Merge pull request #1873 from mjf/fix-lua-table-rendering

Fix table cell alignment for missing and misaligned cells

Author: zefhemel

client/markdown_renderer/markdown_render.ts

@@ -421,7 +421,18 @@ function render(
         body: cleanTags(mapRender(t.children!)),
       };
     case "TableRow": {
-      normalizeTableRow(t);
+      const table = t.parent;
+      const header = table?.children?.find((c) => c.type === "TableHeader");
+      let columnCount = 0;
+      let headerHasLeadingDelim: boolean | undefined;
+      if (header) {
+        normalizeTableRow(header);
+        headerHasLeadingDelim = header.children?.[0]?.type === "TableDelimiter";
+        for (const c of header.children ?? []) {
+          if (c.type === "TableCell") columnCount++;
+        }
+      }
+      normalizeTableRow(t, columnCount, headerHasLeadingDelim);
       return {
         name: "tr",
         body: cleanTags(mapRender(t.children!), true),

plug-api/lib/tree.ts

@@ -191,8 +191,14 @@ export function nodeAtPos(tree: ParseTree, pos: number): ParseTree | null {
   return null;
 }
 
-// Ensure a TableRow has a TableCell between every pair of TableDelimiters
-export function normalizeTableRow(row: ParseTree): void {
+// Ensure a TableRow/TableHeader has a TableCell between every pair of
+// TableDelimiters, and optionally pad to match columnCount.
+// headerHasLeadingDelim indicates whether the header starts with a delimiter.
+export function normalizeTableRow(
+  row: ParseTree,
+  columnCount?: number,
+  headerHasLeadingDelim?: boolean,
+): void {
   const children = row.children;
   if (!children) return;
   const normalized: ParseTree[] = [];
@@ -210,6 +216,26 @@ export function normalizeTableRow(row: ParseTree): void {
     normalized.push(child);
   }
   row.children = normalized;
+
+  // Fix leading-pipe mismatch: row has leading delimiter but header doesn't
+  if (headerHasLeadingDelim === false) {
+    if (row.children.length > 0 && row.children[0].type === "TableDelimiter") {
+      // Insert empty cell after the leading delimiter
+      row.children.splice(1, 0, { type: "TableCell", children: [] });
+    }
+  }
+
+  // Pad trailing empty cells to match header column count
+  if (columnCount !== undefined) {
+    let cellCount = 0;
+    for (const child of row.children) {
+      if (child.type === "TableCell") cellCount++;
+    }
+    while (cellCount < columnCount) {
+      row.children.push({ type: "TableCell", children: [] });
+      cellCount++;
+    }
+  }
 }
 
 // Turn ParseTree back into text

plugs/index/table.ts

@@ -63,20 +63,21 @@ export function indexTables(
   ).forEach(
     (table) => {
       const rows = collectNodesOfType(table, "TableRow");
-      const header = collectNodesOfType(table, "TableHeader")[0]; //Use first header. As per markdown spec there can only be exactly one
+      const header = collectNodesOfType(table, "TableHeader")[0];
+      normalizeTableRow(header);
+      const headerHasLeadingDelim =
+        header.children?.[0]?.type === "TableDelimiter";
       const headerLabels = collectNodesOfType(header, "TableCell").map((cell) =>
         concatChildrenTexts(cell.children!)
       ).map(cleanHeaderFieldName);
-      //console.log("Header labels", headerLabels);
 
       for (const row of rows) {
         const tags = new Set<string>();
         collectNodesOfType(row, "Hashtag").forEach((h) => {
-          // Push tag to the list, removing the initial #
           tags.add(extractHashtag(h.children![0].text!));
         });
 
-        normalizeTableRow(row);
+        normalizeTableRow(row, headerLabels.length, headerHasLeadingDelim);
 
         const cells = collectNodesOfType(row, "TableCell");