Marmelator/pdf.js.mirror
1
0
Fork 0
mirror of https://github.com/mozilla/pdf.js.git synced 2026-07-25 16:37:22 +02:00
Code Issues Packages Projects Releases Wiki Activity

Handle indirect and dangling structure tree root kids

Browse Source 
Preserve indirect root kids and marked content from removed link annotations. Ignore dangling kid references instead of throwing.
This commit is contained in:
Calixte Denizet 2026-07-13 11:02:08 +02:00
parent b19cc7c746
commit dae773d74a
2 changed files with 126 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
src/core/editor/pdf_editor.js
View File

@ -530,6 +530,14 @@ class PDFEditor {
return ref;
}
async #resolveStructKids(rawKids, xref) {
if (rawKids instanceof Ref) {
const fetched = await xref.fetchAsync(rawKids);
return Array.isArray(fetched) ? fetched : [rawKids];
}
return Array.isArray(rawKids) ? rawKids : [rawKids];
}
async #cloneStructTreeNode(
parentStructRef,
node,
@ -547,19 +555,11 @@ class PDFEditor {
if (pg instanceof Ref && !pagesMap.has(pg)) {
return null;
}
let kids;
const k = (kids = node.getRaw("K"));
if (k instanceof Ref) {
// We're only interested by ref referencing nodes and not an array.
if (visited.has(k)) {
return null;
}
kids = await xref.fetchAsync(k);
if (!Array.isArray(kids)) {
kids = [k];
}
const k = node.getRaw("K");
if (k instanceof Ref && visited.has(k)) {
return null;
}
kids = Array.isArray(kids) ? kids : [kids];
const kids = await this.#resolveStructKids(k, xref);
const newKids = [];
const structElemIndices = [];
for (let kid of kids) {
@ -1523,17 +1523,24 @@ class PDFEditor {
}
// Get the kids.
let kids = structTreeRoot.dict.get("K");
if (!kids) {
const rawKids = structTreeRoot.dict.getRaw("K");
if (!rawKids) {
continue;
}
kids = Array.isArray(kids) ? kids : [kids];
const kids = await this.#resolveStructKids(rawKids, xref);
for (let kid of kids) {
const kidRef = kid instanceof Ref ? kid : null;
if (kidRef && removedStructElements.has(kidRef)) {
kid = await xref.fetchIfRefAsync(kid);
if (!(kid instanceof Dict)) {
continue;
}
kid = await xref.fetchIfRefAsync(kid);
let setAsSpan = false;
if (kidRef && removedStructElements.has(kidRef)) {
if (!isName(kid.get("S"), "Link")) {
continue;
}
setAsSpan = true;
}
const newKidRef = await this.#cloneStructTreeNode(
kidRef,
kid,
@ -1545,6 +1552,12 @@ class PDFEditor {
);
if (newKidRef) {
structTreeKids.push(newKidRef);
if (kidRef) {
oldRefMapping.put(kidRef, newKidRef);
}
if (setAsSpan) {
this.xref[newKidRef.num].setIfName("S", "Span");
}
}
}

