FPDF.table() now raises an error when a single row is too high to be …

…rendered on a single page

CHANGELOG.md

@@ -23,6 +23,7 @@ This can also be enabled programmatically with `warnings.simplefilter('default',
 * [`fpdf.drawing.DeviceCMYK`](https://py-pdf.github.io/fpdf2/fpdf/drawing.html#fpdf.drawing.DeviceCMYK) objects can now be passed to [`FPDF.set_draw_color()`](https://py-pdf.github.io/fpdf2/fpdf/fpdf.html#fpdf.fpdf.FPDF.set_draw_color), [`FPDF.set_fill_color()`](https://py-pdf.github.io/fpdf2/fpdf/fpdf.html#fpdf.fpdf.FPDF.set_fill_color) and [`FPDF.set_text_color()`](https://py-pdf.github.io/fpdf2/fpdf/fpdf.html#fpdf.fpdf.FPDF.set_text_color) without raising a `ValueError`: [documentation](https://py-pdf.github.io/fpdf2/Text.html#text-formatting).
 
 ### Changed
+* [`FPDF.table()`](https://py-pdf.github.io/fpdf2/Tables.html) now raises an error when a single row is too high to be rendered on a single page
 
 ### Deprecated
 

fpdf/fpdf.py

@@ -3402,7 +3402,7 @@ def will_page_break(self, height):
         """
         return (
             # ensure that there is already some content on the page:
-            self.y > self.t_margin
+            self.y >= self.t_margin
             and self.y + height > self.page_break_trigger
             and not self.in_footer
             and self.accept_page_break

fpdf/table.py

@@ -189,7 +189,7 @@ def render(self):
                     )
 
         # Defining table global horizontal position:
-        prev_l_margin = self._fpdf.l_margin
+        prev_x, prev_y, prev_l_margin = self._fpdf.x, self._fpdf.y, self._fpdf.l_margin
         if table_align == Align.C:
             self._fpdf.l_margin = (self._fpdf.w - self._width) / 2
             self._fpdf.x = self._fpdf.l_margin
@@ -220,10 +220,20 @@ def render(self):
         )
         self._fpdf.y += self._outer_border_margin[1]
         for i, row in enumerate(self.rows):
+            pagebreak_height = row_info[i].pagebreak_height
             # pylint: disable=protected-access
-            page_break = self._fpdf._perform_page_break_if_need_be(
-                row_info[i].pagebreak_height
-            )
+            page_break = self._fpdf._perform_page_break_if_need_be(pagebreak_height)
+            if (
+                page_break
+                and self._fpdf.y + pagebreak_height > self._fpdf.page_break_trigger
+            ):
+                # Restoring original position on page:
+                self._fpdf.x = prev_x
+                self._fpdf.y = prev_y
+                self._fpdf.l_margin = prev_l_margin
+                raise ValueError(
+                    f"The row with index {i} is too high and cannot be rendered on a single page"
+                )
             if page_break and repeat_headings and i >= self._num_heading_rows:
                 # repeat headings on top:
                 self._fpdf.y += self._outer_border_margin[1]
@@ -372,9 +382,8 @@ def _render_table_cell(
 
         # place cursor (required for images after images)
 
-        if (
-            height_query_only
-        ):  # not rendering, cell_x_positions is not relevant (and probably not provided)
+        # not rendering, cell_x_positions is not relevant (and probably not provided):
+        if height_query_only:
             cell_x = 0
         else:
             cell_x = cell_x_positions[j]
@@ -483,7 +492,7 @@ def _render_table_cell(
             dy = 0
 
             if cell_height is not None:
-                actual_text_height = cell_height_info.rendered_height[j]
+                actual_text_height = cell_height_info.rendered_heights[j]
 
                 if v_align == VAlign.M:
                     dy = (cell_height - actual_text_height) / 2
@@ -848,8 +857,10 @@ def write(self, text, align=None):
 @dataclass(frozen=True)
 class RowLayoutInfo:
     height: float
+    # accumulated rowspans to take in account when considering page breaks:
     pagebreak_height: float
-    rendered_height: dict
+    # heights of every cell in the row:
+    rendered_heights: dict
     merged_heights: list
 
 

test/table/test_table.py

@@ -802,3 +802,30 @@ def test_table_cell_fill_mode(tmp_path):
             pass
         pdf.ln()
     assert_pdf_equal(pdf, HERE / "table_cell_fill_mode.pdf", tmp_path)
+
+
+def test_table_with_very_long_text():
+    pdf = FPDF()
+    pdf.add_page()
+    pdf.set_font("Helvetica")
+    with pytest.raises(ValueError) as error:
+        with pdf.table() as table:
+            row = table.row()
+            row.cell(LOREM_IPSUM)
+            # Adding columns to have the content of the 1st cell to overflow:
+            row.cell("")
+            row.cell("")
+    assert (
+        str(error.value)
+        == "The row with index 0 is too high and cannot be rendered on a single page"
+    )
+    with pytest.raises(ValueError) as error:
+        with pdf.table() as table:
+            row = table.row()
+            row.cell("")
+            row.cell("")
+            row.cell(LOREM_IPSUM)
+    assert (
+        str(error.value)
+        == "The row with index 0 is too high and cannot be rendered on a single page"
+    )

test/table/test_table_rowspan.py

@@ -168,9 +168,6 @@ def test_table_with_rowspan_and_pgbreak(tmp_path):
     ]
 
     pdf.add_page()
-    y0 = pdf.h - pdf.b_margin
-    with pdf.local_context(**line_opts):
-        pdf.line(0, y0, pdf.w, y0)
 
     # simple table
     # with pdf.table(TABLE_DATA, **table_opts):
@@ -181,7 +178,9 @@ def test_table_with_rowspan_and_pgbreak(tmp_path):
     # -- verify break occurs before the offending rowspan
     # -- verify header reproduction
     pdf.set_y(pdf.h - 85)
+    y0 = pdf.h - pdf.b_margin
     with pdf.local_context(**line_opts):
+        pdf.line(0, y0, pdf.w, y0)
         pdf.line(0, pdf.y, pdf.w, pdf.y)
     with pdf.table(TABLE_DATA, **table_opts):
         pass