IDEA-196620 git: do not suggest rename with extra commit it is not available (actual fix disabled)

Kotlin plugin erases its internal flags on `collectExplicitMovements` call.
Thus, second call will return empty collection, and we can't use it to update checkbox state.

But we can prepare API and enable registry key when fixed plugin version is available.

platform/util/resources/misc/registry.properties

@@ -1150,6 +1150,7 @@ git.refresh.vfs.total.description=If set to true, the whole Git repository root
   The option is needed to debug possible "incomplete VFS refresh" reports, if they appear.  
 git.allow.explicit.commit.renames=true
 git.allow.explicit.commit.renames.description=Enable option to commit some "rename + modification" as two commits to help git track file history (ex: for files, converted from Java to Kotlin).
+git.explicit.commit.renames.allow.multiple.calls=false
 git.force.commit.using.staging.area=true
 git.force.commit.using.staging.area.description=When enabled, perform all git commits by updating staging area. If disabled, use `git commit --only` when possible.
 git.clone.recurse.submodules=true

plugins/git4idea/src/git4idea/checkin/GitCheckinEnvironment.java

@@ -524,7 +524,7 @@ public class GitCheckinEnvironment implements CheckinEnvironment {
 
     Set<Movement> movedPaths = new HashSet<>();
     for (GitCheckinExplicitMovementProvider provider : GitCheckinExplicitMovementProvider.EP_NAME.getExtensions()) {
-      Collection<Movement> providerMovements = provider.collectExplicitMovements(myProject, beforePaths, afterPaths);
+      Collection<Movement> providerMovements = provider.collectExplicitMovements(myProject, beforePaths, afterPaths, true);
       if (!providerMovements.isEmpty()) {
         message = provider.getCommitMessage(message);
         movedPaths.addAll(providerMovements);
@@ -1101,7 +1101,7 @@ public class GitCheckinEnvironment implements CheckinEnvironment {
 
 
     GitCheckinOptions(@NotNull Project project, @NotNull CheckinProjectPanel panel) {
-      myExplicitMovementProviders = filter(GitCheckinExplicitMovementProvider.EP_NAME.getExtensions(), it -> it.isEnabled(myProject));
+      myExplicitMovementProviders = collectActiveMovementProviders(myProject);
 
       myCheckinProjectPanel = panel;
       myAuthorField = createTextField(project, getAuthors(project));
@@ -1332,6 +1332,20 @@ public class GitCheckinEnvironment implements CheckinEnvironment {
       GitUserRegistry gitUserRegistry = GitUserRegistry.getInstance(myProject);
       return of(affectedGitRoots).map(vf -> gitUserRegistry.getUser(vf)).allMatch(user -> user != null && isSamePerson(author, user));
     }
+
+    @NotNull
+    private List<GitCheckinExplicitMovementProvider> collectActiveMovementProviders(@NotNull Project project) {
+      GitCheckinExplicitMovementProvider[] allProviders = GitCheckinExplicitMovementProvider.EP_NAME.getExtensions();
+      List<GitCheckinExplicitMovementProvider> enabledProviders = filter(allProviders, it -> it.isEnabled(project));
+      if (enabledProviders.isEmpty()) return Collections.emptyList();
+      if (!Registry.is("git.explicit.commit.renames.allow.multiple.calls")) return enabledProviders;
+
+      Collection<Change> changes = ChangeListManager.getInstance(project).getAllChanges();
+      List<FilePath> beforePaths = mapNotNull(changes, ChangesUtil::getBeforePath);
+      List<FilePath> afterPaths = mapNotNull(changes, ChangesUtil::getAfterPath);
+
+      return filter(enabledProviders, it -> !it.collectExplicitMovements(project, beforePaths, afterPaths, false).isEmpty());
+    }
   }
 
   public void setNextCommitIsPushed(Boolean nextCommitIsPushed) {

plugins/git4idea/src/git4idea/checkin/GitCheckinExplicitMovementProvider.java

@@ -4,6 +4,7 @@ package git4idea.checkin;
 import com.intellij.openapi.extensions.ExtensionPointName;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.vcs.FilePath;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Collection;
@@ -18,6 +19,7 @@ import java.util.Objects;
  * This will create two commits: commit with explicit file movements,
  * and commit with content modifications in these files and the rest of affected files
  */
+@ApiStatus.Experimental
 public abstract class GitCheckinExplicitMovementProvider {
   public static final ExtensionPointName<GitCheckinExplicitMovementProvider> EP_NAME =
     ExtensionPointName.create("Git4Idea.GitCheckinExplicitMovementProvider");
@@ -36,13 +38,27 @@ public abstract class GitCheckinExplicitMovementProvider {
   @NotNull
   public abstract String getCommitMessage(@NotNull String originalCommitMessage);
 
+
+  @Deprecated
+  @NotNull
+  public Collection<Movement> collectExplicitMovements(@NotNull Project project,
+                                                       @NotNull List<FilePath> beforePaths,
+                                                       @NotNull List<FilePath> afterPaths) {
+    throw new UnsupportedOperationException();
+  }
+
   /**
+   * @param isActualCommit Whether actual commit will be performed or it's an intermediate check to update UI
+   *
    * @return file movements, that should be committed explicitly
    */
   @NotNull
-  public abstract Collection<Movement> collectExplicitMovements(@NotNull Project project,
-                                                                @NotNull List<FilePath> beforePaths,
-                                                                @NotNull List<FilePath> afterPaths);
+  public Collection<Movement> collectExplicitMovements(@NotNull Project project,
+                                                       @NotNull List<FilePath> beforePaths,
+                                                       @NotNull List<FilePath> afterPaths,
+                                                       boolean isActualCommit) {
+    return collectExplicitMovements(project, beforePaths, afterPaths);
+  }
 
   public static class Movement {
     @NotNull private final FilePath myBeforePath;