Added a guard to point to a missing type in YAML

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/main/java/org/springframework/cloud/contract/maven/verifier/BaseClassMapping.java

@@ -50,4 +50,9 @@ public class BaseClassMapping {
 		result = 31 * result + (this.baseClassFQN != null ? this.baseClassFQN.hashCode() : 0);
 		return result;
 	}
+
+	@Override public String toString() {
+		return "BaseClassMapping{" + "contractPackageRegex='" + this.contractPackageRegex
+				+ '\'' + ", baseClassFQN='" + this.baseClassFQN + '\'' + '}';
+	}
 }

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/main/java/org/springframework/cloud/contract/maven/verifier/GenerateTestsMojo.java

@@ -248,7 +248,8 @@ public class GenerateTestsMojo extends AbstractMojo {
 							+ " added.");
 			getLog().info("Using [" + config.getBaseClassForTests()
 					+ "] as base class for test classes, [" + config.getBasePackageForTests() + "] as base "
-					+ "package for tests, [" + config.getPackageWithBaseClasses() + "] as package with base classes");
+					+ "package for tests, [" + config.getPackageWithBaseClasses() + "] as package with "
+					+ "base classes, base class mappings " + this.baseClassMappings);
 		}
 		try {
 			TestGenerator generator = new TestGenerator(config);

spring-cloud-contract-verifier/src/main/groovy/org/springframework/cloud/contract/verifier/converter/YamlContractConverter.groovy

@@ -293,6 +293,8 @@ class YamlContractConverter implements ContractConverter<List<YamlContract>> {
 										case StubMatcherType.by_equality:
 											value = byEquality()
 											break
+										default:
+											throw new UnsupportedOperationException("The type [" + matcher.type + "] is unsupported. Hint: If you're using <predefined> remember to pass <type: by_regex>")
 									}
 									jsonPath(matcher.path, value)
 								}
@@ -349,6 +351,8 @@ class YamlContractConverter implements ContractConverter<List<YamlContract>> {
 											case TestMatcherType.by_null:
 												value = byNull()
 												break
+											default:
+												throw new UnsupportedOperationException("The type [" + testMatcher.type + "] is unsupported. Hint: If you're using <predefined> remember to pass <type: by_regex>")
 										}
 										jsonPath(testMatcher.path, value)
 									}