Prevent double encoding in stripPrefix method

The stripPrefix method was causing URLs to be encoded twice under certain conditions.
This fix ensures proper handling of parameters to avoid redundant encoding.

Signed-off-by: raccoonback <[email protected]>

Author: raccoonback

spring-cloud-gateway-server-mvc/src/main/java/org/springframework/cloud/gateway/server/mvc/filter/BeforeFilterFunctions.java

@@ -409,7 +409,7 @@ public static Function<ServerRequest, ServerRequest> stripPrefix(int parts) {
 
 			URI prefixedUri = UriComponentsBuilder.fromUri(request.uri())
 				.replacePath(newPath.toString())
-				.build()
+				.build(true)
 				.toUri();
 			return ServerRequest.from(request).uri(prefixedUri).build();
 		};

spring-cloud-gateway-server-mvc/src/test/java/org/springframework/cloud/gateway/server/mvc/filter/BeforeFilterFunctionsTests.java

@@ -157,4 +157,42 @@ void setPathWithEncodedParameters() {
 		assertThat(result.uri().toString()).isEqualTo("http://localhost/new/path?foo%5B%5D=bar%5B%5D");
 	}
 
+	@Test
+	void stripPrefix() {
+		MockHttpServletRequest servletRequest = MockMvcRequestBuilders.get("http://localhost/depth1/depth2/depth3")
+				.buildRequest(null);
+
+		ServerRequest request = ServerRequest.create(servletRequest, Collections.emptyList());
+
+		ServerRequest result = BeforeFilterFunctions.stripPrefix(2).apply(request);
+
+		assertThat(result.uri().toString()).isEqualTo("http://localhost/depth3");
+	}
+
+	@Test
+	void stripPrefixWithEncodedPath() {
+		MockHttpServletRequest servletRequest = MockMvcRequestBuilders.get("http://localhost/depth1/depth2/depth3/é")
+				.buildRequest(null);
+
+		ServerRequest request = ServerRequest.create(servletRequest, Collections.emptyList());
+
+		ServerRequest result = BeforeFilterFunctions.stripPrefix(2).apply(request);
+
+		assertThat(result.uri().toString()).isEqualTo("http://localhost/depth3/%C3%A9");
+	}
+
+	@Test
+	void stripPrefixWithEncodedParameters() {
+		MockHttpServletRequest servletRequest = MockMvcRequestBuilders.get("http://localhost/depth1/depth2/depth3")
+				.queryParam("baz[]", "qux[]")
+				.buildRequest(null);
+
+		ServerRequest request = ServerRequest.create(servletRequest, Collections.emptyList());
+
+		ServerRequest result = BeforeFilterFunctions.stripPrefix(2).apply(request);
+
+		assertThat(result.param("baz[]")).isPresent().hasValue("qux[]");
+		assertThat(result.uri().toString()).isEqualTo("http://localhost/depth3?baz%5B%5D=qux%5B%5D");
+	}
+
 }