Migrate java-diff-utils version to 4.0

The source of java diff utils 4.0 was added at unknown commit.

The old java-diff-utils library is no longer maintained and with a problematic LICENSE file [1].
The new version is a fork of the original version which is under maintenance and fixed the LICENSE problem.

[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=845471#52

conga-relnote: n/a
RELNOTES: None
PiperOrigin-RevId: 317628549

src/main/java/com/google/devtools/build/lib/bazel/repository/BUILD

@@ -46,9 +46,9 @@ java_library(
         "//src/main/java/com/google/devtools/common/options",
         "//third_party:apache_commons_compress",
         "//third_party:auto_value",
-        "//third_party:diffutils",
         "//third_party:flogger",
         "//third_party:guava",
+        "//third_party:java-diff-utils",
         "//third_party:jsr305",
         "//third_party:xz",
     ],

src/main/java/com/google/devtools/build/lib/bazel/repository/PatchUtil.java

@@ -14,19 +14,21 @@
 
 package com.google.devtools.build.lib.bazel.repository;
 
+import com.github.difflib.UnifiedDiffUtils;
+import com.github.difflib.patch.AbstractDelta;
+import com.github.difflib.patch.ChangeDelta;
+import com.github.difflib.patch.Chunk;
+import com.github.difflib.patch.DeleteDelta;
+import com.github.difflib.patch.InsertDelta;
+import com.github.difflib.patch.Patch;
+import com.github.difflib.patch.PatchFailedException;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Splitter;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.Path;
-import difflib.Chunk;
-import difflib.Delta;
-import difflib.DeltaComparator;
-import difflib.DiffUtils;
-import difflib.Patch;
-import difflib.PatchFailedException;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
@@ -83,11 +85,10 @@ private static class OffsetPatch {
 
     public static List<String> applyTo(Patch<String> patch, List<String> target)
         throws PatchFailedException {
-      List<Delta<String>> deltas = patch.getDeltas();
+      List<AbstractDelta<String>> deltas = patch.getDeltas();
       List<String> result = new ArrayList<>(target);
-      deltas.sort(DeltaComparator.INSTANCE);
-      for (Delta<String> item : Lists.reverse(deltas)) {
-        Delta<String> delta = item;
+      for (AbstractDelta<String> item : Lists.reverse(deltas)) {
+        AbstractDelta<String> delta = item;
         applyTo(delta, result);
       }
 
@@ -99,15 +100,15 @@ public static List<String> applyTo(Patch<String> patch, List<String> target)
      * to apply the Delta with an offset, starting from 1, up to the total lines in the original
      * content. For every offset, we try both forwards and backwards.
      */
-    private static void applyTo(Delta<String> delta, List<String> result)
+    private static void applyTo(AbstractDelta<String> delta, List<String> result)
         throws PatchFailedException {
       PatchFailedException e = applyDelta(delta, result);
       if (e == null) {
         return;
       }
 
-      Chunk<String> original = delta.getOriginal();
-      Chunk<String> revised = delta.getRevised();
+      Chunk<String> original = delta.getSource();
+      Chunk<String> revised = delta.getTarget();
       int[] direction = {1, -1};
       int maxOffset = result.size();
       for (int i = 1; i < maxOffset; i++) {
@@ -116,9 +117,25 @@ private static void applyTo(Delta<String> delta, List<String> result)
           if (offset + original.getPosition() < 0 || offset + revised.getPosition() < 0) {
             continue;
           }
-          delta.setOriginal(new Chunk<>(original.getPosition() + offset, original.getLines()));
-          delta.setRevised(new Chunk<>(revised.getPosition() + offset, revised.getLines()));
-          PatchFailedException exception = applyDelta(delta, result);
+          Chunk<String> source = new Chunk<>(original.getPosition() + offset, original.getLines());
+          Chunk<String> target = new Chunk<>(revised.getPosition() + offset, revised.getLines());
+          AbstractDelta<String> newDelta = null;
+          switch (delta.getType()) {
+            case CHANGE:
+              newDelta = new ChangeDelta<>(source, target);
+              break;
+            case INSERT:
+              newDelta = new InsertDelta<>(source, target);
+              break;
+            case DELETE:
+              newDelta = new DeleteDelta<>(source, target);
+              break;
+            case EQUAL:
+          }
+          PatchFailedException exception = null;
+          if (newDelta != null) {
+            exception = applyDelta(newDelta, result);
+          }
           if (exception == null) {
             return;
           }
@@ -128,19 +145,20 @@ private static void applyTo(Delta<String> delta, List<String> result)
       throw e;
     }
 
