Vertical AutoMerge keeps unnecessary whitespace when a merged row value is wrapped by WidthMax

[michaelmdresser]

Describe the bug
When using AutoMerge and WidthMax together on a ColumnConfig, unnecessary whitespace is left in rows where the column value is wrapped and has been merged.

To Reproduce

import (
	"fmt"
	"testing"

	"github.com/jedib0t/go-pretty/v6/table"
	"github.com/jedib0t/go-pretty/v6/text"
)

func TestWrapWithVerticalMerge(t *testing.T) {
	tbl := table.NewWriter()

	tbl.SetColumnConfigs([]table.ColumnConfig{
		{
			Name:             "C1",
			AutoMerge:        true,
			WidthMax:         10,
			WidthMaxEnforcer: text.WrapSoft,
		},
		{
			Name: "C2",
		},
	})

	tbl.AppendHeader(table.Row{
		"C1",
		"C2",
	})

	tbl.AppendRows([]table.Row{
		{
			"very long row value that wraps",
			"x",
		},
		{
			"very long row value that wraps",
			"y",
		},
	})

	tblstring := tbl.Render()
	fmt.Println(tblstring)
}

Output:

=== RUN   TestWrapWithVerticalMerge
+------------+----+
| C1         | C2 |
+------------+----+
| very long  | x  |
| row value  |    |
| that wraps |    |
|            | y  |
|            |    |
|            |    |
+------------+----+

Expected behavior
I would expect the output to look more like the following, though I'm open to changes on the specifics. The main point is that, similar to #226, unnecessary space is left because it seems like the merging thinks the original row value (pre merge) is still present.

+------------+----+
| C1         | C2 |
+------------+----+
| very long  | x  |
| row value  | y  |
| that wraps |    |
+------------+----+

Software (please complete the following information):

My go.mod has:

go 1.16

require (
	github.com/jedib0t/go-pretty/v6 v6.4.6
)

• OS: Linux
• GoLang Version: go version go1.20.1 linux/amd64

[jedib0t]

Hey sorry for the late response. This is a known issue, but thanks for bringing it back up. I'll try to spend some time soon to get this fixed.

[thieman]

This would really do wonders for visual clarity on a set of tables I've been working on. Curious whether this is something that should be fairly doable or if it's going to involve big changes to the layout engine. If the former, I might be able to take a look into implementing it.

[jedib0t]

The way the rendering happens now, this is a non-trivial change. I'll try to see if there is a quick way of implementing this.