[#578] Add binding for AcroFormDocumentHelper::setFormFieldName method

src/core/acroform.cpp

@@ -0,0 +1,50 @@
+// SPDX-FileCopyrightText: 2022 James R. Barlow
+// SPDX-License-Identifier: MPL-2.0
+
+#include <qpdf/QPDFAcroFormDocumentHelper.hh>
+
+#include <pybind11/pybind11.h>
+#include <pybind11/stl.h>
+
+#include "pikepdf.h"
+
+void init_acroform(py::module_ &m)
+{
+    py::class_<QPDFAcroFormDocumentHelper,
+        std::shared_ptr<QPDFAcroFormDocumentHelper>,
+        QPDFDocumentHelper>(m, "AcroFormDocument")
+        .def(
+            py::init([](QPDF &q) {
+                QPDFAcroFormDocumentHelper afdh(q);
+
+                return afdh;
+            }),
+            py::keep_alive<0, 1>(), // LCOV_EXCL_LINE
+            py::arg("q")
+        )
+        .def(
+            "set_form_field_name",
+            [](QPDFAcroFormDocumentHelper &afdh, QPDFObjectHandle annot, std::string const& name) {
+                QPDFFormFieldObjectHelper ffh = afdh.getFieldForAnnotation(annot);
+                auto ffh_oh = ffh.getObjectHandle();
+                if (ffh_oh.hasKey("/Parent")) {
+                    QPDFObjectHandle parent = ffh_oh.getKey("/Parent");
+                    QPDFFormFieldObjectHelper ph(parent);
+                    afdh.setFormFieldName(ph, name);
+                } else {
+                    afdh.setFormFieldName(ffh, name);
+                }
+            }
+        )
+        .def(
+            "get_form_fields",
+            [](QPDFAcroFormDocumentHelper &afdh) {
+                return afdh.getFormFields();
+            },
+            py::return_value_policy::reference_internal
+        );
+
+    py::class_<QPDFFormFieldObjectHelper,
+        std::shared_ptr<QPDFFormFieldObjectHelper>,
+        QPDFObjectHelper>(m, "FormField");
+}

src/core/object.cpp

@@ -14,6 +14,7 @@
 #include <qpdf/QPDFObjectHandle.hh>
 #include <qpdf/QPDF.hh>
 #include <qpdf/QPDFWriter.hh>
+#include <qpdf/QPDFDocumentHelper.hh>
 
 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>
@@ -895,6 +896,18 @@ void init_object(py::module_ &m)
         .def_property_readonly("obj", [](QPDFObjectHelper &poh) -> QPDFObjectHandle {
             return poh.getObjectHandle();
         });
+    py::class_<QPDFDocumentHelper, std::shared_ptr<QPDFDocumentHelper>>(m, "DocumentHelper");
+//        .def(
+//            "__eq__",
+//            [](QPDFObjectHelper &self, QPDFObjectHelper &other) {
+//                // Object helpers are equal if their object handles are equal
+//                return objecthandle_equal(
+//                    self.getObjectHandle(), other.getObjectHandle());
+//            },
+//            py::is_operator())
+//        .def_property_readonly("obj", [](QPDFObjectHelper &poh) -> QPDFObjectHandle {
+//            return poh.getObjectHandle();
+//        });
 
     m.def("_encode", [](py::handle handle) { return objecthandle_encode(handle); });
     m.def("unparse", [](py::object obj) -> py::bytes {

src/core/pikepdf.cpp

@@ -126,6 +126,7 @@ PYBIND11_MODULE(_core, m)
     init_job(m);
 
     // -- Support objects (alphabetize order) --
+    init_acroform(m);
     init_annotation(m);
     init_embeddedfiles(m);
     init_matrix(m);

src/core/pikepdf.h

@@ -133,6 +133,8 @@ QPDFObjectHandle objecthandle_encode(const py::handle handle);
 std::vector<QPDFObjectHandle> array_builder(const py::iterable iter);
 std::map<std::string, QPDFObjectHandle> dict_builder(const py::dict dict);
 
+// From acroform.cpp
+void init_acroform(py::module_ &m);
 // From annotation.cpp
 void init_annotation(py::module_ &m);
 // From embeddedfiles.cpp

src/pikepdf/__init__.py

@@ -17,6 +17,7 @@
 
 from pikepdf._core import (
     AccessMode,
+    AcroFormDocument,
     Annotation,
     AttachedFileSpec,
     ContentStreamInlineImage,
@@ -90,6 +91,7 @@
 
 __all__ = [
     'AccessMode',
+    'AcroFormDocument',
     'Annotation',
     'AttachedFileSpec',
     'ContentStreamInlineImage',

src/pikepdf/_core.pyi

@@ -523,6 +523,10 @@ class ObjectHelper:
     def obj(self) -> Dictionary:
         """Get the underlying PDF object (typically a Dictionary)."""
 
+class DocumentHelper:
+    """Base class for wrapper/helper around a Document.
+    """
+
 class _ObjectList:
     """A list whose elements are always pikepdf.Object.
 
@@ -684,6 +688,19 @@ class AttachedFile:
     def size(self) -> int:
         """Get length of the attached file in bytes according to the PDF creator."""
 
+class AcroFormDocument(DocumentHelper):
+    def __init__(
+        self
+    ) -> None:
+        """Construct an AcroFormDocumentHelper.
+        """
+    def set_form_field_name(self, annot: Object, name: str) -> None:
+        """Set form field name
+        """
+    def get_form_fields(self) -> list[ObjectHelper]:
+        """Get form fields
+        """
+
 class AttachedFileSpec(ObjectHelper):
     r"""In a PDF, a file specification provides name and metadata for a target file.
 

tests/test_acroform.py

@@ -0,0 +1,26 @@
+# SPDX-FileCopyrightText: 2022 James R. Barlow
+# SPDX-License-Identifier: CC0-1.0
+
+from __future__ import annotations
+
+import pytest
+
+from pikepdf import AcroFormDocument, Pdf
+
+
+@pytest.fixture
+def form(resources):
+    with Pdf.open(resources / 'form.pdf') as pdf:
+        yield pdf
+
+
+def test_set_form_field_name(form):
+    afd = AcroFormDocument(form)
+    field = form.Root.AcroForm.Fields[0]
+    assert field.T == 'Text1'
+    afd.set_form_field_name(field, 'new_field_name')
+    assert field.T == 'new_field_name'
+
+def test_get_form_fields(form):
+    afd = AcroFormDocument(form)
+    assert len(afd.get_form_fields()) == 4