Add feature to ignore git commits by id

docs/index.md

@@ -73,6 +73,7 @@ Basically, when you are developing a project either in open source or in a compa
 * [@stain](https://github.com/stain)
 * [@vromero](https://github.com/vromero)
 * [@yoosiba](https://github.com/yoosiba)
+* [@philippn](https://github.com/philippn)
 
 Please let me know if your name is missing!
 

license-maven-plugin-git/README.md

@@ -20,6 +20,8 @@ Which properties is license-maven-plugin-git adding?
 
 The full git history for a file is required for accurate determination of the first commit (for the creation author name/email, creation year, or existence years). The plugin will warn if it detects a shallow git repository. If you are certain your shallow depth will still permit determination of these values you may suppress the warning by setting the parameter `license.warnIfShallow` to false.
 
+It is possible to filter out specific commits by adding one or more (comma-separated) SHA-1 hashes to the property `license.git.commitsToIgnore`. This property will only affect the computation of the last change year, not of the creation year.
+
 If you are using properties requiring the year of the last commit of a file but not using the "creation" properties requiring the first commit, you can improve performance by limiting the git history for each file using the property `license.git.maxCommitsLookup`. A value of 1 would provide the best performance but could be impacted if the last commit year is earlier than the year of previous commits.
 
 How to use license-maven-plugin-git

license-maven-plugin-git/src/main/java/com/mycila/maven/plugin/license/git/GitLookup.java

@@ -21,16 +21,21 @@
 import java.io.UncheckedIOException;
 import java.util.Arrays;
 import java.util.Calendar;
+import java.util.Collections;
 import java.util.Date;
 import java.util.Iterator;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Set;
 import java.util.TimeZone;
+import java.util.stream.Collectors;
+
 import org.eclipse.jgit.api.Git;
 import org.eclipse.jgit.api.Status;
 import org.eclipse.jgit.api.errors.GitAPIException;
 import org.eclipse.jgit.diff.DiffConfig;
 import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.FollowFilter;
@@ -57,6 +62,7 @@ public class GitLookup implements Closeable {
   private static final String COPYRIGHT_LAST_YEAR_MAX_COMMITS_LOOKUP_KEY = "license.git.copyrightLastYearMaxCommitsLookup";
   public static final String COPYRIGHT_LAST_YEAR_SOURCE_KEY = "license.git.copyrightLastYearSource";
   public static final String COPYRIGHT_LAST_YEAR_TIME_ZONE_KEY = "license.git.copyrightLastYearTimeZone";
+  public static final String COMMITS_TO_IGNORE_KEY = "license.git.commitsToIgnore";
 
   public enum DateSource {
     AUTHOR, COMMITER
@@ -68,6 +74,7 @@ public enum DateSource {
   private final Repository repository;
   private final TimeZone timeZone;
   private final boolean shallow;
+  private final Set<ObjectId> commitsToIgnore;
 
   /**
    * Lazily initializes #gitLookup assuming that all subsequent calls to this method will be related
@@ -81,7 +88,7 @@ public static GitLookup create(File file, Map<String, String> props) {
     GitLookup.DateSource dateSource = GitLookup.DateSource.valueOf(
         dateSourceString.toUpperCase(Locale.US));
     String checkCommitsCountString = props.get(MAX_COMMITS_LOOKUP_KEY);
-    // Backwads compatibility
+    // Backwards compatibility
     if (checkCommitsCountString == null) {
       checkCommitsCountString = props.get(COPYRIGHT_LAST_YEAR_MAX_COMMITS_LOOKUP_KEY);
     }
@@ -90,6 +97,15 @@ public static GitLookup create(File file, Map<String, String> props) {
       checkCommitsCountString = checkCommitsCountString.trim();
       checkCommitsCount = Integer.parseInt(checkCommitsCountString);
     }
+    String commitsToIgnoreString = props.get(COMMITS_TO_IGNORE_KEY);
+    Set<ObjectId> commitsToIgnore = Collections.emptySet();
+    if (commitsToIgnoreString != null) {
+      commitsToIgnoreString = commitsToIgnoreString.trim();
+      commitsToIgnore = Arrays.stream(commitsToIgnoreString.split(","))
+              .map(String::trim)
+              .map(ObjectId::fromString)
+              .collect(Collectors.toSet());
+    }
     final TimeZone timeZone;
     String tzString = props.get(COPYRIGHT_LAST_YEAR_TIME_ZONE_KEY);
     switch (dateSource) {
@@ -108,7 +124,7 @@ public static GitLookup create(File file, Map<String, String> props) {
         throw new IllegalStateException(
             "Unexpected " + GitLookup.DateSource.class.getName() + " " + dateSource);
     }
-    return new GitLookup(file, dateSource, timeZone, checkCommitsCount);
+    return new GitLookup(file, dateSource, timeZone, checkCommitsCount, commitsToIgnore);
   }
 
