Fix version logic when bumping major version (#38595)

When we are preparing to release a major version the rules around
"unreleased" versions and branches get a bit more complex.

This change implements the following rules:

- If the tip version on the previous major is a .0 (e.g. 6.7.0) then
  the tip of the minor before that (e.g. 6.6.1) must be unreleased.
  (This is because 6.7.0 would be "staged" in preparation for release,
  but 6.6.1 would be open for bug fixes on the release 6.6.x line)
  (in VersionCollection & VersionUtils)

- The "major.x" branch (if it exists) will always point to the latest
  minor in that series. Anything that is not the latest minor, must
  therefore be on a the "major.minor" branch
  For example, if v7.1.0 exists then the "7.x" branch must be 7.1.0,
  and 7.0.0 must be on the "7.0" branch
  (in VersionCollection)

- Special logic so that the 7.0.0 build knows that we do not plan
   to have any 6.x releases after the 6.7 series
 
Backport of: #38593 
Partial Backport of: #38513

Co-authored-by: Jason Tedor <[email protected]>

Author: tvernum

buildSrc/src/main/java/org/elasticsearch/gradle/VersionCollection.java

@@ -171,30 +171,38 @@ public UnreleasedVersionInfo unreleasedInfo(Version version) {
     }
 
     public void forPreviousUnreleased(Consumer<UnreleasedVersionInfo> consumer) {
-        getUnreleased().stream()
+        List<UnreleasedVersionInfo> collect = getUnreleased().stream()
             .filter(version -> version.equals(currentVersion) == false)
-            .forEach(version -> consumer.accept(
-                new UnreleasedVersionInfo(
+            .map(version -> new UnreleasedVersionInfo(
                     version,
                     getBranchFor(version),
                     getGradleProjectNameFor(version)
                 )
-            ));
+            )
+            .collect(Collectors.toList());
+
+        collect.forEach(uvi -> consumer.accept(uvi));
     }
 
     private String getGradleProjectNameFor(Version version) {
         if (version.equals(currentVersion)) {
             throw new IllegalArgumentException("The Gradle project to build " + version + " is the current build.");
         }
+
         Map<Integer, List<Version>> releasedMajorGroupedByMinor = getReleasedMajorGroupedByMinor();
 
         if (version.getRevision() == 0) {
-            if (releasedMajorGroupedByMinor
-                .get(releasedMajorGroupedByMinor.keySet().stream().max(Integer::compareTo).orElse(0))
-                .contains(version)) {
-                return "minor";
+            List<Version> unreleasedStagedOrMinor = getUnreleased().stream()
+                .filter(v -> v.getRevision() == 0)
+                .collect(Collectors.toList());
+            if (unreleasedStagedOrMinor.size() > 2) {
+                if (unreleasedStagedOrMinor.get(unreleasedStagedOrMinor.size() - 2).equals(version)) {
+                    return "minor";
+                } else{
+                    return "staged";
+                }
             } else {
-                return "staged";
+                return "minor";
             }
         } else {
             if (releasedMajorGroupedByMinor
@@ -210,7 +218,14 @@ private String getGradleProjectNameFor(Version version) {
     private String getBranchFor(Version version) {
         switch (getGradleProjectNameFor(version)) {
             case "minor":
-                return version.getMajor() + ".x";
+                // The .x branch will always point to the latest minor (for that major), so a "minor" project will be on the .x branch
+                //  unless there is more recent (higher) minor.
+                final Version latestInMajor = getLatestVersionByKey(groupByMajor, version.getMajor());
+                if (latestInMajor.getMinor() == version.getMinor() && isFinalMinor(version) == false) {
+                    return version.getMajor() + ".x";
+                } else {
+                    return version.getMajor() + "." + version.getMinor();
+                }
             case "staged":
             case "maintenance":
             case "bugfix":
@@ -220,13 +235,30 @@ private String getBranchFor(Version version) {
         }
     }
 
+    /**
+     * There is no way to infer that 6.7 is the final minor release in the 6.x series until we add a 7.0.1 or 7.1.0 version.
+     * Based on the available versions (7.0.0, 6.7.0, 6.6.1, 6.6.0) the logical conclusion is that 7.0.0 is "master" and 6.7.0 is "6.x"
+     * This method force 6.7.0 to be recognised as being on the "6.7" branch
+     */
+    private boolean isFinalMinor(Version version) {
+        return (version.getMajor() == 6 && version.getMinor() == 7);
+    }
+
     public List<Version> getUnreleased() {
         List<Version> unreleased = new ArrayList<>();
         // The current version is being worked, is always unreleased
         unreleased.add(currentVersion);
 
