Preserve FXML source ranges and extend shared Component projection

designer-intellij/src/main/java/de/neitzel/fxdesigner/intellij/IntellijDocuments.java

@@ -149,6 +149,21 @@ public final class IntellijDocuments implements HostServices.Documents, AutoClos
     }
   }
 
+  private void refreshClean(State s) throws java.io.IOException {
+    var manager = FileDocumentManager.getInstance();
+    if (manager.isDocumentUnsaved(s.document)) return;
+    String disk = Files.readString(Path.of(s.file.getPath()));
+    if (disk.equals(s.document.getText())) {
+      s.disk = disk; // Native autosave already persisted this revision; do not reload it.
+      return;
+    }
+    if (!disk.equals(s.disk)) {
+      s.file.refresh(false, false);
+      manager.reloadFromDisk(s.document);
+      s.disk = disk;
+    }
+  }
+
   private DocumentSnapshot snapshot(State s) {
     return new DocumentSnapshot(
         canonicalUri(s.file),
@@ -176,12 +191,17 @@ public final class IntellijDocuments implements HostServices.Documents, AutoClos
     }
 
     public CompletionStage<DocumentSnapshot> snapshot() {
-      return run(() -> IntellijDocuments.this.snapshot(s));
+      return run(
+          () -> {
+            refreshClean(s);
+            return IntellijDocuments.this.snapshot(s);
+          });
     }
 
     public CompletionStage<DocumentSnapshot> apply(EditBatch edits) {
       return run(
           () -> {
+            refreshClean(s);
             edits.applyTo(IntellijDocuments.this.snapshot(s));
             var ranges = new ArrayList<>(edits.replacements());
             ranges.sort(Comparator.comparingInt(EditBatch.Replacement::start));

designer-intellij/src/test/java/de/neitzel/fxdesigner/intellij/IntellijDocumentsTest.java

@@ -109,4 +109,54 @@ public final class IntellijDocumentsTest extends BasePlatformTestCase {
       Files.deleteIfExists(directory);
     }
   }
+
+  public void testCleanExternalReloadAndRangeCaretPreservation() throws Exception {
+    Path file = Files.createTempFile("designer-reload-", ".fxml");
+    Files.writeString(file, "prefix value suffix");
+    com.intellij.openapi.vfs.newvfs.impl.VfsRootAccess.allowRootAccess(
+        getTestRootDisposable(), file.toRealPath().toString());
+    try (var docs = new IntellijDocuments(getProject());
+        var handle = docs.open(file.toUri()).toCompletableFuture().get()) {
+      var initial = handle.snapshot().toCompletableFuture().get();
+      Files.writeString(file, "prefix external suffix");
+      var current = handle.snapshot().toCompletableFuture().get();
+      assertEquals("prefix external suffix", current.text());
+      assertFalse(current.dirty());
+      assertTrue(initial.revision() != current.revision());
+      var vf =
+          com.intellij.openapi.vfs.LocalFileSystem.getInstance().refreshAndFindFileByNioFile(file);
+      var document =
+          com.intellij.openapi.fileEditor.FileDocumentManager.getInstance().getDocument(vf);
+      var editor =
+          com.intellij.openapi.editor.EditorFactory.getInstance()
+              .createEditor(document, getProject());
+      try {
+        editor.getCaretModel().moveToOffset(current.text().length());
+        editor
+            .getSelectionModel()
+            .setSelection(current.text().indexOf("suffix"), current.text().length());
+        var updated =
+            handle
+                .apply(
+                    new EditBatch(
+                        current.revision(),
+                        "Range edit",
+                        List.of(new EditBatch.Replacement(7, 15, "X"))))
+                .toCompletableFuture()
+                .get();
+        assertEquals("prefix X suffix", updated.text());
+        assertEquals("suffix", editor.getSelectionModel().getSelectedText());
+        assertEquals(updated.text().length(), editor.getCaretModel().getOffset());
+        com.intellij.openapi.fileEditor.FileDocumentManager.getInstance().saveDocument(document);
+        var saved = handle.snapshot().toCompletableFuture().get();
+        assertEquals(updated.revision(), saved.revision());
+        assertFalse(saved.dirty());
+        handle.save(updated.revision()).toCompletableFuture().get();
+      } finally {
+        com.intellij.openapi.editor.EditorFactory.getInstance().releaseEditor(editor);
+      }
+    } finally {
+      Files.deleteIfExists(file);
+    }
+  }
 }