add column width to TableCell nodes

commonmark-ext-gfm-tables/src/main/java/org/commonmark/ext/gfm/tables/TableCell.java

@@ -9,6 +9,7 @@ public class TableCell extends CustomNode {
 
     private boolean header;
     private Alignment alignment;
+    private int width;
 
     /**
      * @return whether the cell is a header or not
@@ -32,6 +33,17 @@ public void setAlignment(Alignment alignment) {
         this.alignment = alignment;
     }
 
+    /**
+     * @return the cell width (the number of dash and colon characters in the delimiter row of the table for this column)
+     */
+    public int getWidth() {
+        return width;
+    }
+
+    public void setWidth(int width) {
+        this.width = width;
+    }
+
     /**
      * How the cell is aligned horizontally.
      */

commonmark-ext-gfm-tables/src/main/java/org/commonmark/ext/gfm/tables/internal/TableBlockParser.java

@@ -17,11 +17,11 @@ public class TableBlockParser extends AbstractBlockParser {
 
     private final TableBlock block = new TableBlock();
     private final List<SourceLine> rowLines = new ArrayList<>();
-    private final List<TableCell.Alignment> columns;
+    private final List<TableCellInfo> columns;
 
     private boolean canHaveLazyContinuationLines = true;
 
-    private TableBlockParser(List<TableCell.Alignment> columns, SourceLine headerLine) {
+    private TableBlockParser(List<TableCellInfo> columns, SourceLine headerLine) {
         this.columns = columns;
         this.rowLines.add(headerLine);
     }
@@ -120,7 +120,9 @@ private TableCell parseCell(SourceLine cell, int column, InlineParser inlinePars
         }
 
         if (column < columns.size()) {
-            tableCell.setAlignment(columns.get(column));
+            TableCellInfo cellInfo = columns.get(column);
+            tableCell.setAlignment(cellInfo.getAlignment());
+            tableCell.setWidth(cellInfo.getWidth());
         }
 
         CharSequence content = cell.getContent();
@@ -187,11 +189,12 @@ private static List<SourceLine> split(SourceLine line) {
     // -|-
     // |-|-|
     // --- | ---
-    private static List<TableCell.Alignment> parseSeparator(CharSequence s) {
-        List<TableCell.Alignment> columns = new ArrayList<>();
+    private static List<TableCellInfo> parseSeparator(CharSequence s) {
+        List<TableCellInfo> columns = new ArrayList<>();
         int pipes = 0;
         boolean valid = false;
         int i = 0;
+        int width = 0;
         while (i < s.length()) {
             char c = s.charAt(i);
             switch (c) {
@@ -216,10 +219,12 @@ private static List<TableCell.Alignment> parseSeparator(CharSequence s) {
                     if (c == ':') {
                         left = true;
                         i++;
+                        width++;
                     }
                     boolean haveDash = false;
                     while (i < s.length() && s.charAt(i) == '-') {
                         i++;
+                        width++;
                         haveDash = true;
                     }
                     if (!haveDash) {
@@ -229,8 +234,10 @@ private static List<TableCell.Alignment> parseSeparator(CharSequence s) {
                     if (i < s.length() && s.charAt(i) == ':') {
                         right = true;
                         i++;
+                        width++;
                     }
-                    columns.add(getAlignment(left, right));
+                    columns.add(new TableCellInfo(getAlignment(left, right), width));
+                    width = 0;
                     // Next, need another pipe
                     pipes = 0;
                     break;
@@ -270,7 +277,7 @@ public BlockStart tryStart(ParserState state, MatchedBlockParser matchedBlockPar
             if (paragraphLines.size() == 1 && Parsing.find('|', paragraphLines.get(0).getContent(), 0) != -1) {
                 SourceLine line = state.getLine();
                 SourceLine separatorLine = line.substring(state.getIndex(), line.getContent().length());
-                List<TableCell.Alignment> columns = parseSeparator(separatorLine.getContent());
+                List<TableCellInfo> columns = parseSeparator(separatorLine.getContent());
                 if (columns != null && !columns.isEmpty()) {
                     SourceLine paragraph = paragraphLines.get(0);
                     List<SourceLine> headerCells = split(paragraph);
@@ -284,4 +291,22 @@ public BlockStart tryStart(ParserState state, MatchedBlockParser matchedBlockPar
             return BlockStart.none();
         }
     }
+
+    private static class TableCellInfo {
+        private final TableCell.Alignment alignment;
+        private final int width;
+
+        public TableCell.Alignment getAlignment() {
+            return alignment;
+        }
+
+        public int getWidth() {
+            return width;
+        }
+
+        public TableCellInfo(TableCell.Alignment alignment, int width) {
+            this.alignment = alignment;
+            this.width = width;
+        }
+    }
 }

commonmark-ext-gfm-tables/src/test/java/org/commonmark/ext/gfm/tables/TablesTest.java

@@ -749,6 +749,42 @@ public void setAttributes(Node node, String tagName, Map<String, String> attribu
                 "</table>\n"));
     }
 
+    @Test
+    public void columnWidthIsRecorded() {
+        AttributeProviderFactory factory = new AttributeProviderFactory() {
+            @Override
+            public AttributeProvider create(AttributeProviderContext context) {
+                return new AttributeProvider() {
+                    @Override
+                    public void setAttributes(Node node, String tagName, Map<String, String> attributes) {
+                        if (node instanceof TableCell && "th".equals(tagName)) {
+                            attributes.put("width", ((TableCell) node).getWidth() + "em");
+                        }
+                    }
+                };
+            }
+        };
+        HtmlRenderer renderer = HtmlRenderer.builder()
+                .attributeProviderFactory(factory)
+                .extensions(EXTENSIONS)
+                .build();
+        String rendered = renderer.render(PARSER.parse("Abc|Def\n-----|---\n1|2"));
+        assertThat(rendered, is("<table>\n" +
+                "<thead>\n" +
+                "<tr>\n" +
+                "<th width=\"5em\">Abc</th>\n" +
+                "<th width=\"3em\">Def</th>\n" +
+                "</tr>\n" +
+                "</thead>\n" +
+                "<tbody>\n" +
+                "<tr>\n" +
+                "<td>1</td>\n" +
+                "<td>2</td>\n" +
+                "</tr>\n" +
+                "</tbody>\n" +
+                "</table>\n"));
+    }
+
     @Test
     public void sourceSpans() {
         Parser parser = Parser.builder()