Should not fail when matchers don't have dots

fixes gh-894

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

@@ -154,7 +154,11 @@ class JsonToJsonPathsConverter {
 					removeTrailingContainers(pathToDelete, context)
 		}
 		else {
-			String lastParent = matcherPath.substring(0, matcherPath.lastIndexOf("."))
+			int lastIndexOfDot = matcherPath.lastIndexOf(".")
+			if (lastIndexOfDot == -1) {
+				return false
+			}
+			String lastParent = matcherPath.substring(0, lastIndexOfDot)
 			def lastParentObject = context.read(lastParent)
 			if (isIterable(lastParentObject)
 					&&
@@ -229,9 +233,9 @@ class JsonToJsonPathsConverter {
 			return path
 		}
 		int lastIndexOfDot = lastIndexOfDot(path)
-		String toLastDot = path.substring(0, lastIndexOfDot)
 		String fromLastDot = path.substring(lastIndexOfDot + 1)
-		String propertyName = "@.${fromLastDot}"
+		String toLastDot = lastIndexOfDot == -1 ? '$' : path.substring(0, lastIndexOfDot)
+		String propertyName = lastIndexOfDot == -1 ? '@' : "@.${fromLastDot}"
 		String comparison = createComparison(propertyName, bodyMatcher, value, body)
 		return "${toLastDot}[?(${comparison})]"
 	}

spring-cloud-contract-verifier/src/test/groovy/org/springframework/cloud/contract/verifier/dsl/wiremock/WireMockGroovyDslSpec.groovy

@@ -2669,6 +2669,32 @@ class WireMockGroovyDslSpec extends Specification implements WireMockStubVerifie
 
 	}
 
+	@Issue("#894")
+	def "should not fail when matchers don't have dots"() {
+		given:
+			Contract contractDsl =  Contract.make {
+				request {
+					method 'POST'
+					url "/example"
+					body([ "123", "234"])
+					bodyMatchers {
+						jsonPath('$[*]', byRegex(nonEmpty()))
+					}
+				}
+				response {
+					status 201
+				}
+			}
+		when:
+			String wireMockStub = new WireMockStubStrategy("Test",
+					new ContractMetadata(null, false, 0, null, contractDsl), contractDsl)
+					.toWireMockClientStub()
+
+		then:
+			stubMappingIsValidWireMockStub(wireMockStub)
+
+	}
+
 	WireMockConfiguration config() {
 		return new WireMockConfiguration().extensions(responseTemplateTransformer())
 	}