IDEA-141883 .gitignore in the repository that tracks the settings is not respected

1) support .gitignore only in the repository root
2) changes is not tracked — to apply changed file IDE must be restarted.

plugins/settings-repository/src/BaseRepositoryManager.kt

@@ -103,7 +103,7 @@ public abstract class BaseRepositoryManager(protected val dir: File) : Repositor
     return null
   }
 
-  override fun write(path: String, content: ByteArray, size: Int) {
+  override fun write(path: String, content: ByteArray, size: Int): Boolean {
     if (LOG.isDebugEnabled()) {
       LOG.debug("Write $path")
     }
@@ -118,7 +118,9 @@ public abstract class BaseRepositoryManager(protected val dir: File) : Repositor
     }
     catch (e: Exception) {
       LOG.error(e)
+      return false
     }
+    return true
   }
 
   /**

plugins/settings-repository/src/IcsManager.kt

@@ -215,16 +215,12 @@ class IcsManager(dir: File) {
         throw IllegalStateException("Save is prohibited now")
       }
 
-      doSave(fileSpec, content, size, roamingType)
-
-      if (isAutoCommit(fileSpec, roamingType)) {
+      if (doSave(fileSpec, content, size, roamingType) && isAutoCommit(fileSpec, roamingType)) {
         scheduleCommit()
       }
     }
 
-    fun doSave(fileSpec: String, content: ByteArray, size: Int, roamingType: RoamingType) {
-      repositoryManager.write(buildPath(fileSpec, roamingType, projectId), content, size)
-    }
+    fun doSave(fileSpec: String, content: ByteArray, size: Int, roamingType: RoamingType) = repositoryManager.write(buildPath(fileSpec, roamingType, projectId), content, size)
 
     protected open fun isAutoCommit(fileSpec: String, roamingType: RoamingType): Boolean = true
 

plugins/settings-repository/src/RepositoryManager.kt

@@ -41,7 +41,10 @@ public interface RepositoryManager {
 
   public fun read(path: String): InputStream?
 
-  public fun write(path: String, content: ByteArray, size: Int)
+  /**
+   * Returns false if file is not written (for example, due to ignore rules).
+   */
+  public fun write(path: String, content: ByteArray, size: Int): Boolean
 
   public fun delete(path: String)
 

plugins/settings-repository/src/git/GitRepositoryManager.kt

@@ -26,6 +26,7 @@ import com.intellij.util.SmartList
 import org.eclipse.jgit.api.AddCommand
 import org.eclipse.jgit.api.errors.UnmergedPathsException
 import org.eclipse.jgit.errors.TransportException
+import org.eclipse.jgit.ignore.IgnoreNode
 import org.eclipse.jgit.lib.ConfigConstants
 import org.eclipse.jgit.lib.Constants
 import org.eclipse.jgit.lib.Repository
@@ -62,6 +63,8 @@ class GitRepositoryManager(private val credentialsStore: NotNullLazyValue<Creden
     JGitCredentialsProvider(credentialsStore, repository)
   }
 
+  private var ignoreRules: IgnoreNode? = null
+
   init {
     if (ApplicationManager.getApplication()?.isUnitTestMode() != true) {
       ShutDownTracker.getInstance().registerShutdownTask(object: Runnable {
@@ -73,6 +76,8 @@ class GitRepositoryManager(private val credentialsStore: NotNullLazyValue<Creden
   }
 
   override fun createRepositoryIfNeed(): Boolean {
+    ignoreRules = null
+
     if (isRepositoryExists()) {
       return false
     }
@@ -83,6 +88,8 @@ class GitRepositoryManager(private val credentialsStore: NotNullLazyValue<Creden
   }
 
   override fun deleteRepository() {
+    ignoreRules = null
+
     super.deleteRepository()
 
     val r = _repository
@@ -276,6 +283,28 @@ class GitRepositoryManager(private val credentialsStore: NotNullLazyValue<Creden
     repository.commit(with(IdeaCommitMessageFormatter()) { StringBuilder().appendCommitOwnerInfo(true) } .append("Get rid of \$ROOT_CONFIG$ and \$APP_CONFIG").toString())
     return true
   }
+
+  private fun getIgnoreRules(): IgnoreNode? {
+    var node = ignoreRules
+    if (node == null) {
+      val file = File(dir, Constants.DOT_GIT_IGNORE)
+      if (file.exists()) {
+        node = IgnoreNode()
+        file.inputStream().use { node!!.parse(it) }
+        ignoreRules = node
+      }
+    }
+    return node
+  }
+
+  override fun write(path: String, content: ByteArray, size: Int): Boolean {
+    val ignoreRules = getIgnoreRules()
+    // add first slash as WorkingTreeIterator does "The ignore code wants path to start with a '/' if possible."
+    if (ignoreRules != null && ignoreRules.isIgnored("/$path", false) == IgnoreNode.MatchResult.IGNORED) {
+      return false
+    }
+    return super.write(path, content, size)
+  }
 }
 
 fun printMessages(fetchResult: OperationResult) {

plugins/settings-repository/testSrc/GitTest.kt

@@ -343,6 +343,25 @@ class GitTest : IcsTestCase() {
     doSyncWithUninitializedUpstream(SyncType.OVERWRITE_LOCAL)
   }
 
+  Test fun gitignore() {
+    createLocalRepository()
+
+    repository.add(".gitignore", "*.html")
+    sync(SyncType.MERGE)
+
+    provider.write("bar.html", "<data />")
+    provider.write("i/am/a/long/path/to/file/foo.html", "<data />")
+
+    val diff = repository.computeIndexDiff()
+    assertThat(diff.diff()).isFalse()
+    assertThat(diff.getAdded()).isEmpty()
+    assertThat(diff.getChanged()).isEmpty()
+    assertThat(diff.getRemoved()).isEmpty()
+    assertThat(diff.getModified()).isEmpty()
+    assertThat(diff.getUntracked()).isEmpty()
+    assertThat(diff.getUntrackedFolders()).isEmpty()
+  }
+
   private fun createRemoteRepository(branchName: String? = null, initialCommit: Boolean = true) {
     val repository = tempDirManager.createRepository("upstream")
     if (initialCommit) {