ENH: Add ability to add hex encoded colors to outline items

PyPDF2/_writer.py

@@ -1164,7 +1164,7 @@ def add_outline_item(
         title: str,
         pagenum: int,
         parent: Union[None, TreeObject, IndirectObject] = None,
-        color: Optional[Tuple[float, float, float]] = None,
+        color: Optional[Union[Tuple[float, float, float], str]] = None,
         bold: bool = False,
         italic: bool = False,
         fit: FitType = "/Fit",
@@ -1178,7 +1178,7 @@ def add_outline_item(
         :param parent: A reference to a parent outline item to create nested
             outline items.
         :param tuple color: Color of the outline item's font as a red, green, blue tuple
-            from 0.0 to 1.0
+            from 0.0 to 1.0 or as a Hex String (#RRGGBB)
         :param bool bold: Outline item font is bold
         :param bool italic: Outline item font is italic
         :param str fit: The fit of the destination page. See

PyPDF2/generic.py

@@ -2017,30 +2017,29 @@ def create_string_object(
 def _create_outline_item(
     action_ref: IndirectObject,
     title: str,
-    color: Optional[Tuple[float, float, float]],
+    color: Union[Tuple[float, float, float], str, None],
     italic: bool,
     bold: bool,
 ) -> TreeObject:
     outline_item = TreeObject()
-
     outline_item.update(
         {
             NameObject("/A"): action_ref,
             NameObject("/Title"): create_string_object(title),
         }
     )
-
-    if color is not None:
+    if color:
+        if isinstance(color, str):
+            color = hex_to_rgb(color)
         outline_item.update(
             {NameObject("/C"): ArrayObject([FloatObject(c) for c in color])}
         )
-
-    format_flag = 0
-    if italic:
-        format_flag += 1
-    if bold:
-        format_flag += 2
-    if format_flag:
+    if italic or bold:
+        format_flag = 0
+        if italic:
+            format_flag += 1
+        if bold:
+            format_flag += 2
         outline_item.update({NameObject("/F"): NumberObject(format_flag)})
     return outline_item
 
@@ -2074,7 +2073,7 @@ def decode_pdfdocencoding(byte_array: bytes) -> str:
 
 
 def hex_to_rgb(value: str) -> Tuple[float, float, float]:
-    return tuple(int(value[i : i + 2], 16) / 255.0 for i in (0, 2, 4))  # type: ignore
+    return tuple(int(value.lstrip("#")[i : i + 2], 16) / 255.0 for i in (0, 2, 4))  # type: ignore
 
 
 class AnnotationBuilder:

tests/test_writer.py

@@ -13,6 +13,7 @@
 TESTS_ROOT = Path(__file__).parent.resolve()
 PROJECT_ROOT = TESTS_ROOT.parent
 RESOURCE_ROOT = PROJECT_ROOT / "resources"
+EXTERNAL_ROOT = Path(PROJECT_ROOT) / "sample-files"
 
 
 def test_writer_clone():
@@ -633,3 +634,25 @@ def test_deprecate_bookmark_decorator():
         match="bookmark is deprecated as an argument. Use outline_item instead",
     ):
         writer.add_outline_item_dict(bookmark=outline_item)
+
+
+def test_colors_in_outline_item():
+    reader = PdfReader(EXTERNAL_ROOT / "004-pdflatex-4-pages/pdflatex-4-pages.pdf")
+    writer = PdfWriter()
+    writer.clone_document_from_reader(reader)
+    purple_rgb = (0.50196, 0, 0.50196)
+    writer.add_outline_item("First Outline Item", pagenum=2, color="800080")
+    writer.add_outline_item("Second Outline Item", pagenum=3, color="#800080")
+    writer.add_outline_item("Third Outline Item", pagenum=4, color=purple_rgb)
+
+    target = "tmp-named-color-outline.pdf"
+    with open(target, "wb") as f:
+        writer.write(f)
+
+    reader2 = PdfReader(target)
+    for outline_item in reader2.outline:
+        # convert float to string because of mutability
+        assert [str(c) for c in outline_item.color] == [str(p) for p in purple_rgb]
+
+    # Cleanup
+    os.remove(target)  # remove for testing