Asserting empty array in the response (#211)

with this change we're using new JSONAssert that allows to check if an array is empty

fixes #203

spring-cloud-contract-dependencies/pom.xml

@@ -15,7 +15,7 @@
 	<description>Spring Cloud Contract Dependencies</description>
 	<properties>
 		<wiremock.version>2.1.7</wiremock.version>
-		<jsonassert.version>0.4.7</jsonassert.version>
+		<jsonassert.version>0.4.8</jsonassert.version>
 		<aether.version>1.0.2.v20150114</aether.version>
 	</properties>
 	<dependencyManagement>

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/main/groovy/org/springframework/cloud/contract/verifier/plugin/SpringCloudContractVerifierGradlePlugin.groovy

@@ -94,7 +94,7 @@ class SpringCloudContractVerifierGradlePlugin implements Plugin<Project> {
 	private void addProjectDependencies(Project project) {
 		//TODO: Consider removing this at some point
 		project.dependencies.add("testCompile", "com.github.tomakehurst:wiremock:2.1.7")
-		project.dependencies.add("testCompile", "com.toomuchcoding.jsonassert:jsonassert:0.4.7")
+		project.dependencies.add("testCompile", "com.toomuchcoding.jsonassert:jsonassert:0.4.8")
 		project.dependencies.add("testCompile", "org.assertj:assertj-core:2.3.0")
 	}
 

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/test/projects/complex-configuration/pom.xml

@@ -63,7 +63,7 @@
         <dependency>
             <groupId>com.toomuchcoding.jsonassert</groupId>
             <artifactId>jsonassert</artifactId>
-            <version>0.4.7</version>
+            <version>0.4.8</version>
             <scope>test</scope>
         </dependency>
         <dependency>

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/test/projects/plugin-extension/pom.xml

@@ -63,7 +63,7 @@
         <dependency>
             <groupId>com.toomuchcoding.jsonassert</groupId>
             <artifactId>jsonassert</artifactId>
-            <version>0.4.7</version>
+            <version>0.4.8</version>
             <scope>test</scope>
         </dependency>
         <dependency>

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/test/projects/spring-boot-groovy/pom.xml

@@ -64,7 +64,7 @@
         <dependency>
             <groupId>com.toomuchcoding.jsonassert</groupId>
             <artifactId>jsonassert</artifactId>
-            <version>0.4.7</version>
+            <version>0.4.8</version>
             <scope>test</scope>
         </dependency>
         <!-- end::dependencies[] -->

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/test/projects/spring-boot-java/pom.xml

@@ -63,7 +63,7 @@
         <dependency>
             <groupId>com.toomuchcoding.jsonassert</groupId>
             <artifactId>jsonassert</artifactId>
-            <version>0.4.7</version>
+            <version>0.4.8</version>
             <scope>test</scope>
         </dependency>
         <dependency>

spring-cloud-contract-verifier/src/main/groovy/org/springframework/cloud/contract/verifier/dsl/wiremock/WireMockRequestStubStrategy.groovy

@@ -92,7 +92,7 @@ class WireMockRequestStubStrategy extends BaseWireMockStubStrategy {
 			def originalBody = getMatchingStrategyFromBody(request.body)?.clientValue
 			def body = JsonToJsonPathsConverter.removeMatchingJsonPaths(originalBody, request.matchers)
 			JsonPaths values = JsonToJsonPathsConverter.transformToJsonPathWithStubsSideValuesAndNoArraySizeCheck(body)
-			if (values.empty && !request.matchers?.hasMatchers()) {
+			if ((values.empty && !request.matchers?.hasMatchers()) || onlySizeAssertionsArePresent(values)) {
 				requestPattern.withRequestBody(WireMock.equalToJson(JsonOutput.toJson(getMatchingStrategy(request.body.clientValue).clientValue), false, false))
 			} else {
 				values.findAll{ !it.assertsSize() }.each {
@@ -114,12 +114,15 @@ class WireMockRequestStubStrategy extends BaseWireMockStubStrategy {
 			requestPattern.withRequestBody(convertToValuePattern(getMatchingStrategy(request.body.clientValue)))
 		}
 	}
-	
+
+	private boolean onlySizeAssertionsArePresent(JsonPaths values) {
+		return !values.empty && !request.matchers?.hasMatchers() && values.every { it.assertsSize() }
+	}
+
 	private void appendMultipart(RequestPatternBuilder requestPattern) {
 		if (!request.multipart) {
 			return
 		}
-		
 		if (request.multipart.clientValue instanceof Map) {
 			List<StringValuePattern> multipartPatterns = (request.multipart.clientValue as Map).collect {
 				(it.value instanceof NamedProperty