-    private static PatchFailedException applyDelta(Delta<String> delta, List<String> result) {
+    private static PatchFailedException applyDelta(
+        AbstractDelta<String> delta, List<String> result) {
       try {
         delta.applyTo(result);
         return null;
       } catch (PatchFailedException e) {
         String msg =
             String.join(
                 "\n",
-                "**Original Position**: " + (delta.getOriginal().getPosition() + 1) + "\n",
+                "**Original Position**: " + (delta.getSource().getPosition() + 1) + "\n",
                 "**Original Content**:",
-                String.join("\n", delta.getOriginal().getLines()) + "\n",
+                String.join("\n", delta.getSource().getLines()) + "\n",
                 "**Revised Content**:",
-                String.join("\n", delta.getRevised().getLines()) + "\n");
+                String.join("\n", delta.getTarget().getLines()) + "\n");
         return new PatchFailedException(e.getMessage() + "\n" + msg);
       }
     }
@@ -435,8 +453,7 @@ private static void checkFilesStatusForPatching(
 
     // Does this patch look like adding a new file.
     boolean isAddFile =
-        patch.getDeltas().size() == 1
-            && patch.getDeltas().get(0).getOriginal().getLines().isEmpty();
+        patch.getDeltas().size() == 1 && patch.getDeltas().get(0).getSource().getLines().isEmpty();
 
     // If this patch is not adding a new file,
     // then either old file or new file should be specified and exists,
@@ -620,7 +637,7 @@ public static void apply(Path patchFile, int strip, Path outputDirectory)
                   oldFile, newFile, oldFileStr, newFileStr, patchStartLocation);
             }
 
-            Patch<String> patch = DiffUtils.parseUnifiedDiff(patchContent);
+            Patch<String> patch = UnifiedDiffUtils.parseUnifiedDiff(patchContent);
             checkFilesStatusForPatching(
                 patch, oldFile, newFile, oldFileStr, newFileStr, patchStartLocation);
 
@@ -660,4 +677,6 @@ public static void apply(Path patchFile, int strip, Path outputDirectory)
       }
     }
   }
+
+  private PatchUtil() {}
 }

src/main/java/com/google/devtools/build/lib/bazel/repository/starlark/BUILD

@@ -48,8 +48,8 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/main/java/com/google/devtools/build/skyframe",
         "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
-        "//third_party:diffutils",
         "//third_party:guava",
+        "//third_party:java-diff-utils",
         "//third_party:jsr305",
     ],
 )

src/main/java/com/google/devtools/build/lib/bazel/repository/starlark/StarlarkRepositoryContext.java

@@ -14,6 +14,7 @@
 
 package com.google.devtools.build.lib.bazel.repository.starlark;
 
+import com.github.difflib.patch.PatchFailedException;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Ascii;
 import com.google.common.base.Joiner;
@@ -72,7 +73,6 @@
 import com.google.devtools.build.skyframe.SkyFunction.Environment;
 import com.google.devtools.build.skyframe.SkyFunctionException.Transience;
 import com.google.devtools.build.skyframe.SkyKey;
-import difflib.PatchFailedException;
 import java.io.File;
 import java.io.IOException;
 import java.io.OutputStream;

src/test/java/com/google/devtools/build/lib/bazel/repository/BUILD

@@ -43,8 +43,8 @@ java_library(
         "//src/test/java/com/google/devtools/build/lib/testutil",
         "//src/test/java/com/google/devtools/build/lib/testutil:TestConstants",
         "//src/test/java/com/google/devtools/build/lib/testutil:TestUtils",
-        "//third_party:diffutils",
         "//third_party:guava",
+        "//third_party:java-diff-utils",
         "//third_party:junit4",
         "//third_party:mockito",
         "//third_party:truth",

src/test/java/com/google/devtools/build/lib/bazel/repository/PatchUtilTest.java

@@ -17,12 +17,12 @@
 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertThrows;
 
+import com.github.difflib.patch.PatchFailedException;
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.testutil.Scratch;
 import com.google.devtools.build.lib.vfs.FileSystem;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.inmemoryfs.InMemoryFileSystem;
-import difflib.PatchFailedException;
 import java.io.IOException;
 import org.junit.Before;
 import org.junit.Test;