Query and form parameters whose value contains = are truncated or rejected as malformed

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/FormParameters.java

@@ -6,8 +6,6 @@
 
 import java.io.UnsupportedEncodingException;
 import java.net.URLDecoder;
-import java.util.LinkedList;
-import java.util.List;
 import java.util.Scanner;
 
 import org.springframework.util.LinkedMultiValueMap;
@@ -16,6 +14,7 @@
  * A request's form parameters, derived from its form URL encoded body content.
  *
  * @author Andy Wilkinson
+ * @author Minju Kim
  * @since 3.0.0
  */
 public final class FormParameters extends LinkedMultiValueMap<String, String> {
@@ -54,20 +53,12 @@ private static FormParameters parse(String bodyContent) {
 	}
 
 	private static void processParameter(String parameter, FormParameters parameters) {
-		String[] components = parameter.split("=");
-		if (components.length > 0 && components.length < 3) {
-			if (components.length == 2) {
-				String name = components[0];
-				String value = components[1];
-				parameters.add(decode(name), decode(value));
-			}
-			else {
-				List<String> values = parameters.computeIfAbsent(components[0], (p) -> new LinkedList<>());
-				values.add("");
-			}
+		int separator = parameter.indexOf('=');
+		if (separator != -1) {
+			parameters.add(decode(parameter.substring(0, separator)), decode(parameter.substring(separator + 1)));
 		}
 		else {
-			throw new IllegalArgumentException("The parameter '" + parameter + "' is malformed");
+			parameters.add(decode(parameter), "");
 		}
 	}
 

spring-restdocs-core/src/main/java/org/springframework/restdocs/operation/QueryParameters.java

@@ -6,8 +6,6 @@
 
 import java.net.URLDecoder;
 import java.nio.charset.StandardCharsets;
-import java.util.LinkedList;
-import java.util.List;
 import java.util.Scanner;
 
 import org.springframework.util.LinkedMultiValueMap;
@@ -16,6 +14,7 @@
  * A request's query parameters, derived from its URI's query string.
  *
  * @author Andy Wilkinson
+ * @author Minju Kim
  * @since 3.0.0
  */
 public final class QueryParameters extends LinkedMultiValueMap<String, String> {
@@ -54,20 +53,12 @@ private static QueryParameters parse(String query) {
 	}
 
 	private static void processParameter(String parameter, QueryParameters parameters) {
-		String[] components = parameter.split("=");
-		if (components.length > 0 && components.length < 3) {
-			if (components.length == 2) {
-				String name = components[0];
-				String value = components[1];
-				parameters.add(decode(name), decode(value));
-			}
-			else {
-				List<String> values = parameters.computeIfAbsent(components[0], (p) -> new LinkedList<>());
-				values.add("");
-			}
+		int separator = parameter.indexOf('=');
+		if (separator != -1) {
+			parameters.add(decode(parameter.substring(0, separator)), decode(parameter.substring(separator + 1)));
 		}
 		else {
-			throw new IllegalArgumentException("The parameter '" + parameter + "' is malformed");
+			parameters.add(decode(parameter), "");
 		}
 	}
 

spring-restdocs-core/src/test/java/org/springframework/restdocs/operation/FormParametersTests.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2014-present the original author or authors.
+ */
+
+package org.springframework.restdocs.operation;
+
+import java.net.URI;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link FormParameters}.
+ *
+ * @author Minju Kim
+ */
+class FormParametersTests {
+
+	@Test
+	void noContent() {
+		FormParameters parameters = formParameters("");
+		assertThat(parameters).isEmpty();
+	}
+
+	@Test
+	void singleParameter() {
+		FormParameters parameters = formParameters("a=alpha");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("alpha");
+	}
+
+	@Test
+	void multipleParameters() {
+		FormParameters parameters = formParameters("a=alpha&b=bravo&a=apple");
+		assertThat(parameters).containsOnlyKeys("a", "b");
+		assertThat(parameters.get("a")).containsExactly("alpha", "apple");
+		assertThat(parameters.get("b")).containsExactly("bravo");
+	}
+
+	@Test
+	void parameterWithNoValue() {
+		FormParameters parameters = formParameters("a");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("");
+	}
+
+	@Test
+	void parameterWithEmptyValue() {
+		FormParameters parameters = formParameters("a=");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("");
+	}
+
+	@Test
+	void encodedParameter() {
+		FormParameters parameters = formParameters("a+b=c%26d");
+		assertThat(parameters).containsOnlyKeys("a b");
+		assertThat(parameters.get("a b")).containsExactly("c&d");
+	}
+
+	@Test
+	void encodedParameterWithNoValue() {
+		FormParameters parameters = formParameters("a+b");
+		assertThat(parameters).containsOnlyKeys("a b");
+		assertThat(parameters.get("a b")).containsExactly("");
+	}
+
+	@Test
+	void parameterWithValueContainingEquals() {
+		FormParameters parameters = formParameters("filter=name==bob");
+		assertThat(parameters).containsOnlyKeys("filter");
+		assertThat(parameters.get("filter")).containsExactly("name==bob");
+	}
+
+	@Test
+	void parameterWithValueEndingWithEquals() {
+		FormParameters parameters = formParameters("cursor=YWJj==");
+		assertThat(parameters).containsOnlyKeys("cursor");
+		assertThat(parameters.get("cursor")).containsExactly("YWJj==");
+	}
+
+	private FormParameters formParameters(String content) {
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
+		return FormParameters.from(new OperationRequestFactory().create(URI.create("http://localhost"), HttpMethod.POST,
+				content.getBytes(StandardCharsets.UTF_8), headers, Collections.emptyList()));
+	}
+
+}

