fix(xlsx): fill table cells to the full line height with Excel insets

crates/office2pdf/src/parser/xlsx.rs

@@ -369,7 +369,7 @@ impl XlsxParser {
                                 column_widths: ctx.column_widths.clone(),
                                 header_row_count,
                                 alignment: None,
-                                default_cell_padding: None,
+                                default_cell_padding: Some(xlsx_cells::XLSX_CELL_PADDING),
                                 use_content_driven_row_heights: false,
                                 default_vertical_align: Some(crate::ir::CellVerticalAlign::Bottom),
                             },
@@ -548,7 +548,7 @@ impl Parser for XlsxParser {
                                 column_widths: ctx.column_widths,
                                 header_row_count,
                                 alignment: None,
-                                default_cell_padding: None,
+                                default_cell_padding: Some(xlsx_cells::XLSX_CELL_PADDING),
                                 use_content_driven_row_heights: false,
                                 default_vertical_align: Some(crate::ir::CellVerticalAlign::Bottom),
                             },
@@ -616,7 +616,7 @@ impl Parser for XlsxParser {
                                     column_widths: ctx.column_widths.clone(),
                                     header_row_count: segment_header_rows,
                                     alignment: None,
-                                    default_cell_padding: None,
+                                    default_cell_padding: Some(xlsx_cells::XLSX_CELL_PADDING),
                                     use_content_driven_row_heights: false,
                                     default_vertical_align: Some(
                                         crate::ir::CellVerticalAlign::Bottom,

crates/office2pdf/src/parser/xlsx_cells.rs

@@ -486,6 +486,17 @@ fn compute_spill_width(
 /// Excel's fallback row height when the sheet declares none (Calibri 11).
 const EXCEL_DEFAULT_ROW_HEIGHT_PT: f64 = 15.0;
 
+/// Cell insets for spreadsheet tables. Excel pads cells only slightly
+/// above/below the text; Typst's default 5pt vertical inset overflowed
+/// auto-height rows (issue #396). Horizontal inset keeps ~2pt/side, the
+/// value the column-spill estimate assumes.
+pub(super) const XLSX_CELL_PADDING: crate::ir::Insets = crate::ir::Insets {
+    top: 1.0,
+    right: 2.0,
+    bottom: 1.0,
+    left: 2.0,
+};
+
 /// The height a row prints at. A recorded `ht` is the actual current height
 /// even when `customHeight` is false; rows without one use the sheet's
 /// defaultRowHeight. Exception: auto-sized rows (customHeight=false) that

crates/office2pdf/src/render/typst_gen_table_cell_content_tests.rs

@@ -242,18 +242,21 @@ fn test_table_cell_compact_list_adds_inter_item_spacing_from_line_spacing() {
 #[test]
 fn test_east_asian_table_cell_uses_natural_line_height_not_grid() {
     // Word does not snap table-cell text to the document grid (measured
-    // Korean cells sit at the font's full line, not a grid multiple), so
-    // cells must use the natural single-spacing line height rather than
-    // Typst's glyph-tight default (issue #385). Uses a Typst-embedded font
-    // so the test is environment-free.
+    // Korean cells sit at the font's full line, not a grid multiple), and a
+    // single-line cell occupies the whole hhea line — emitted as a fixed
+    // box split by the ascender/descender ratio with zero leading, so
+    // auto-height rows are not left short (issues #385, #396). Uses a
+    // Typst-embedded font so the test is environment-free.
     let Some((ascender, descender, word_pitch_em)) =
         crate::render::pdf::font_line_metrics_em("Libertinus Serif")
     else {
         return; // no font book available (e.g. exotic CI sandbox)
     };
     let font_size: f64 = 10.0;
-    let natural_leading = ((word_pitch_em - (ascender + descender)) * font_size).max(0.0);
-    let grid_leading = 18.0 - (ascender + descender) * font_size;
+    let metric_em: f64 = ascender + descender;
+    let top_em: f64 = word_pitch_em * ascender / metric_em;
+    let bottom_em: f64 = word_pitch_em * descender / metric_em;
+    let grid_leading = 18.0 - metric_em * font_size;
     let cell = TableCell {
         content: vec![Block::Paragraph(Paragraph {
             style: ParagraphStyle::default(),
@@ -290,14 +293,14 @@ fn test_east_asian_table_cell_uses_natural_line_height_not_grid() {
     assert!(
         result.contains(&format!(
             "top-edge: {}em, bottom-edge: -{}em",
-            format_f64(ascender),
-            format_f64(descender)
+            format_f64(top_em),
+            format_f64(bottom_em)
         )),
-        "Korean cell must use fixed nominal-metric em edges: {result}"
+        "Korean cell must fill the full hhea line box: {result}"
     );
     assert!(
-        result.contains(&format!("leading: {}pt", format_f64(natural_leading))),
-        "Korean cell must use natural single-spacing leading ({natural_leading}pt): {result}"
+        result.contains("#set par(leading: 0pt)"),
+        "cell line box uses zero leading (box already equals the full line): {result}"
     );
     assert!(
         !result.contains(&format!("leading: {}pt", format_f64(grid_leading))),
@@ -307,16 +310,18 @@ fn test_east_asian_table_cell_uses_natural_line_height_not_grid() {
 