96
test/unit/api_spec.js
View File

@ -6622,6 +6622,102 @@ small scripts as well as for`);
});
describe("Struct trees", function () {
it("preserves an indirect StructTreeRoot kid", async function () {
const objects = [
"1 0 obj\n<< /Type /Catalog /Pages 2 0 R " +
"/StructTreeRoot 4 0 R >>\nendobj\n",
"2 0 obj\n<< /Type /Pages /Kids [3 0 R] /Count 1 >>\nendobj\n",
"3 0 obj\n<< /Type /Page /Parent 2 0 R /StructParents 0 " +
"/MediaBox [0 0 100 100] >>\nendobj\n",
"4 0 obj\n<< /Type /StructTreeRoot /K 5 0 R " +
"/ParentTree 6 0 R /ParentTreeNextKey 1 >>\nendobj\n",
"5 0 obj\n<< /Type /StructElem /S /P /P 4 0 R /Pg 3 0 R " +
"/K 0 >>\nendobj\n",
"6 0 obj\n<< /Nums [0 [5 0 R]] >>\nendobj\n",
];
let loadingTask = getDocument({ data: assemblePdf(objects) });
let pdfDoc = await loadingTask.promise;
let page = await pdfDoc.getPage(1);
expect((await page.getStructTree()).children[0].role).toEqual("P");
const data = await pdfDoc.extractPages([{ document: null }]);
await loadingTask.destroy();
loadingTask = getDocument({ data });
pdfDoc = await loadingTask.promise;
page = await pdfDoc.getPage(1);
const tree = await page.getStructTree();
expect(tree.children.length).toEqual(1);
expect(tree.children[0].role).toEqual("P");
expect(tree.children[0].children[0].type).toEqual("content");
await loadingTask.destroy();
});
it("extracts pages when the StructTreeRoot /K is dangling", async function () {
const objects = [
"1 0 obj\n<< /Type /Catalog /Pages 2 0 R " +
"/StructTreeRoot 4 0 R >>\nendobj\n",
"2 0 obj\n<< /Type /Pages /Kids [3 0 R] /Count 1 >>\nendobj\n",
"3 0 obj\n<< /Type /Page /Parent 2 0 R " +
"/MediaBox [0 0 100 100] >>\nendobj\n",
"4 0 obj\n<< /Type /StructTreeRoot /K 99 0 R >>\nendobj\n",
];
let loadingTask = getDocument({ data: assemblePdf(objects) });
let pdfDoc = await loadingTask.promise;
const data = await pdfDoc.extractPages([{ document: null }]);
expect(data).not.toBeNull();
await loadingTask.destroy();
loadingTask = getDocument({ data });
pdfDoc = await loadingTask.promise;
expect(pdfDoc.numPages).toEqual(1);
const page = await pdfDoc.getPage(1);
expect((await page.getStructTree())?.children.length ?? 0).toEqual(0);
await loadingTask.destroy();
});
it("preserves a root Link when its annotation is removed", async function () {
const objects = [
"1 0 obj\n<< /Type /Catalog /Pages 2 0 R " +
"/StructTreeRoot 6 0 R >>\nendobj\n",
"2 0 obj\n<< /Type /Pages /Kids [3 0 R 4 0 R] " +
"/Count 2 >>\nendobj\n",
"3 0 obj\n<< /Type /Page /Parent 2 0 R /StructParents 0 " +
"/Annots [5 0 R] /MediaBox [0 0 100 100] >>\nendobj\n",
"4 0 obj\n<< /Type /Page /Parent 2 0 R " +
"/MediaBox [0 0 100 100] >>\nendobj\n",
"5 0 obj\n<< /Type /Annot /Subtype /Link /Rect [0 0 10 10] " +
"/StructParent 1 /Dest [4 0 R /Fit] >>\nendobj\n",
"6 0 obj\n<< /Type /StructTreeRoot /K 7 0 R " +
"/ParentTree 8 0 R /ParentTreeNextKey 2 >>\nendobj\n",
"7 0 obj\n<< /Type /StructElem /S /Link /P 6 0 R /Pg 3 0 R " +
"/K 0 >>\nendobj\n",
"8 0 obj\n<< /Nums [0 [7 0 R] 1 7 0 R] >>\nendobj\n",
];
let loadingTask = getDocument({ data: assemblePdf(objects) });
let pdfDoc = await loadingTask.promise;
let page = await pdfDoc.getPage(1);
expect((await page.getStructTree()).children[0].role).toEqual("Link");
const data = await pdfDoc.extractPages([
{ document: null, excludePages: [1] },
]);
await loadingTask.destroy();
loadingTask = getDocument({ data });
pdfDoc = await loadingTask.promise;
expect(pdfDoc.numPages).toEqual(1);
page = await pdfDoc.getPage(1);
expect((await page.getAnnotations()).length).toEqual(0);
const tree = await page.getStructTree();
expect(tree.children.length).toEqual(1);
expect(tree.children[0].role).toEqual("Span");
expect(tree.children[0].children[0].type).toEqual("content");
await loadingTask.destroy();
});
it("extract pages and merge struct trees", async function () {
let loadingTask = getDocument(
buildGetDocumentParams("two_paragraphs.pdf")