git: correctly detect if there are local changes that should be saved before update: IDEA-76760

The "AD" status (staged addition + unstaged deletion of the same file) is not detected as a local change, thus we add an additional check for `git diff --staged`.

Note: stashing "AD" would stash only the addition, thus after stash-unstash process the file will be created back. However, it seems to be a less serious issue than unability to update.

plugins/git4idea/src/git4idea/update/GitRebaseUpdater.java

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2011 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package git4idea.update;
 
 import com.intellij.openapi.diagnostic.Logger;
@@ -67,7 +53,14 @@ public class GitRebaseUpdater extends GitUpdater {
   public boolean isSaveNeeded() {
     Collection<Change> localChanges = new LocalChangesUnderRoots(myChangeListManager, myVcsManager)
       .getChangesUnderRoots(singletonList(myRoot)).get(myRoot);
-    return !ContainerUtil.isEmpty(localChanges);
+    try {
+      return !ContainerUtil.isEmpty(localChanges) ||
+             GitUtil.hasLocalChanges(true, myProject, myRoot);
+    }
+    catch (VcsException e) {
+      LOG.info("isSaveNeeded failed to check local changes", e);
+      return true;
+    }
   }
 
   @NotNull

plugins/git4idea/tests/git4idea/test/GitExecutor.kt

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2014 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 @file:JvmName("GitExecutor")
 
 package git4idea.test
@@ -30,6 +16,7 @@ import git4idea.commands.GitLineHandler
 import git4idea.commands.getGitCommandInstance
 import git4idea.repo.GitRepository
 import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
 import java.io.File
 
 fun gitExecutable() = GitExecutorHolder.PathHolder.GIT_EXECUTABLE
@@ -205,6 +192,12 @@ internal class TestFile internal constructor(val repo: GitRepository, val file:
     return this
   }
 
+  fun delete(): TestFile {
+    assertTrue(file.exists())
+    FileUtil.delete(file)
+    return this
+  }
+
   fun assertNotExists(): TestFile {
     assertFalse(file.exists())
     return this

plugins/git4idea/tests/git4idea/update/GitSingleRepoUpdateTest.kt

@@ -1,18 +1,4 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package git4idea.update
 
 import com.intellij.openapi.progress.EmptyProgressIndicator
@@ -89,6 +75,25 @@ class GitSingleRepoUpdateTest : GitUpdateBaseTest() {
     assertFalse("Stash shouldn't be called for clean working tree", stashCalled)
   }
 
+  // IDEA-76760
+  fun `test stash is called for rebase in case of AD changes`() {
+    broRepo.commitAndPush()
+
+    var stashCalled = false
+    git.stashListener = {
+      stashCalled = true
+    }
+
+    cd(repo)
+    val file = file("a.txt").create().add().delete().file
+    updateChangeListManager()
+
+    val result = updateWithRebase()
+    assertSuccessfulUpdate(result)
+    assertTrue("Stash should be called for clean working tree", stashCalled)
+    repo.assertStatus(file, 'A')
+  }
+
   private fun updateWithRebase(): GitUpdateResult {
     return GitUpdateProcess(project, EmptyProgressIndicator(), listOf(repo), UpdatedFiles.create(), false, true).update(UpdateMethod.REBASE)
   }