   /**
@@ -122,10 +138,11 @@ public static GitLookup create(File file, Map<String, String> props) {
    * @param dateSource        where to read the commit dates from - committer date or author date
    * @param timeZone          the time zone if {@code dateSource} is {@link DateSource#COMMITER};
    *                          otherwise must be {@code null}.
-   * @param checkCommitsCount
+   * @param checkCommitsCount the number of historical commits, per file, to check
+   * @param commitsToIgnore   the commits to ignore while inspecting the history for {@code anyFile}
    * @throws IOException
    */
-  private GitLookup(File anyFile, DateSource dateSource, TimeZone timeZone, int checkCommitsCount) {
+  private GitLookup(File anyFile, DateSource dateSource, TimeZone timeZone, int checkCommitsCount, Set<ObjectId> commitsToIgnore) {
     try {
       this.repository = new FileRepositoryBuilder().findGitDir(anyFile).build();
       /* A workaround for  https://bugs.eclipse.org/bugs/show_bug.cgi?id=457961 */
@@ -155,6 +172,7 @@ private GitLookup(File anyFile, DateSource dateSource, TimeZone timeZone, int ch
               "Unexpected " + DateSource.class.getName() + " " + dateSource);
       }
       this.checkCommitsCount = checkCommitsCount;
+      this.commitsToIgnore = commitsToIgnore;
     } catch (IOException e) {
       throw new UncheckedIOException(e);
     }
@@ -165,7 +183,7 @@ private GitLookup(File anyFile, DateSource dateSource, TimeZone timeZone, int ch
    * year is taken either from the committer date or from the author identity depending on how {@link #dateSource} was
    * initialized.
    * <p>
-   * See also the note on time zones in {@link #GitLookup(File, DateSource, TimeZone, int)}.
+   * See also the note on time zones in {@link #GitLookup(File, DateSource, TimeZone, int, Set)}.
    *
    * @param file for which the year should be retrieved
    * @return year of last modification of the file
@@ -182,6 +200,9 @@ int getYearOfLastChange(File file) throws GitAPIException, IOException {
     int commitYear = 0;
     RevWalk walk = getGitRevWalk(repoRelativePath, false);
     for (RevCommit commit : walk) {
+      if (commitsToIgnore.contains(commit.getId())) {
+        continue;
+      }
       int y = getYearFromCommit(commit);
       if (y > commitYear) {
         commitYear = y;
@@ -314,4 +335,4 @@ private String getAuthorEmailFromCommit(RevCommit commit) {
   public void close() {
     repository.close();
   }
-}
+}

license-maven-plugin-git/src/test/java/com/mycila/maven/plugin/license/git/GitLookupTest.java

@@ -157,7 +157,7 @@ void reuseProvider() throws GitAPIException, IOException {
   @Test
   void timezone() throws GitAPIException, IOException {
     try {
-      GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.AUTHOR, "GMT", "10"));
+      GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.AUTHOR, "GMT", "10", null));
       Assertions.fail("RuntimeException expected");
     } catch (RuntimeException e) {
       if (e.getMessage().contains(
@@ -170,25 +170,25 @@ void timezone() throws GitAPIException, IOException {
 