 #[test]
 fn test_latin_table_cell_uses_natural_line_height() {
-    // Latin cells likewise use their metric single-spacing line height
-    // (Word single spacing = hhea line), not Typst's glyph-tight default
-    // (issue #385).
+    // Latin cells likewise fill the font's full hhea line box (Word single
+    // spacing = hhea line), not Typst's glyph-tight default (issues #385,
+    // #396).
     let Some((ascender, descender, word_pitch_em)) =
         crate::render::pdf::font_line_metrics_em("Libertinus Serif")
     else {
         return;
     };
     let font_size: f64 = 10.0;
-    let natural_leading = ((word_pitch_em - (ascender + descender)) * font_size).max(0.0);
+    let metric_em: f64 = ascender + descender;
+    let top_em: f64 = word_pitch_em * ascender / metric_em;
+    let bottom_em: f64 = word_pitch_em * descender / metric_em;
     let cell = TableCell {
         content: vec![Block::Paragraph(Paragraph {
             style: ParagraphStyle::default(),
@@ -344,7 +349,11 @@ fn test_latin_table_cell_uses_natural_line_height() {
     let doc = make_doc(vec![make_flow_page(vec![Block::Table(table)])]);
     let result = generate_typst(&doc).unwrap().source;
     assert!(
-        result.contains(&format!("leading: {}pt", format_f64(natural_leading))),
-        "Latin cell must use natural single-spacing leading ({natural_leading}pt): {result}"
+        result.contains(&format!(
+            "top-edge: {}em, bottom-edge: -{}em",
+            format_f64(top_em),
+            format_f64(bottom_em)
+        )),
+        "Latin cell must fill the full hhea line box: {result}"
     );
 }

crates/office2pdf/src/render/typst_gen_tables.rs

@@ -540,13 +540,13 @@ fn generate_cell_paragraph(out: &mut String, para: &Paragraph, default_tab_width
         Some(Alignment::Right) => Some("right"),
         _ => None,
     };
-    // Table-cell text keeps its natural single-spacing line height: Word
-    // does not snap cell content to the section's document grid (measured
-    // Korean cells sit at the font's full line, not a grid multiple), so
-    // cells rendered with Typst's glyph-tight default came out shorter than
-    // Word's rows (issue #385). Passing no grid pitch selects the metric
-    // edges plus hhea leading, matching body text without the grid snap.
-    let line_height_settings: Option<String> = word_line_height_settings(&para.runs, style, None);
+    // Table-cell text occupies the font's full single-spacing (hhea) line
+    // as a fixed box: Word does not snap cell content to the document grid
+    // (measured Korean cells sit at the font's full line, not a grid
+    // multiple, issue #385), and a single-line cell must fill the whole
+    // line height Word gives it rather than only the tighter metric box —
+    // otherwise auto-height rows come out short (issue #396).
+    let line_height_settings: Option<String> = word_cell_line_box_settings(&para.runs, style);
     let has_block_wrapper = cell_paragraph_needs_block_wrapper(style)
         || align_str.is_some()
         || line_height_settings.is_some();

crates/office2pdf/src/render/typst_gen_text.rs

@@ -165,6 +165,34 @@ fn word_line_box_and_leading(
     Some((ascender_em, descender_em, leading_pt))
 }
 
+/// Line-box settings for a table cell: a fixed box spanning the font's
+/// full single-spacing (hhea) line, split by the ascender/descender ratio,
+/// with zero leading. A single-line cell then occupies the whole line
+/// height Word gives it, rather than only the tighter metric box (which
+/// left auto-height rows too short, issue #396). `None` when the font's
+/// metrics are unknown or the paragraph carries its own line spacing/box.
+pub(super) fn word_cell_line_box_settings(runs: &[Run], style: &ParagraphStyle) -> Option<String> {
+    if style.line_spacing.is_some() || style.line_box.is_some() {
+        return None;
+    }
+    let family: &str = runs
+        .iter()
+        .find_map(|run| run.style.font_family.as_deref())?;
+    let (ascender_em, descender_em, word_pitch_em) =
+        crate::render::pdf::font_line_metrics_em(family)?;
+    let metric_em: f64 = ascender_em + descender_em;
+    if metric_em <= 0.0 || word_pitch_em <= 0.0 {
+        return None;
+    }
+    let top_em: f64 = word_pitch_em * ascender_em / metric_em;
+    let bottom_em: f64 = word_pitch_em * descender_em / metric_em;
+    Some(format!(
+        "#set text(top-edge: {}em, bottom-edge: -{}em)\n#set par(leading: 0pt)\n",
+        format_f64(top_em),
+        format_f64(bottom_em)
+    ))
+}
+
 /// The leading that accompanies Word metric text edges: the whitespace
 /// Typst must insert between metric line boxes so consecutive lines land at
 /// Word's single-space advance (or the document grid pitch). `None` when

crates/office2pdf/tests/xlsx_fixtures.rs

@@ -310,11 +310,13 @@ fn acceptance_pr_186_contributor_acceptance_double_border_rendering() {
     let output = generate_typst(&document).expect("fixture should generate Typst");
 
     assert!(!output.source.contains("dash: \"dashed\""));
+    // Overlay offsets track the cell padding; XLSX cells use ~2pt insets so
+    // Excel auto-rows are not overflowed (issue #396).
     assert!(output.source.contains(
-        "#place(top + left, dx: -5pt, dy: -6pt, line(length: 100% + 10pt, angle: 0deg, stroke: 1pt + rgb(0, 0, 0)))"
+        "#place(top + left, dx: -2pt, dy: -2pt, line(length: 100% + 4pt, angle: 0deg, stroke: 1pt + rgb(0, 0, 0)))"
     ));
     assert!(output.source.contains(
-        "#place(top + left, dx: -5pt, dy: -4pt, line(length: 100% + 10pt, angle: 0deg, stroke: 1pt + rgb(0, 0, 0)))"
+        "#place(top + left, dx: -2pt, dy: 0pt, line(length: 100% + 4pt, angle: 0deg, stroke: 1pt + rgb(0, 0, 0)))"
     ));
 }