         // the tip of the previous major is unreleased for sure, be it a minor or a bugfix
-        unreleased.add(getLatestVersionByKey(this.groupByMajor, currentVersion.getMajor() - 1));
+        final Version latestOfPreviousMajor = getLatestVersionByKey(this.groupByMajor, currentVersion.getMajor() - 1);
+        unreleased.add(latestOfPreviousMajor);
+        if (latestOfPreviousMajor.getRevision() == 0) {
+            // if the previous major is a x.y.0 release, then the tip of the minor before that (y-1) is also unreleased
+            final Version previousMinor = getLatestInMinor(latestOfPreviousMajor.getMajor(), latestOfPreviousMajor.getMinor() - 1);
+            if (previousMinor != null) {
+                unreleased.add(previousMinor);
+            }
+        }
 
         final Map<Integer, List<Version>> groupByMinor = getReleasedMajorGroupedByMinor();
         int greatestMinor = groupByMinor.keySet().stream().max(Integer::compareTo).orElse(0);
@@ -239,8 +271,10 @@ public List<Version> getUnreleased() {
             unreleased.add(getLatestVersionByKey(groupByMinor, greatestMinor - 1));
             if (groupByMinor.getOrDefault(greatestMinor - 1, emptyList()).size() == 1) {
                 // we found that the previous minor is staged but not yet released
-                // in this case, the minor before that has a bugfix
-                unreleased.add(getLatestVersionByKey(groupByMinor, greatestMinor - 2));
+                // in this case, the minor before that has a bugfix, should there be such a minor
+                if (greatestMinor >= 2) {
+                    unreleased.add(getLatestVersionByKey(groupByMinor, greatestMinor - 2));
+                }
             }
         }
 
@@ -252,6 +286,13 @@ public List<Version> getUnreleased() {
         );
     }
 
+    private Version getLatestInMinor(int major, int minor) {
+        return groupByMajor.get(major).stream()
+            .filter(v -> v.getMinor() == minor)
+            .max(Version::compareTo)
+            .orElse(null);
+    }
+
     private Version getLatestVersionByKey(Map<Integer, List<Version>> groupByMajor, int key) {
         return groupByMajor.getOrDefault(key, emptyList()).stream()
             .max(Version::compareTo)

buildSrc/src/test/java/org/elasticsearch/gradle/VersionCollectionTests.java

@@ -81,6 +81,12 @@ public class VersionCollectionTests extends GradleUnitTestCase {
             "6_0_0", "6_0_1", "6_1_0", "6_1_1", "6_1_2", "6_1_3", "6_1_4", "6_2_0", "6_2_1", "6_2_2", "6_2_3",
             "6_2_4", "6_3_0", "6_3_1", "6_3_2", "6_4_0", "6_4_1", "6_4_2"
         ));
+        sampleVersions.put("7.0.0", asList(
+            "7_0_0", "6_7_0", "6_6_2", "6_6_1", "6_6_0"
+        ));
+        sampleVersions.put("7.1.0", asList(
+            "7_1_0", "7_0_0", "6_7_0", "6_6_1", "6_6_0"
+        ));
     }
 
     @Test(expected = IllegalArgumentException.class)
@@ -145,6 +151,11 @@ public void testWireCompatible() {
             singletonList("7.3.0"),
             getVersionCollection("8.0.0").getWireCompatible()
         );
+        assertVersionsEquals(
+            asList("6.7.0", "7.0.0"),
+            getVersionCollection("7.1.0").getWireCompatible()
+        );
+
     }
 
     public void testWireCompatibleUnreleased() {
@@ -171,6 +182,10 @@ public void testWireCompatibleUnreleased() {
             singletonList("7.3.0"),
             getVersionCollection("8.0.0").getUnreleasedWireCompatible()
         );
+        assertVersionsEquals(
+            asList("6.7.0", "7.0.0"),
+            getVersionCollection("7.1.0").getWireCompatible()
+        );
     }
 
     public void testIndexCompatible() {
@@ -270,6 +285,14 @@ public void testGetUnreleased() {
             asList("7.1.1", "7.2.0", "7.3.0", "8.0.0"),
             getVersionCollection("8.0.0").getUnreleased()
         );
+        assertVersionsEquals(
+            asList("6.6.1", "6.7.0", "7.0.0", "7.1.0"),
+            getVersionCollection("7.1.0").getUnreleased()
+        );
+        assertVersionsEquals(
+            asList("6.6.2", "6.7.0", "7.0.0"),
+            getVersionCollection("7.0.0").getUnreleased()
+        );
     }
 
