Support for colspan in tables

[hughdavenport]

For a project I'm working on, having colspan would be useful, like described at github/markup#1151

Basically would want something like this to be able to be generated. I've opened a support ticket with GFM to see whether it could be added to the spec.

<table>
    <tr><th colspan=2>Logical Operators</th></tr>
    <tr><td>&&</td><td>Logical and</td></tr>
    <tr><td>||</td><td>Logical or</td></tr>
    <tr><td>!</td><td>Logical not</td></tr>
    <tr><td>? :</td><td>Logical ternary</td></tr>
</table>

Perhaps the syntax could be something like (using |- as a separator that is spanning, which would then ignore that contents?):

| Logical Operators  |-|
|:---:| --- |
| && | Logical and      |
| \|\|  | Logical or         |
| !     | Logical not       |
| ? :  | Logical ternary |

[hughdavenport]

I've made PR #11 for this.

[hughdavenport]

If support is needed now, this is what I use:

def check_commonmark_tables_bug10():

    class RendererWaitingForBug10(commonmark_extensions.tables.RendererWithTables):
        def table(self, node, entering):
            if entering:
                self.lit(self.make_table_node(node) + "\n")
                for i, part in enumerate(node.table):
                    if i == 0:
                        part_tag = "thead"
                    else:
                        part_tag = "tbody"
                    self.lit("<" + part_tag + ">\n")
                    for row in part:
                        self.lit("<tr>\n")
                        for colidx, cell in enumerate(row):
                            if cell.first_child and cell.first_child.literal == '-':
                                continue
                            if part_tag == "thead":
                                col_tag = "th"
                                if self.options.get("table_th_scope"):
                                    col_attrs = '  scope="col"'
                                else:
                                    col_attrs = ''
                            else:
                                col_tag = "td"
                                col_attrs = ""

                            if colidx in node.column_properties and "align" in node.column_properties[colidx]:
                                col_attrs += ' align=\"' + node.column_properties[colidx]["align"] + "\""

                            span = 1
                            for nextid in range(colidx+1, len(row)):
                                if row[nextid].first_child and row[nextid].first_child.literal == '-':
                                    span += 1
                                else:
                                    break
                            if span > 1:
                                col_attrs += ' colspan=\"' + str(span) + '\"'

                            self.lit("<" + col_tag + col_attrs + ">")

                            import copy
                            inner_renderer = copy.copy(self)
                            cell = inner_renderer.render(cell)

                            # If the cell is just one <p>, unwrap it.
                            m = re.match("<p>(.*)</p>$", cell)
                            if m:
                                cell = m.group(1)

                            self.lit(cell)
                            self.lit("</" + col_tag + ">\n")
                        self.lit("</tr>\n")
                    self.lit("</" + part_tag + ">\n")
                self.lit("</table>\n")

    parser = commonmark_extensions.tables.ParserWithTables()
    renderer = commonmark_extensions.tables.RendererWithTables()
    example_with_cols = """| foo | -   |
| --- | --- |
| bar | baz |"""
    example_with_cols_expected = "".join("""<table>
<thead>
<tr>
<th colspan="2">foo</th>
</tr>
</thead>
<tbody>
<tr>
<td>bar</td>
<td>baz</td>
</tr>
</tbody>
</table>""".split())

    if "".join(renderer.render(parser.parse(example_with_cols)).split()) != example_with_cols_expected:
        eprint("Missing update for commonmark_extensions (bug #10),",
                "applying monkeypatch")
        return RendererWaitingForBug10()
    return renderer

renderer = check_commonmark_tables_bug10()
# use renderer as normal