Bug 1548256 - Blank debugger when hovering variables. r=davidwalsh

Differential Revision: https://phabricator.services.mozilla.com/D30246

--HG--
extra : moz-landing-system : lando

devtools/client/debugger/src/actions/preview.js

@@ -118,6 +118,12 @@ export function setPreview(
           return;
         }
 
+        // Handle cases where the result is invisible to the debugger
+        // and not possible to preview. Bug 1548256
+        if (result.class && result.class.includes("InvisibleToDebugger")) {
+          return;
+        }
+
         const root = {
           name: expression,
           path: expression,

devtools/client/debugger/src/client/firefox/commands.js

@@ -264,7 +264,7 @@ type EvaluateParam = { thread: string, frameId: ?FrameId };
 function evaluate(
   script: ?Script,
   { thread, frameId }: EvaluateParam = {}
-): Promise<{ result: ?Object }> {
+): Promise<{ result: Grip | null }> {
   const params = { thread, frameActor: frameId };
   if (!tabTarget || !script) {
     return Promise.resolve({ result: null });

devtools/client/debugger/src/client/firefox/tests/commands.spec.js

@@ -24,6 +24,27 @@ function makeDependencies() {
   };
 }
 
+function makeGrip(actor = "") {
+  return {
+    actor,
+    class: "",
+    displayClass: "",
+    name: "",
+    extensible: true,
+    location: {
+      url: "",
+      line: 2,
+      column: 34
+    },
+    frozen: false,
+    ownPropertyLength: 1,
+    preview: {},
+    sealed: false,
+    optimizedOut: false,
+    type: ""
+  };
+}
+
 describe("firefox commands", () => {
   describe("getProperties", () => {
     it("empty response", async () => {
@@ -34,7 +55,7 @@ describe("firefox commands", () => {
       });
 
       setupCommands({ ...makeDependencies(), threadClient });
-      const props = await getProperties("", { actor: "" });
+      const props = await getProperties("", makeGrip());
       expect(props).toMatchSnapshot();
     });
 
@@ -49,7 +70,7 @@ describe("firefox commands", () => {
       });
 
       setupCommands({ ...makeDependencies(), threadClient });
-      const props = await getProperties("", { actor: "" });
+      const props = await getProperties("", makeGrip());
       expect(props).toMatchSnapshot();
     });
 
@@ -66,7 +87,7 @@ describe("firefox commands", () => {
       });
 
       setupCommands({ ...makeDependencies(), threadClient });
-      const props = await getProperties("", { actor: "" });
+      const props = await getProperties("", makeGrip());
       expect(props).toMatchSnapshot();
     });
 
@@ -82,7 +103,7 @@ describe("firefox commands", () => {
       });
 
       setupCommands({ ...makeDependencies(), threadClient });
-      const props = await getProperties("", { actor: "" });
+      const props = await getProperties("", makeGrip());
       expect(props).toMatchSnapshot();
     });
   });

devtools/client/debugger/src/client/firefox/types.js

@@ -209,7 +209,7 @@ export type TabTarget = {
       script: Script,
       func: Function,
       params?: { frameActor: ?FrameId }
-    ) => Promise<{ result: ?Object }>,
+    ) => Promise<{ result: Grip | null }>,
     autocomplete: (
       input: string,
       cursor: number,
@@ -277,9 +277,26 @@ export type TabClient = {
  * @memberof firefox
  * @static
  */
-// FIXME: need Grip definition
 export type Grip = {
-  actor: string
+  actor: string,
+  class: string,
+  displayClass: string,
+  displayName?: string,
+  parameterNames?: string[],
+  userDisplayName?: string,
+  name: string,
+  extensible: boolean,
+  location: {
+    url: string,
+    line: number,
+    column: number
+  },
+  frozen: boolean,
+  ownPropertyLength: number,
+  preview: Object,
+  sealed: boolean,
+  optimizedOut: boolean,
+  type: string
 };
 
 export type FunctionGrip = {|