 // requests sent to the ServiceBodyPrimitiveStringValidate
 // MethodBodyPrimitiveStringValidate endpoint.

http/codegen/testdata/payload_dsls.go

@@ -2301,6 +2301,40 @@ var PayloadBodyMapUserValidateDSL = func() {
 	})
 }
 
+var PayloadDeepUserDSL = func() {
+	var DeepChild = ResultType("DeepChild", func() {
+		Attribute("name", String)
+	})
+	var ImmediateChild = ResultType("ImmediateChild", func() {
+		Attributes(func() {
+			Attribute("deep_child", DeepChild)
+		})
+		View("other", func() {
+			Attribute("deep_child")
+		})
+	})
+	var ImmediateChildExtender = ResultType("ImmediateChildExtender", func() {
+		Extend(ImmediateChild)
+		Attributes(func() {
+			Attribute("deep_child", DeepChild)
+		})
+		View("other", func() {
+			Attribute("deep_child")
+		})
+	})
+	var TopLevel = ResultType("TopLevel", func() {
+		Attributes(func() {
+			Attribute("immediate_child", ImmediateChildExtender)
+		})
+	})
+	Service("ServiceDeepUser", func() {
+		Method("MethodDeepUser", func() {
+			Result(TopLevel)
+			HTTP(func() { GET("/") })
+		})
+	})
+}
+
 var PayloadBodyPrimitiveStringValidateDSL = func() {
 	Service("ServiceBodyPrimitiveStringValidate", func() {
 		Method("MethodBodyPrimitiveStringValidate", func() {