Fixed the way regex entries are generated for message bodies; fixes gh-858

spring-cloud-contract-spec/src/main/groovy/org/springframework/cloud/contract/spec/internal/OptionalProperty.groovy

@@ -20,6 +20,7 @@ import java.util.regex.Pattern
 
 import groovy.transform.CompileStatic
 import groovy.transform.ToString
+import repackaged.nl.flotsam.xeger.Xeger
 
 /**
  * Represents a property that may or may not be there
@@ -28,7 +29,7 @@ import groovy.transform.ToString
  */
 @CompileStatic
 @ToString(includePackage = false, includeNames = true)
-class OptionalProperty implements Serializable {
+class OptionalProperty implements Serializable, CanBeDynamic {
 	final Object value
 
 	OptionalProperty(Object value) {
@@ -56,4 +57,9 @@ class OptionalProperty implements Serializable {
 	String toString() {
 		return optionalPattern()
 	}
+
+	@Override
+	Object generateConcreteValue() {
+		return new Xeger(optionalPattern()).generate()
+	}
 }

spring-cloud-contract-spec/src/main/groovy/org/springframework/cloud/contract/spec/internal/RegexProperty.groovy

@@ -33,7 +33,7 @@ import repackaged.nl.flotsam.xeger.Xeger
 @TypeChecked
 @EqualsAndHashCode
 @ToString(includePackage = false, includeNames = true)
-class RegexProperty extends DslProperty {
+class RegexProperty extends DslProperty implements CanBeDynamic {
 	final Pattern pattern
 	private final Class clazz
 
@@ -169,4 +169,9 @@ class RegexProperty extends DslProperty {
 	String toString() {
 		return this.pattern()
 	}
+
+	@Override
+	Object generateConcreteValue() {
+		return generate()
+	}
 }