undo append operations

request_modifiers.go

@@ -246,12 +246,7 @@ func (m *requestModifiers) additionalQueryParametersOrDefault() url.Values {
 	return m.additionalQueryParameters
 }
 
-// mergeRequestModifiers merges the values in *rhs into *lhs. The merging is
-// done according the following rules:
-//
-//   - for scalaras : the rhs values, if present, will overwrite the lhs values
-//   - for slices   : the rhs values will be appended to the lhs values
-//   - for maps     : the rhs values will be copied into the lhs using maps.Copy
+// mergeRequestModifiers merges the values from *rhs into *lhs.
 func mergeRequestModifiers(lhs, rhs *requestModifiers) {
 	if rhs.headers.userAgent != "" {
 		lhs.headers.userAgent = rhs.headers.userAgent
@@ -265,10 +260,9 @@ func mergeRequestModifiers(lhs, rhs *requestModifiers) {
 		lhs.headers.namespace = rhs.headers.namespace
 	}
 
-	lhs.headers.mfaCredentials = append(
-		lhs.headers.mfaCredentials,
-		rhs.headers.mfaCredentials...,
-	)
+	if len(rhs.headers.mfaCredentials) != 0 {
+		lhs.headers.mfaCredentials = rhs.headers.mfaCredentials
+	}
 
 	if rhs.headers.responseWrappingTTL != 0 {
 		lhs.headers.responseWrappingTTL = rhs.headers.responseWrappingTTL
@@ -278,18 +272,17 @@ func mergeRequestModifiers(lhs, rhs *requestModifiers) {
 		lhs.headers.replicationForwardingMode = rhs.headers.replicationForwardingMode
 	}
 
-	// in case of key collisions, the rhs keys will take precedence
-	maps.Copy(lhs.headers.customHeaders, rhs.headers.customHeaders)
+	if len(rhs.headers.customHeaders) != 0 {
+		lhs.headers.customHeaders = rhs.headers.customHeaders
+	}
 
-	lhs.requestCallbacks = append(
-		lhs.requestCallbacks,
-		rhs.requestCallbacks...,
-	)
+	if len(rhs.requestCallbacks) != 0 {
+		lhs.requestCallbacks = rhs.requestCallbacks
+	}
 
-	lhs.responseCallbacks = append(
-		lhs.responseCallbacks,
-		rhs.responseCallbacks...,
-	)
+	if len(rhs.responseCallbacks) != 0 {
+		lhs.responseCallbacks = rhs.responseCallbacks
+	}
 }
 
 func validateToken(token string) error {

request_modifiers_test.go

@@ -130,50 +130,3 @@ func Test_mergeRequestModifiers_overwrite(t *testing.T) {
 		})
 	}
 }
-
-func Test_mergeRequestModifiers_append(t *testing.T) {
-	requestCallback1 := func(r *http.Request) {
-		t.Logf("callback 1: %v", *r)
-	}
-	requestCallback2 := func(r *http.Request) {
-		t.Logf("callback 2: %v", *r)
-	}
-	responseCallback := func(req *http.Request, resp *http.Response) {
-		t.Logf("callback 3: %v, %v", *req, *resp)
-	}
-
-	cases := map[string]struct {
-		name     string
-		lhs      requestModifiers
-		rhs      requestModifiers
-		expected requestModifiers
-	}{
-		"custom-headers": {
-			lhs:      requestModifiers{headers: requestHeaders{customHeaders: http.Header{"a": []string{"hi"}, "b": nil}}},
-			rhs:      requestModifiers{headers: requestHeaders{customHeaders: http.Header{"b": nil, "c": nil}}},
-			expected: requestModifiers{headers: requestHeaders{customHeaders: http.Header{"a": []string{"hi"}, "b": nil, "c": nil}}},
-		},
-		"request-callbacks": {
-			lhs:      requestModifiers{requestCallbacks: []RequestCallback{requestCallback1}},
-			rhs:      requestModifiers{requestCallbacks: []RequestCallback{requestCallback2}},
-			expected: requestModifiers{requestCallbacks: []RequestCallback{requestCallback1, requestCallback2}},
-		},
-		"response-callbacks": {
-			lhs:      requestModifiers{responseCallbacks: []ResponseCallback{}},
-			rhs:      requestModifiers{responseCallbacks: []ResponseCallback{responseCallback}},
-			expected: requestModifiers{responseCallbacks: []ResponseCallback{responseCallback}},
-		},
-	}
-
-	for name, tc := range cases {
-		t.Run(name, func(t *testing.T) {
-			mergeRequestModifiers(&tc.lhs, &tc.rhs)
-
-			// testify doesn't currently work with func types; stringify instead
-			require.Equal(t, fmt.Sprintf("%v", tc.expected.requestCallbacks), fmt.Sprintf("%v", tc.lhs.requestCallbacks))
-			require.Equal(t, fmt.Sprintf("%v", tc.expected.responseCallbacks), fmt.Sprintf("%v", tc.lhs.responseCallbacks))
-
-			require.Equal(t, tc.expected.headers.customHeaders, tc.lhs.headers.customHeaders)
-		})
-	}
-}