fix(pptx): convert soft line breaks instead of emitting a vertical tab

packages/markitdown/src/markitdown/converters/_pptx_converter.py

@@ -31,6 +31,18 @@
 ACCEPTED_FILE_EXTENSIONS = [".pptx"]
 
 
+def _normalize_soft_line_breaks(text: str) -> str:
+    """Turn the soft line breaks python-pptx reports into newlines.
+
+    A soft line break (Shift+Enter) is an ``<a:br/>`` inside one paragraph, and
+    python-pptx renders it as a vertical tab. A vertical tab is not Markdown: it
+    is a C0 control that renderers drop and that nothing downstream treats as
+    whitespace, so the lines on either side of it run together. The paragraphs
+    of a shape already arrive joined with newlines, so use the same separator.
+    """
+    return text.replace("\v", "\n")
+
+
 class PptxConverter(DocumentConverter):
     """
     Converts PPTX files to Markdown. Supports heading, tables and images with alt text.
@@ -105,10 +117,12 @@ def get_shape_content(shape, **kwargs):
 
                 # Text areas
                 elif shape.has_text_frame:
-                    text = shape.text or ""
+                    text = _normalize_soft_line_breaks(shape.text or "")
                     if shape == title:
                         if text.strip():
-                            md_content += "# " + text.lstrip() + "\n"
+                            # An ATX heading cannot span lines: a newline would
+                            # close the heading and leave the rest as body text.
+                            md_content += "# " + text.replace("\n", " ").strip() + "\n"
                     else:
                         md_content += text + "\n"
 
@@ -141,7 +155,11 @@ def get_shape_content(shape, **kwargs):
                 # has merely been opened, so having one says nothing about there
                 # being notes to read. Only head a section that has content.
                 notes_frame = slide.notes_slide.notes_text_frame
-                notes_text = (notes_frame.text or "") if notes_frame is not None else ""
+                notes_text = (
+                    _normalize_soft_line_breaks(notes_frame.text or "")
+                    if notes_frame is not None
+                    else ""
+                )
                 if notes_text.strip():
                     md_content += "\n\n### Notes:\n" + notes_text
                     md_content = md_content.strip()
@@ -309,10 +327,11 @@ def _convert_table_to_markdown(self, table, **kwargs):
         for row in table.rows:
             html_table += "<tr>"
             for cell in row.cells:
+                cell_text = html.escape(_normalize_soft_line_breaks(cell.text))
                 if first_row:
-                    html_table += "<th>" + html.escape(cell.text) + "</th>"
+                    html_table += "<th>" + cell_text + "</th>"
                 else:
-                    html_table += "<td>" + html.escape(cell.text) + "</td>"
+                    html_table += "<td>" + cell_text + "</td>"
             html_table += "</tr>"
             first_row = False
         html_table += "</table></body></html>"
@@ -330,7 +349,7 @@ def _convert_chart_to_markdown(self, chart):
             # None. has_text_frame is the property that actually reflects
             # whether a text frame exists.
             if chart.has_title and chart.chart_title.has_text_frame:
-                md += f": {chart.chart_title.text_frame.text}"
+                md += f": {_normalize_soft_line_breaks(chart.chart_title.text_frame.text)}"
             md += "\n\n"
             data = []
             category_names = [c.label for c in chart.plots[0].categories]

packages/markitdown/tests/test_pptx.py

@@ -770,6 +770,49 @@ def test_missing_optional_dependencies_fail_before_hook(
 # Conversion regressions
 
 
+def test_pptx_soft_line_breaks_are_not_vertical_tabs() -> None:
+    """A soft line break must not reach the Markdown as a vertical tab.
+
+    Shift+Enter inside a PowerPoint paragraph is an ``<a:br/>``, which python-pptx
+    reports as ``\v``. A vertical tab is a C0 control, not Markdown: a renderer
+    drops it, so the lines on either side run together, and nothing downstream
+    treats it as whitespace either.
+    """
+    presentation = Presentation()
+    slide = presentation.slides.add_slide(presentation.slide_layouts[5])
+    slide.shapes.title.text = "TITLE ONE\vTITLE TWO"
+
+    text_box = slide.shapes.add_textbox(Inches(0.5), Inches(2), Inches(4), Inches(1))
+    text_box.text_frame.text = "ADDRESS LINE ONE\vADDRESS LINE TWO"
+
+    table = slide.shapes.add_table(
+        2, 2, Inches(0.5), Inches(3.5), Inches(6), Inches(1.5)
+    ).table
+    table.cell(0, 0).text = "HEADER A\vHEADER B"
+    table.cell(0, 1).text = "H2"
+    table.cell(1, 0).text = "CELL LINE ONE\vCELL LINE TWO"
+    table.cell(1, 1).text = "C2"
+
+    slide.notes_slide.notes_text_frame.text = "NOTE LINE ONE\vNOTE LINE TWO"
+
+    buffer = io.BytesIO()
+    presentation.save(buffer)
+    buffer.seek(0)
+
+    md = MarkItDown().convert_stream(buffer, file_extension=".pptx").markdown
+
+    assert "\v" not in md
+    # A shape's own paragraphs are joined with newlines, so a soft break reads
+    # the same way.
+    assert "ADDRESS LINE ONE\nADDRESS LINE TWO" in md
+    assert "NOTE LINE ONE\nNOTE LINE TWO" in md
+    # A heading and a table row cannot carry a newline, so those collapse to a
+    # space and the row stays one row.
+    assert "# TITLE ONE TITLE TWO" in md
+    assert "| CELL LINE ONE CELL LINE TWO | C2 |" in md
+    assert "| HEADER A HEADER B | H2 |" in md
+
+
 def test_pptx_chart_multi_series_conversion() -> None:
     """Charts with multiple series and many categories must convert correctly.