added raw header to hunk

scm-core/src/main/java/sonia/scm/repository/api/Hunk.java

@@ -2,6 +2,18 @@ package sonia.scm.repository.api;
 
 public interface Hunk extends Iterable<DiffLine> {
 
+  default String getRawHeader() {
+    return String.format("@@ -%s +%s @@", getLineMarker(getOldStart(), getOldLineCount()), getLineMarker(getNewStart(), getNewLineCount()));
+  }
+
+  default String getLineMarker(int start, int lineCount) {
+    if (lineCount == 1) {
+      return Integer.toString(start);
+    } else {
+      return String.format("%s,%s", start, lineCount);
+    }
+  }
+
   int getOldStart();
 
   int getOldLineCount();

scm-core/src/test/java/sonia/scm/repository/api/HunkTest.java

@@ -0,0 +1,53 @@
+package sonia.scm.repository.api;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Iterator;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class HunkTest {
+
+  @Test
+  void shouldGetComplexHeader() {
+    String rawHeader = createHunk(2, 3, 4, 5).getRawHeader();
+
+    assertThat(rawHeader).isEqualTo("@@ -2,3 +4,5 @@");
+  }
+
+  @Test
+  void shouldReturnSingleNumberForOne() {
+    String rawHeader = createHunk(42, 1, 5, 1).getRawHeader();
+
+    assertThat(rawHeader).isEqualTo("@@ -42 +5 @@");
+  }
+
+  private Hunk createHunk(int oldStart, int oldLineCount, int newStart, int newLineCount) {
+    return new Hunk() {
+      @Override
+      public int getOldStart() {
+        return oldStart;
+      }
+
+      @Override
+      public int getOldLineCount() {
+        return oldLineCount;
+      }
+
+      @Override
+      public int getNewStart() {
+        return newStart;
+      }
+
+      @Override
+      public int getNewLineCount() {
+        return newLineCount;
+      }
+
+      @Override
+      public Iterator<DiffLine> iterator() {
+        return null;
+      }
+    };
+  }
+}