fixed version scheme in WatcherVersion

Original commit: elastic/x-pack-elasticsearch@1007cd71a3

src/main/java/org/elasticsearch/watcher/WatcherVersion.java

@@ -69,7 +69,7 @@ public class WatcherVersion implements Serializable {
             return WatcherVersion.CURRENT;
         }
 
-        String[] parts = version.split("\\.");
+        String[] parts = version.split("\\.|\\-");
         if (parts.length < 3 || parts.length > 4) {
             throw new IllegalArgumentException("the version needs to contain major, minor and revision, and optionally the build");
         }
@@ -179,9 +179,9 @@ public class WatcherVersion implements Serializable {
         StringBuilder sb = new StringBuilder();
         sb.append(major).append('.').append(minor).append('.').append(revision);
         if (build < 50) {
-            sb.append(".Beta").append(build);
+            sb.append("-beta").append(build);
         } else if (build < 99) {
-            sb.append(".RC").append(build - 50);
+            sb.append("-rc").append(build - 50);
         }
         return sb.toString();
     }

src/test/java/org/elasticsearch/watcher/WatcherVersionTests.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.watcher;
+
+import com.carrotsearch.randomizedtesting.annotations.Repeat;
+import org.elasticsearch.test.ElasticsearchTestCase;
+import org.junit.Test;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
+
+/**
+ *
+ */
+public class WatcherVersionTests extends ElasticsearchTestCase {
+
+    @Test
+    @Repeat(iterations = 100)
+    public void testStrings() throws Exception {
+        boolean beta = randomBoolean();
+        int buildNumber = beta ? randomIntBetween(0, 49) : randomIntBetween(0, 48);
+        int major = randomIntBetween(0, 20);
+        int minor = randomIntBetween(0, 20);
+        int revision = randomIntBetween(0, 20);
+
+        String build = buildNumber == 0 ? "" :
+                beta ? "-beta" + buildNumber : "-rc" + buildNumber;
+
+
+        String versionName = new StringBuilder()
+                .append(major)
+                .append(".").append(minor)
+                .append(".").append(revision)
+                .append(build).toString();
+        WatcherVersion version = WatcherVersion.fromString(versionName);
+
+        logger.info("version: {}", versionName);
+
+        assertThat(version.major, is((byte) major));
+        assertThat(version.minor, is((byte) minor));
+        assertThat(version.revision, is((byte) revision));
+        if (buildNumber == 0) {
+            assertThat(version.build, is((byte) 99));
+        } else if (beta) {
+            assertThat(version.build, is((byte) buildNumber));
+        } else {
+            assertThat(version.build, is((byte) (buildNumber + 50)));
+        }
+
+        assertThat(version.number(), equalTo(versionName));
+    }
+}