     public void testGetBranch() {
@@ -293,6 +316,14 @@ public void testGetBranch() {
             asList("7.1", "7.2", "7.x"),
             getVersionCollection("8.0.0")
         );
+        assertUnreleasedBranchNames(
+            asList("6.6", "6.7", "7.0"),
+            getVersionCollection("7.1.0")
+        );
+        assertUnreleasedBranchNames(
+            asList("6.6", "6.7"),
+            getVersionCollection("7.0.0")
+        );
     }
 
     public void testGetGradleProjectName() {
@@ -309,13 +340,17 @@ public void testGetGradleProjectName() {
             getVersionCollection("6.4.2")
         );
         assertUnreleasedGradleProjectNames(
-            asList("maintenance", "bugfix", "staged"),
+            asList("maintenance", "bugfix", "minor"),
             getVersionCollection("6.6.0")
         );
         assertUnreleasedGradleProjectNames(
             asList("bugfix", "staged", "minor"),
             getVersionCollection("8.0.0")
         );
+        assertUnreleasedGradleProjectNames(
+            asList("maintenance", "staged", "minor"),
+            getVersionCollection("7.1.0")
+        );
     }
 
     public void testCompareToAuthoritative() {

test/framework/src/main/java/org/elasticsearch/test/VersionUtils.java

@@ -43,7 +43,7 @@ public class VersionUtils {
      * rules here match up with the rules in gradle then this should
      * produce sensible results.
      * @return a tuple containing versions with backwards compatibility
-     * guarantees in v1 and versions without the guranteees in v2
+     * guarantees in v1 and versions without the guarantees in v2
      */
     static Tuple<List<Version>, List<Version>> resolveReleasedVersions(Version current, Class<?> versionClass) {
         // group versions into major version
@@ -52,7 +52,7 @@ static Tuple<List<Version>, List<Version>> resolveReleasedVersions(Version curre
         // this breaks b/c 5.x is still in version list but master doesn't care about it!
         //assert majorVersions.size() == 2;
         // TODO: remove oldVersions, we should only ever have 2 majors in Version
-        List<Version> oldVersions = majorVersions.getOrDefault((int)current.major - 2, Collections.emptyList());
+        List<List<Version>> oldVersions = splitByMinor(majorVersions.getOrDefault((int)current.major - 2, Collections.emptyList()));
         List<List<Version>> previousMajor = splitByMinor(majorVersions.get((int)current.major - 1));
         List<List<Version>> currentMajor = splitByMinor(majorVersions.get((int)current.major));
 
@@ -67,7 +67,11 @@ static Tuple<List<Version>, List<Version>> resolveReleasedVersions(Version curre
             // on a stable or release branch, ie N.x
             stableVersions = currentMajor;
             // remove the next maintenance bugfix
-            moveLastToUnreleased(previousMajor, unreleasedVersions);
+            final Version prevMajorLastMinor = moveLastToUnreleased(previousMajor, unreleasedVersions);
+            if (prevMajorLastMinor.revision == 0 && previousMajor.isEmpty() == false) {
+                // The latest minor in the previous major is a ".0" release, so there must be an unreleased bugfix for the minor before that
+                moveLastToUnreleased(previousMajor, unreleasedVersions);
+            }
         }
 
         // remove next minor
@@ -78,12 +82,21 @@ static Tuple<List<Version>, List<Version>> resolveReleasedVersions(Version curre
                 moveLastToUnreleased(stableVersions, unreleasedVersions);
             }
             // remove the next bugfix
-            moveLastToUnreleased(stableVersions, unreleasedVersions);
+            if (stableVersions.isEmpty() == false) {
+                moveLastToUnreleased(stableVersions, unreleasedVersions);
+            }
         }
 
-        List<Version> releasedVersions = Stream.concat(oldVersions.stream(),
-            Stream.concat(previousMajor.stream(), currentMajor.stream()).flatMap(List::stream))
-            .collect(Collectors.toList());
+        // If none of the previous major was released, then the last minor and bugfix of the old version was not released either.
+        if (previousMajor.isEmpty()) {
+            assert currentMajor.isEmpty() : currentMajor;
+            // minor of the old version is being staged
+            moveLastToUnreleased(oldVersions, unreleasedVersions);
+            // bugix of the old version is also being staged
+            moveLastToUnreleased(oldVersions, unreleasedVersions);
+        }
+        List<Version> releasedVersions = Stream.of(oldVersions, previousMajor, currentMajor)
+            .flatMap(List::stream).flatMap(List::stream).collect(Collectors.toList());
         Collections.sort(unreleasedVersions); // we add unreleased out of order, so need to sort here
         return new Tuple<>(Collections.unmodifiableList(releasedVersions), Collections.unmodifiableList(unreleasedVersions));
     }