Allow fields' values to be empty lists during searching for patterns

accurest-core/src/main/groovy/io/codearte/accurest/dsl/WireMockRequestStubStrategy.groovy

@@ -139,7 +139,7 @@ class WireMockRequestStubStrategy extends BaseWireMockStubStrategy {
 	}
 
 	private boolean containsPattern(Collection collection) {
-		return collection.collect(this.&containsPattern).inject { a, b -> a || b }
+		return collection.collect(this.&containsPattern).inject('') { a, b -> a || b }
 	}
 
 	private boolean containsPattern(Object[] objects) {

accurest-core/src/test/groovy/io/codearte/accurest/dsl/WireMockGroovyDslSpec.groovy

@@ -1192,4 +1192,39 @@ class WireMockGroovyDslSpec extends WireMockSpec {
 	String toWireMockClientJsonStub(groovyDsl) {
 		new WireMockStubStrategy(groovyDsl).toWireMockClientStub()
 	}
+
+	def 'should generate stub with empty list as a value of a field'() {
+		given:
+			GroovyDsl groovyDsl = GroovyDsl.make {
+				request {
+					method('POST')
+					body(
+						values: []
+					)
+				}
+				response {
+					status 200
+				}
+			}
+		when:
+			String wireMockStub = new WireMockStubStrategy(groovyDsl).toWireMockClientStub()
+		then:
+			new JsonSlurper().parseText(wireMockStub) == new JsonSlurper().parseText('''
+				{
+					"request": {
+						"method": "POST",
+						"bodyPatterns": [
+							{
+								"equalToJson": "{\\"values\\":[]}"
+							}
+						]
+					},
+					"response": {
+						"status": 200
+					}
+				}
+			''')
+		and:
+			stubMappingIsValidWireMockStub(wireMockStub)
+	}
 }