[api-minor] Support Named-actions in the outline (issue 15367)

Apparently this is implemented in e.g. Adobe Reader, and the specification does support it, however it cannot be commonly used in real-world PDF documents since it took over ten years for this feature to be requested.

src/core/catalog.js

@@ -302,7 +302,7 @@ class Catalog {
         throw new FormatError("Invalid outline item encountered.");
       }
 
-      const data = { url: null, dest: null };
+      const data = { url: null, dest: null, action: null };
       Catalog.parseDestDictionary({
         destDict: outlineDict,
         resultObj: data,
@@ -324,6 +324,7 @@ class Catalog {
       }
 
       const outlineItem = {
+        action: data.action,
         dest: data.dest,
         url: data.url,
         unsafeUrl: data.unsafeUrl,

test/pdfs/.gitignore

@@ -50,6 +50,7 @@
 !issue7439.pdf
 !issue7847_radial.pdf
 !issue14953.pdf
+!issue15367.pdf
 !issue7446.pdf
 !issue7492.pdf
 !issue7544.pdf

test/unit/api_spec.js

@@ -1535,6 +1535,7 @@ describe("api", function () {
       expect(outline.length).toEqual(6);
 
       expect(outline[4]).toEqual({
+        action: null,
         dest: "Händel -- Halle🎆lujah",
         url: null,
         unsafeUrl: undefined,
@@ -1550,6 +1551,31 @@ describe("api", function () {
       await loadingTask.destroy();
     });
 
+    it("gets outline, with named-actions (issue 15367)", async function () {
+      const loadingTask = getDocument(buildGetDocumentParams("issue15367.pdf"));
+      const pdfDoc = await loadingTask.promise;
+      const outline = await pdfDoc.getOutline();
+
+      expect(Array.isArray(outline)).toEqual(true);
+      expect(outline.length).toEqual(4);
+
+      expect(outline[1]).toEqual({
+        action: "PrevPage",
+        dest: null,
+        url: null,
+        unsafeUrl: undefined,
+        newWindow: undefined,
+        title: "Previous Page",
+        color: new Uint8ClampedArray([0, 0, 0]),
+        count: undefined,
+        bold: false,
+        italic: false,
+        items: [],
+      });
+
+      await loadingTask.destroy();
+    });
+
     it("gets outline with non-displayable chars", async function () {
       const loadingTask = getDocument(buildGetDocumentParams("issue14267.pdf"));
       const pdfDoc = await loadingTask.promise;

web/pdf_outline_viewer.js

@@ -109,13 +109,21 @@ class PDFOutlineViewer extends BaseTreeViewer {
   /**
    * @private
    */
-  _bindLink(element, { url, newWindow, dest }) {
+  _bindLink(element, { url, newWindow, action, dest }) {
     const { linkService } = this;
 
     if (url) {
       linkService.addLinkAttributes(element, url, newWindow);
       return;
     }
+    if (action) {
+      element.href = linkService.getAnchorUrl("");
+      element.onclick = () => {
+        linkService.executeNamedAction(action);
+        return false;
+      };
+      return;
+    }
 
     element.href = linkService.getDestinationHash(dest);
     element.onclick = evt => {