spring-cloud-contract-verifier/src/main/groovy/org/springframework/cloud/contract/verifier/util/DelegatingJsonVerifiable.java

@@ -16,13 +16,13 @@
 
 package org.springframework.cloud.contract.verifier.util;
 
-import static org.apache.commons.lang3.StringEscapeUtils.escapeJava;
-
 import java.util.LinkedList;
 import java.util.regex.Pattern;
 
 import com.toomuchcoding.jsonassert.JsonVerifiable;
 
+import static org.apache.commons.lang3.StringEscapeUtils.escapeJava;
+
 /**
  * Implementation of the {@link MethodBufferingJsonVerifiable} that contains a list
  * of String method commands that need to be executed to assert JSONs.
@@ -187,6 +187,12 @@ class DelegatingJsonVerifiable implements MethodBufferingJsonVerifiable {
 		return readyToCheck;
 	}
 
+	@Override public MethodBufferingJsonVerifiable isEmpty() {
+		DelegatingJsonVerifiable readyToCheck = new FinishedDelegatingJsonVerifiable(this.delegate.isEmpty(), this.methodsBuffer);
+		readyToCheck.methodsBuffer.offer(".isEmpty()");
+		return readyToCheck;
+	}
+
 	@Override
 	public MethodBufferingJsonVerifiable matches(String value) {
 		DelegatingJsonVerifiable readyToCheck = new FinishedDelegatingJsonVerifiable(this.delegate.matches(value), this.methodsBuffer);
@@ -228,7 +234,7 @@ class DelegatingJsonVerifiable implements MethodBufferingJsonVerifiable {
 	@Override
 	public boolean assertsSize() {
 		for (String s : this.methodsBuffer) {
-			if (s.contains(".hasSize(")) {
+			if (s.contains(".hasSize(") || s.contains(".isEmpty()")) {
 				return true;
 			}
 		}

spring-cloud-contract-verifier/src/main/groovy/org/springframework/cloud/contract/verifier/util/JsonToJsonPathsConverter.groovy

@@ -184,7 +184,7 @@ class JsonToJsonPathsConverter {
 				traverseRecursively(Object, valueToAsserter(key.arrayField(), ContentUtils.returnParsedObject(it)),
 						ContentUtils.returnParsedObject(it), closure)
 			}
-		} else if (value instanceof List) {
+		} else if (value instanceof List && !value.empty) {
 			MethodBufferingJsonVerifiable jsonPathVerifiable = createAsserterFromList(key, value)
 			addSizeVerificationForListWithPrimitives(key, closure, value)
 			value.each { def element ->
@@ -192,7 +192,9 @@ class JsonToJsonPathsConverter {
 						ContentUtils.returnParsedObject(element), closure)
 			}
 			return value
-		} else if (key.isIteratingOverArray()) {
+		}  else if (value instanceof List && value.empty) {
+			return runClosure(closure, key, value)
+		}  else if (key.isIteratingOverArray()) {
 			traverseRecursively(Object, key.arrayField().contains(ContentUtils.returnParsedObject(value)),
 					ContentUtils.returnParsedObject(value), closure)
 		}
@@ -292,6 +294,9 @@ class JsonToJsonPathsConverter {
 	}
 
 	private boolean listContainsOnlyPrimitives(List list) {
+		if (list.empty) {
+			return false
+		}
 		return list.every { def element ->
 			[String, Number, Boolean].any {
 				it.isAssignableFrom(element.getClass())
@@ -312,15 +317,22 @@ class JsonToJsonPathsConverter {
 			Object entrykey, value ->
 				def convertedValue = ContentUtils.returnParsedObject(value)
 				[entrykey, traverseRecursively(parentType,
-							convertedValue instanceof List ? listContainsOnlyPrimitives(convertedValue) ?
-									parentKey.arrayField(entrykey) :
-									parentKey.array(entrykey) :
+							convertedValue instanceof List ? list(convertedValue, entrykey, parentKey) :
 							convertedValue instanceof Map ? parentKey.field(new ShouldTraverse(entrykey)) :
 									valueToAsserter(parentKey.field(entrykey), convertedValue)
 							, convertedValue, closureToExecute)]
 		}
 	}
 