     /* null is GMT */
     GitLookup nullTzLookup = GitLookup.create(gitRepoRoot.toFile(),
-        buildProps(DateSource.COMMITER, null, "10"));
+        buildProps(DateSource.COMMITER, null, "10", null));
     assertLastChange(nullTzLookup, "dir1/file3.txt", 2010);
 
     /* explicit GMT */
     GitLookup gmtLookup = GitLookup.create(gitRepoRoot.toFile(),
-        buildProps(DateSource.COMMITER, "GMT", "10"));
+        buildProps(DateSource.COMMITER, "GMT", "10", null));
     assertLastChange(gmtLookup, "dir1/file3.txt", 2010);
 
     /*
      * explicit non-GMT zome. Note that the relevant commit's (GMT) time stamp is 2010-12-31T23:30:00 which yealds
      * 2011 in the CET (+01:00) time zone
      */
     GitLookup cetLookup = GitLookup.create(gitRepoRoot.toFile(),
-        buildProps(DateSource.COMMITER, "CET", "10"));
+        buildProps(DateSource.COMMITER, "CET", "10", null));
     assertLastChange(cetLookup, "dir1/file3.txt", 2011);
 
   }
 
-  private Map<String, String> buildProps(DateSource ds, String tz, String history) {
+  private Map<String, String> buildProps(DateSource ds, String tz, String history, String commitsToIgnoreCSV) {
     Map<String, String> props = new HashMap<>();
     if (history != null) {
       props.put(GitLookup.MAX_COMMITS_LOOKUP_KEY, history);
@@ -199,15 +199,40 @@ private Map<String, String> buildProps(DateSource ds, String tz, String history)
     if (ds != null) {
       props.put(GitLookup.COPYRIGHT_LAST_YEAR_SOURCE_KEY, ds.name());
     }
+    if (commitsToIgnoreCSV != null) {
+      props.put(GitLookup.COMMITS_TO_IGNORE_KEY, commitsToIgnoreCSV);
+    }
     return props;
   }
 
   private GitLookup newAuthorLookup() {
-    return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.AUTHOR, null, "10"));
+    return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.AUTHOR, null, "10", null));
   }
 
   private GitLookup newCommitterLookup() {
-    return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.COMMITER, null, "10"));
+    return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.COMMITER, null, "10", null));
+  }
+
+  @Test
+  public void ignoreCommitsInLastChange() throws GitAPIException, IOException {
+    assertLastChange(newAuthorLookup("95d52919cbe340dc271cf1f5ec68cf36705bd3a3"), "dir1/file1.txt", 2004);
+    assertLastChange(newCommitterLookup("95d52919cbe340dc271cf1f5ec68cf36705bd3a3"), "dir1/file1.txt", 2004);
+  }
+
+  @Test
+  public void doNotIgnoreCommitsInCreation() throws GitAPIException, IOException {
+    assertCreation(newAuthorLookup("53b44baedc5a378f9b665da12f298e1003793219"), "dir1/file1.txt", 2000);
+    assertCreation(newCommitterLookup("53b44baedc5a378f9b665da12f298e1003793219"), "dir1/file1.txt", 2000);
+  }
+
+  private GitLookup newAuthorLookup(String... commitsToIgnore) throws IOException {
+    String commitsToIgnoreCSV = String.join(",", commitsToIgnore);
+    return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.AUTHOR, null, "10", commitsToIgnoreCSV));
+  }
+
+  private GitLookup newCommitterLookup(String... commitsToIgnore) throws IOException {
+      String commitsToIgnoreCSV = String.join(",", commitsToIgnore);
+      return GitLookup.create(gitRepoRoot.toFile(), buildProps(DateSource.COMMITER, null, "10", commitsToIgnoreCSV));
   }
 
   private void assertLastChange(GitLookup provider, String relativePath, int expected) throws
@@ -224,4 +249,4 @@ private void assertCreation(GitLookup provider, String relativePath, int expecte
     Assertions.assertEquals(expected, actual);
   }
 
-}
+}