spring-restdocs-core/src/test/java/org/springframework/restdocs/operation/QueryParametersTests.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright 2014-present the original author or authors.
+ */
+
+package org.springframework.restdocs.operation;
+
+import java.net.URI;
+import java.util.Collections;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link QueryParameters}.
+ *
+ * @author Minju Kim
+ */
+class QueryParametersTests {
+
+	@Test
+	void noQueryString() {
+		QueryParameters parameters = queryParameters("http://localhost");
+		assertThat(parameters).isEmpty();
+	}
+
+	@Test
+	void singleParameter() {
+		QueryParameters parameters = queryParameters("http://localhost?a=alpha");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("alpha");
+	}
+
+	@Test
+	void multipleParameters() {
+		QueryParameters parameters = queryParameters("http://localhost?a=alpha&b=bravo&a=apple");
+		assertThat(parameters).containsOnlyKeys("a", "b");
+		assertThat(parameters.get("a")).containsExactly("alpha", "apple");
+		assertThat(parameters.get("b")).containsExactly("bravo");
+	}
+
+	@Test
+	void parameterWithNoValue() {
+		QueryParameters parameters = queryParameters("http://localhost?a");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("");
+	}
+
+	@Test
+	void parameterWithEmptyValue() {
+		QueryParameters parameters = queryParameters("http://localhost?a=");
+		assertThat(parameters).containsOnlyKeys("a");
+		assertThat(parameters.get("a")).containsExactly("");
+	}
+
+	@Test
+	void encodedParameter() {
+		QueryParameters parameters = queryParameters("http://localhost?a%20b=c%26d");
+		assertThat(parameters).containsOnlyKeys("a b");
+		assertThat(parameters.get("a b")).containsExactly("c&d");
+	}
+
+	@Test
+	void encodedParameterWithNoValue() {
+		QueryParameters parameters = queryParameters("http://localhost?a%20b");
+		assertThat(parameters).containsOnlyKeys("a b");
+		assertThat(parameters.get("a b")).containsExactly("");
+	}
+
+	@Test
+	void parameterWithValueContainingEquals() {
+		QueryParameters parameters = queryParameters("http://localhost?filter=name==bob");
+		assertThat(parameters).containsOnlyKeys("filter");
+		assertThat(parameters.get("filter")).containsExactly("name==bob");
+	}
+
+	@Test
+	void parameterWithValueEndingWithEquals() {
+		QueryParameters parameters = queryParameters("http://localhost?cursor=YWJj==");
+		assertThat(parameters).containsOnlyKeys("cursor");
+		assertThat(parameters.get("cursor")).containsExactly("YWJj==");
+	}
+
+	private QueryParameters queryParameters(String uri) {
+		return QueryParameters.from(new OperationRequestFactory().create(URI.create(uri), HttpMethod.GET, new byte[0],
+				new HttpHeaders(), Collections.emptyList()));
+	}
+
+}

spring-restdocs-mockmvc/src/main/java/org/springframework/restdocs/mockmvc/MockMvcRequestConverter.java

@@ -12,7 +12,6 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -46,6 +45,7 @@
  *
  * @author Andy Wilkinson
  * @author Clyde Stubbs
+ * @author Minju Kim
  */
 class MockMvcRequestConverter implements RequestConverter<MockHttpServletRequest> {
 
@@ -254,20 +254,12 @@ private static MultiValueMap<String, String> parse(@Nullable String query) {
 	}
 
 	private static void processParameter(String parameter, MultiValueMap<String, String> parameters) {
-		String[] components = parameter.split("=");
-		if (components.length > 0 && components.length < 3) {
-			if (components.length == 2) {
-				String name = components[0];
-				String value = components[1];
-				parameters.add(decode(name), decode(value));
-			}
-			else {
-				List<String> values = parameters.computeIfAbsent(components[0], (p) -> new LinkedList<>());
-				values.add("");
-			}
+		int separator = parameter.indexOf('=');
+		if (separator != -1) {
+			parameters.add(decode(parameter.substring(0, separator)), decode(parameter.substring(separator + 1)));
 		}
 		else {
-			throw new IllegalArgumentException("The parameter '" + parameter + "' is malformed");
+			parameters.add(decode(parameter), "");
 		}
 	}
 

spring-restdocs-mockmvc/src/test/java/org/springframework/restdocs/mockmvc/MockMvcRequestConverterTests.java

@@ -159,6 +159,24 @@ void postRequestWithNonAsciiParametersAndQueryStringCreatesFormUrlEncodedContent
 		assertThat(request.getHeaders().getContentType()).isEqualTo(MediaType.APPLICATION_FORM_URLENCODED);
 	}
 
+	@Test
+	void postRequestWithQueryStringParameterWithValueContainingEquals() {
+		OperationRequest request = createOperationRequest(
+				MockMvcRequestBuilders.post(URI.create("/foo?filter=name==bob")));
+		assertThat(request.getUri()).isEqualTo(URI.create("http://localhost/foo?filter=name==bob"));
+		assertThat(request.getMethod()).isEqualTo(HttpMethod.POST);
+		assertThat(request.getContentAsString()).isEmpty();
+	}
+
+	@Test
+	void postRequestWithQueryStringParameterWithValueEndingWithEqualsDoesNotDuplicateItInContent() {
+		OperationRequest request = createOperationRequest(
+				MockMvcRequestBuilders.post(URI.create("/foo?cursor=YWJj==")));
+		assertThat(request.getUri()).isEqualTo(URI.create("http://localhost/foo?cursor=YWJj=="));
+		assertThat(request.getMethod()).isEqualTo(HttpMethod.POST);
+		assertThat(request.getContentAsString()).isEmpty();
+	}
+
 	@Test
 	void mockMultipartFileUpload() {
 		OperationRequest request = createOperationRequest(MockMvcRequestBuilders.multipart("/foo")