+	protected MethodBufferingJsonVerifiable list(List convertedValue, Object entrykey, MethodBufferingJsonVerifiable parentKey) {
+		if (convertedValue.empty) {
+			return parentKey.array(entrykey).isEmpty()
+		}
+		return listContainsOnlyPrimitives(convertedValue) ?
+				parentKey.arrayField(entrykey) :
+				parentKey.array(entrykey)
+	}
+
 	private void traverseRecursivelyForKey(def json, MethodBufferingJsonVerifiable rootKey, Closure closure) {
 		traverseRecursively(Map, rootKey, json, closure)
 	}

spring-cloud-contract-verifier/src/main/groovy/org/springframework/cloud/contract/verifier/util/MethodBufferingJsonVerifiable.java

@@ -59,6 +59,9 @@ public interface MethodBufferingJsonVerifiable
 	@Override
 	MethodBufferingJsonVerifiable isNull();
 
+	@Override
+	MethodBufferingJsonVerifiable isEmpty();
+
 	@Override
 	MethodBufferingJsonVerifiable matches(String value);
 

spring-cloud-contract-verifier/src/test/groovy/org/springframework/cloud/contract/verifier/builder/MockMvcMethodBodyBuilderSpec.groovy

@@ -2123,4 +2123,39 @@ World.'''"""
 			"JaxRsClientSpockMethodRequestProcessingBodyBuilder" | { Contract dsl -> new JaxRsClientSpockMethodRequestProcessingBodyBuilder(dsl, properties) } | { Throwable t, OutputCapture capture -> t.message.contains("Cannot find matching method Script1#executedMethod") }
 			"JaxRsClientJUnitMethodBodyBuilder"                  | { Contract dsl -> new JaxRsClientJUnitMethodBodyBuilder(dsl, properties) }                  | { Throwable t, OutputCapture capture -> t.message.contains("Truncated class file") && capture.toString().contains("path(executedMethod())") }
 	}
+
+	@Issue('#203')
+	def "should create an assertion for an empty list for [#methodBuilderName]"() {
+		given:
+			Contract contractDsl = Contract.make {
+				request {
+					method 'GET'
+					url '/api/v1/xxxx'
+				}
+				response {
+					status 200
+					body([
+							status: '200',
+							list: [],
+							foo: ["bar", "baz"]
+					])
+				}
+			}
+			MethodBodyBuilder builder = methodBuilder(contractDsl)
+			BlockBuilder blockBuilder = new BlockBuilder(" ")
+		and:
+			builder.appendTo(blockBuilder)
+			String test = blockBuilder.toString()
+		when:
+			SyntaxChecker.tryToCompile(methodBuilderName, test)
+		then:
+			test.contains('assertThatJson(parsedJson).array("list").isEmpty()')
+			!test.contains('assertThatJson(parsedJson).array("foo").isEmpty()')
+		where:
+			methodBuilderName                                    | methodBuilder
+			"MockMvcSpockMethodBuilder"                          | { Contract dsl -> new MockMvcSpockMethodRequestProcessingBodyBuilder(dsl, properties) }
+			"MockMvcJUnitMethodBuilder"                          | { Contract dsl -> new MockMvcJUnitMethodBodyBuilder(dsl, properties) }
+			"JaxRsClientSpockMethodRequestProcessingBodyBuilder" | { Contract dsl -> new JaxRsClientSpockMethodRequestProcessingBodyBuilder(dsl, properties) }
+			"JaxRsClientJUnitMethodBodyBuilder"                  | { Contract dsl -> new JaxRsClientJUnitMethodBodyBuilder(dsl, properties) }
+	}
 }