Merge commits tunable (#3496)

fixes #3367

Author: Vladimir Kotal

opengrok-indexer/src/main/java/org/opengrok/indexer/configuration/Configuration.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2007, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2017, 2020, Chris Fraire <cfraire@me.com>.
  * Portions Copyright (c) 2020, Aleksandr Kirillov <alexkirillovsamara@gmail.com>.
  */
@@ -232,6 +232,8 @@ public final class Configuration {
      */
     private boolean handleHistoryOfRenamedFiles;
 
+    private boolean mergeCommitsEnabled;
+
     public static final double defaultRamBufferSize = 16;
 
     /**
@@ -541,6 +543,7 @@ public Configuration() {
         //mandoc is default(String)
         setMaxSearchThreadCount(2 * Runtime.getRuntime().availableProcessors());
         setMaxRevisionThreadCount(Runtime.getRuntime().availableProcessors());
+        setMergeCommitsEnabled(true);
         setMessageLimit(500);
         setNavigateWindowEnabled(false);
         setNestingMaximum(1);
@@ -831,6 +834,14 @@ public void setHandleHistoryOfRenamedFiles(boolean enable) {
         this.handleHistoryOfRenamedFiles = enable;
     }
 
+    public void setMergeCommitsEnabled(boolean flag) {
+        this.mergeCommitsEnabled = flag;
+    }
+
+    public boolean isMergeCommitsEnabled() {
+        return mergeCommitsEnabled;
+    }
+
     public boolean isNavigateWindowEnabled() {
         return navigateWindowEnabled;
     }

opengrok-indexer/src/main/java/org/opengrok/indexer/configuration/Project.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2006, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2018, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.configuration;
@@ -83,6 +83,11 @@ public class Project implements Comparable<Project>, Nameable, Serializable {
      */
     private Boolean historyEnabled = null;
 
+    /**
+     * This flag enables/disables per project merge commits.
+     */
+    private Boolean mergeCommitsEnabled = null;
+
     /**
      * This marks the project as (not)ready before initial index is done. this
      * is to avoid all/multi-project searches referencing this project from
@@ -237,6 +242,13 @@ public boolean isHandleRenamedFiles() {
         return handleRenamedFiles != null && handleRenamedFiles;
     }
 
+    /**
+     * @return true if merge commits are enabled.
+     */
+    public boolean isMergeCommitsEnabled() {
+        return mergeCommitsEnabled != null && mergeCommitsEnabled;
+    }
+
     /**
      * @param flag true if project should handle renamed files, false otherwise.
      */
@@ -258,6 +270,13 @@ public void setHistoryEnabled(boolean flag) {
         this.historyEnabled = flag;
     }
 
+    /**
+     * @param flag true if project's repositories should deal with merge commits.
+     */
+    public void setMergeCommitsEnabled(boolean flag) {
+        this.mergeCommitsEnabled = flag;
+    }
+
     /**
      * Return groups where this project belongs.
      *
@@ -322,6 +341,11 @@ public final void completeWithDefaults() {
         if (navigateWindowEnabled == null) {
             setNavigateWindowEnabled(env.isNavigateWindowEnabled());
         }
+
+        // Allow project to override global setting of merge commits.
+        if (mergeCommitsEnabled == null) {
+            setMergeCommitsEnabled(env.isMergeCommitsEnabled());
+        }
     }
 
     /**

opengrok-indexer/src/main/java/org/opengrok/indexer/configuration/RuntimeEnvironment.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2006, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2017, 2020, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.configuration;
@@ -1251,6 +1251,14 @@ public boolean isHandleHistoryOfRenamedFiles() {
         return syncReadConfiguration(Configuration::isHandleHistoryOfRenamedFiles);
     }
 
+    public void setMergeCommitsEnabled(boolean flag) {
+        syncWriteConfiguration(flag, Configuration::setMergeCommitsEnabled);
+    }
+
+    public boolean isMergeCommitsEnabled() {
+        return syncReadConfiguration(Configuration::isMergeCommitsEnabled);
+    }
+
     public void setNavigateWindowEnabled(boolean navigateWindowEnabled) {
         syncWriteConfiguration(navigateWindowEnabled, Configuration::setNavigateWindowEnabled);
     }

opengrok-indexer/src/main/java/org/opengrok/indexer/history/GitRepository.java

@@ -171,7 +171,9 @@ Executor getHistoryLogExecutor(final File file, String sinceRevision)
         cmd.add("--name-only");
         cmd.add("--pretty=fuller");
         cmd.add(GIT_DATE_OPT);
-        cmd.add("-m");
+        if (isMergeCommitsEnabled()) {
+            cmd.add("-m");
+        }
 
         if (file.isFile() && isHandleRenamedFiles()) {
             cmd.add("--follow");

opengrok-indexer/src/main/java/org/opengrok/indexer/history/Repository.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2017, 2020, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.history;

opengrok-indexer/src/main/java/org/opengrok/indexer/history/RepositoryInfo.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2017, 2019, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.history;
@@ -77,6 +77,8 @@ public class RepositoryInfo implements Serializable {
     private boolean handleRenamedFiles;
     @DTOElement
     private boolean historyEnabled;
+    @DTOElement
+    private boolean mergeCommitsEnabled;
 
     /**
      * Empty constructor to support serialization.
@@ -110,6 +112,20 @@ public void setHandleRenamedFiles(boolean flag) {
         this.handleRenamedFiles = flag;
     }
 
+    /**
+     * @return true if the repository handles merge commits.
+     */
+    public boolean isMergeCommitsEnabled() {
+        return this.mergeCommitsEnabled;
+    }
+
+    /**
+     * @param flag true if the repository should handle merge commits, false otherwise.
+     */
+    public void setMergeCommitsEnabled(boolean flag) {
+        this.mergeCommitsEnabled = flag;
+    }
+
     /**
      * @return true if the repository should have history cache.
      */
@@ -293,11 +309,13 @@ public void fillFromProject() {
         if (proj != null) {
             setHistoryEnabled(proj.isHistoryEnabled());
             setHandleRenamedFiles(proj.isHandleRenamedFiles());
+            setMergeCommitsEnabled(proj.isMergeCommitsEnabled());
         } else {
             RuntimeEnvironment env = RuntimeEnvironment.getInstance();
 
             setHistoryEnabled(env.isHistoryEnabled());
             setHandleRenamedFiles(env.isHandleHistoryOfRenamedFiles());
+            setMergeCommitsEnabled(env.isMergeCommitsEnabled());
         }
     }
 

opengrok-indexer/src/test/java/org/opengrok/indexer/history/GitRepositoryOctopusTest.java

@@ -18,7 +18,7 @@
  */
 
 /*
- * Copyright (c) 2008, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2021, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright (c) 2019, 2020, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.history;
@@ -34,6 +34,7 @@
 import org.opengrok.indexer.condition.ConditionalRun;
 import org.opengrok.indexer.condition.ConditionalRunRule;
 import org.opengrok.indexer.condition.RepositoryInstalled;
+import org.opengrok.indexer.configuration.RuntimeEnvironment;
 import org.opengrok.indexer.util.TestRepository;
 import org.opengrok.indexer.web.Util;
 
@@ -59,6 +60,7 @@ public static void setUpClass() throws Exception {
         repository = new TestRepository();
         repository.create(GitRepositoryOctopusTest.class.getResourceAsStream(
                 "/history/git-octopus.zip"));
+        RuntimeEnvironment.getInstance().setMergeCommitsEnabled(true);
     }
 
     @AfterClass