Fix broken devtools inspector source navigation (#8058)

Restores source navigation from the embedded devtools inspector.

Fixes: #8041

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Author: pq

flutter-idea/src/io/flutter/devtools/DevToolsUtils.java

@@ -5,12 +5,32 @@
  */
 package io.flutter.devtools;
 
+import com.intellij.openapi.application.Application;
 import com.intellij.openapi.editor.colors.EditorColorsManager;
+import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.ui.ColorUtil;
 import com.intellij.ui.JBColor;
 import com.intellij.util.ui.UIUtil;
+import org.dartlang.vm.service.VmService;
+import org.dartlang.vm.service.VmServiceListener;
 import org.jetbrains.annotations.NotNull;
 
+import org.dartlang.vm.service.element.Event;
+
+import com.google.gson.JsonObject;
+import com.intellij.openapi.application.ApplicationManager;
+import com.intellij.openapi.vfs.LocalFileSystem;
+import com.intellij.xdebugger.impl.XSourcePositionImpl;
+import io.flutter.run.daemon.FlutterApp;
+import io.flutter.utils.JsonUtils;
+import org.dartlang.vm.service.element.*;
+import org.jetbrains.annotations.Nullable;
+
+import java.net.MalformedURLException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.*;
+
 public class DevToolsUtils {
   public static String findWidgetId(String url) {
     final String searchFor = "inspectorRef=";
@@ -23,6 +43,75 @@ public static String findWidgetId(String url) {
     return null;
   }
 
+  /**
+   * Register a VM listener that listens for devtools "ToolEvent"s.
+   * @param app the associated app
+   */
+  public static void registerDevToolsVmServiceListener(@NotNull FlutterApp app) {
+    // This functionality lived originally in the `FlutterInspectorService` introduced in:
+    // https://github.com/flutter/flutter-intellij/pull/6881
+    //
+    // It was mistakenly removed in: https://github.com/flutter/flutter-intellij/pull/7867
+    //
+    // TODO(pq): some follow-ups:
+    //  * consider a better long-term home for this utility
+    //  * do we need to de-register?
+
+    VmService vmService = app.getVmService();
+    if (vmService == null) return;
+
+    vmService.addVmServiceListener(new VmServiceListener() {
+      @Override
+      public void connectionOpened() { }
+
+      @Override
+      public void received(String streamId, Event event) {
+        if (streamId != null) {
+          onVmServiceReceived(app, streamId, event);
+        }
+      }
+
+      @Override
+      public void connectionClosed() { }
+    });
+  }
+
+  private static void onVmServiceReceived(@NotNull FlutterApp app, @NotNull String streamId, @Nullable Event event) {
+    Application application = ApplicationManager.getApplication();
+    if (application == null) return;
+
+    if (streamId.equals("ToolEvent")) {
+      Optional<Event> eventOrNull = Optional.ofNullable(event);
+      if ("navigate".equals(eventOrNull.map(Event::getExtensionKind).orElse(null))) {
+        JsonObject json = eventOrNull.map(Event::getExtensionData).map(ExtensionData::getJson).orElse(null);
+        if (json == null) return;
+
+        String fileUri = JsonUtils.getStringMember(json, "fileUri");
+        if (fileUri == null) return;
+
+        String path = null;
+        try {
+          path = new URI(fileUri).toURL().getFile();
+        }
+        catch (MalformedURLException | URISyntaxException e) {
+          // A null path will cause an early return.
+        }
+        if (path == null) return;
+
+        VirtualFile file = LocalFileSystem.getInstance().findFileByPath(path);
+        int line = JsonUtils.getIntMember(json, "line");
+        int column = JsonUtils.getIntMember(json, "column");
+
+        application.invokeLater(() -> {
+          if (file != null && line >= 0 && column >= 0) {
+            XSourcePositionImpl position = XSourcePositionImpl.create(file, line - 1, column - 1);
+            position.createNavigatable(app.getProject()).navigate(false);
+          }
+        });
+      }
+    }
+  }
+
   public String getColorHexCode() {
     return ColorUtil.toHex(UIUtil.getEditorPaneBackground());
   }
@@ -37,6 +126,6 @@ public Boolean getIsBackgroundBright() {
       // Return the default normal font size if editor manager is not found.
       return UIUtil.getFontSize(UIUtil.FontSize.NORMAL);
     }
-    return (float) manager.getGlobalScheme().getEditorFontSize();
+    return (float)manager.getGlobalScheme().getEditorFontSize();
   }
 }

flutter-idea/src/io/flutter/view/FlutterView.java

@@ -33,6 +33,7 @@
 import io.flutter.bazel.WorkspaceCache;
 import io.flutter.devtools.DevToolsIdeFeature;
 import io.flutter.devtools.DevToolsUrl;
+import io.flutter.devtools.DevToolsUtils;
 import io.flutter.jxbrowser.FailureType;
 import io.flutter.jxbrowser.InstallationFailedReason;
 import io.flutter.jxbrowser.JxBrowserManager;
@@ -49,6 +50,7 @@
 import io.flutter.utils.EventStream;
 import io.flutter.utils.JxBrowserUtils;
 import io.flutter.utils.LabelInput;
+import org.dartlang.vm.service.VmService;
 import org.jetbrains.annotations.NotNull;
 
 import javax.swing.*;
@@ -161,6 +163,14 @@ private void addBrowserInspectorViewContent(FlutterApp app,
     FlutterSdk flutterSdk = FlutterSdk.getFlutterSdk(app.getProject());
     FlutterSdkVersion flutterSdkVersion = flutterSdk == null ? null : flutterSdk.getVersion();
 
+
+    // Register for devtools events (required for inspector->editor source linking)
+    // See: https://github.com/flutter/flutter-intellij/issues/8041
+    VmService vmService = app.getVmService();
+    if (vmService != null) {
+      DevToolsUtils.registerDevToolsVmServiceListener(app);
+    }
+
     if (isEmbedded) {
       final DevToolsUrl devToolsUrl = new DevToolsUrl.Builder()
         .setDevToolsHost(devToolsInstance.host())