Add a SlsVersionMatcher comparator (#3)

* Add a SlsVersionMatcher comparator * More tests
palantir · Jun 18, 2018 · 77d0655 · 77d0655
1 parent fef350d
commit 77d0655
Show file tree

Hide file tree

Showing 2 changed files with 26 additions and 0 deletions.
diff --git a/sls-versions/src/main/java/com/palantir/sls/versions/SlsVersionMatcher.java b/sls-versions/src/main/java/com/palantir/sls/versions/SlsVersionMatcher.java
@@ -24,6 +24,7 @@
 import com.palantir.immutables.style.ImmutablesStyle;
 import com.palantir.logsafe.SafeArg;
 import com.palantir.logsafe.UnsafeArg;
+import java.util.Comparator;
 import java.util.Optional;
 import java.util.OptionalInt;
 import java.util.regex.Matcher;
@@ -43,6 +44,14 @@ public abstract class SlsVersionMatcher {
     private static final Logger log = LoggerFactory.getLogger(SlsVersionMatcher.class);
     private static final Pattern PATTERN = Pattern.compile("^(([0-9]+|x))\\.(([0-9]+|x))\\.(([0-9]+|x))$");
 
+    private static final Comparator<OptionalInt> EMPTY_IS_GREATER =
+            Comparator.comparingInt(num -> num.isPresent() ? num.getAsInt() : Integer.MAX_VALUE);
+
+    public static final Comparator<SlsVersionMatcher> MATCHER_COMPARATOR = Comparator
+            .comparing(SlsVersionMatcher::getMajorVersionNumber, EMPTY_IS_GREATER)
+            .thenComparing(SlsVersionMatcher::getMinorVersionNumber, EMPTY_IS_GREATER)
+            .thenComparing(SlsVersionMatcher::getPatchVersionNumber, EMPTY_IS_GREATER);
+
     @Value.Auxiliary
     public abstract String getValue();
     public abstract OptionalInt getMajorVersionNumber();

diff --git a/sls-versions/src/test/java/com/palantir/sls/versions/SlsVersionMatcherTest.java b/sls-versions/src/test/java/com/palantir/sls/versions/SlsVersionMatcherTest.java
@@ -109,6 +109,23 @@ public void testCompare() {
         assertThat(matcher("1.2.x").compare(version("1.2.3-rc1"))).isZero();
     }
 
+    @Test
+    public void testMatcherComparator_xTrumpsNumber() {
+        assertMatcherOrder(SlsVersionMatcher.valueOf("2.6.x"), SlsVersionMatcher.valueOf("2.x.x"));
+        assertMatcherOrder(SlsVersionMatcher.valueOf("2.6.5"), SlsVersionMatcher.valueOf("2.6.x"));
+    }
+
+    @Test
+    public void testMatcherComparator_comparesNumbers() {
+        assertMatcherOrder(SlsVersionMatcher.valueOf("2.6.x"), SlsVersionMatcher.valueOf("2.7.x"));
+        assertMatcherOrder(SlsVersionMatcher.valueOf("2.6.5"), SlsVersionMatcher.valueOf("2.6.6"));
+    }
+
+    private static void assertMatcherOrder(SlsVersionMatcher smaller, SlsVersionMatcher larger) {
+        assertThat(SlsVersionMatcher.MATCHER_COMPARATOR.compare(smaller, larger)).isLessThan(0);
+        assertThat(SlsVersionMatcher.MATCHER_COMPARATOR.compare(larger, smaller)).isGreaterThan(0);
+    }
+
     private static SlsVersionMatcher matcher(String value) {
         return SlsVersionMatcher.valueOf(value);
     }