feat: add p/moul/mdtable (#3100)

Can be useful for #3096.

---------

Signed-off-by: moul <94029+moul@users.noreply.github.com>

examples/gno.land/p/moul/mdtable/gno.mod

@@ -0,0 +1,3 @@
+module gno.land/p/moul/mdtable
+
+require gno.land/p/demo/urequire v0.0.0-latest

examples/gno.land/p/moul/mdtable/mdtable.gno

@@ -0,0 +1,66 @@
+// Package mdtable provides a simple way to create Markdown tables.
+//
+// Example usage:
+//
+//	import "gno.land/p/moul/mdtable"
+//
+//	func Render(path string) string {
+//	    table := mdtable.Table{
+//	        Headers: []string{"ID", "Title", "Status", "Date"},
+//	    }
+//	    table.Append([]string{"#1", "Add a new validator", "succeed", "2024-01-01"})
+//	    table.Append([]string{"#2", "Change parameter", "timed out", "2024-01-02"})
+//	    return table.String()
+//	}
+//
+// Output:
+//
+//	| ID | Title | Status | Date |
+//	| --- | --- | --- | --- |
+//	| #1 | Add a new validator | succeed | 2024-01-01 |
+//	| #2 | Change parameter | timed out | 2024-01-02 |
+package mdtable
+
+import (
+	"strings"
+)
+
+type Table struct {
+	Headers []string
+	Rows    [][]string
+	// XXX: optional headers alignment.
+}
+
+func (t *Table) Append(row []string) {
+	t.Rows = append(t.Rows, row)
+}
+
+func (t Table) String() string {
+	// XXX: switch to using text/tabwriter when porting to Gno to support
+	// better-formatted raw Markdown output.
+
+	if len(t.Headers) == 0 && len(t.Rows) == 0 {
+		return ""
+	}
+
+	var sb strings.Builder
+
+	if len(t.Headers) == 0 {
+		t.Headers = make([]string, len(t.Rows[0]))
+	}
+
+	// Print header.
+	sb.WriteString("| " + strings.Join(t.Headers, " | ") + " |\n")
+	sb.WriteString("|" + strings.Repeat(" --- |", len(t.Headers)) + "\n")
+
+	// Print rows.
+	for _, row := range t.Rows {
+		escapedRow := make([]string, len(row))
+		for i, cell := range row {
+			escapedRow[i] = strings.ReplaceAll(cell, "|", "|") // Escape pipe characters.
+		}
+		sb.WriteString("| " + strings.Join(escapedRow, " | ") + " |\n")
+	}
+
+	return sb.String()
+}

examples/gno.land/p/moul/mdtable/mdtable_test.gno

@@ -0,0 +1,158 @@
+package mdtable_test
+
+import (
+	"testing"
+
+	"gno.land/p/demo/urequire"
+	"gno.land/p/moul/mdtable"
+)
+
+// XXX: switch to `func Example() {}` when supported.
+func TestExample(t *testing.T) {
+	table := mdtable.Table{
+		Headers: []string{"ID", "Title", "Status"},
+		Rows: [][]string{
+			{"#1", "Add a new validator", "succeed"},
+			{"#2", "Change parameter", "timed out"},
+			{"#3", "Fill pool", "active"},
+		},
+	}
+
+	got := table.String()
+	expected := `| ID | Title | Status |
+| --- | --- | --- |
+| #1 | Add a new validator | succeed |
+| #2 | Change parameter | timed out |
+| #3 | Fill pool | active |
+`
+
+	urequire.Equal(t, got, expected)
+}
+
+func TestTableString(t *testing.T) {
+	tests := []struct {
+		name     string
+		table    mdtable.Table
+		expected string
+	}{
+		{
+			name: "With Headers and Rows",
+			table: mdtable.Table{
+				Headers: []string{"ID", "Title", "Status", "Date"},
+				Rows: [][]string{
+					{"#1", "Add a new validator", "succeed", "2024-01-01"},
+					{"#2", "Change parameter", "timed out", "2024-01-02"},
+				},
+			},
+			expected: `| ID | Title | Status | Date |
+| --- | --- | --- | --- |
+| #1 | Add a new validator | succeed | 2024-01-01 |
+| #2 | Change parameter | timed out | 2024-01-02 |
+`,
+		},
+		{
+			name: "Without Headers",
+			table: mdtable.Table{
+				Rows: [][]string{
+					{"#1", "Add a new validator", "succeed", "2024-01-01"},
+					{"#2", "Change parameter", "timed out", "2024-01-02"},
+				},
+			},
+			expected: `|  |  |  |  |
+| --- | --- | --- | --- |
+| #1 | Add a new validator | succeed | 2024-01-01 |
+| #2 | Change parameter | timed out | 2024-01-02 |
+`,
+		},
+		{
+			name: "Without Rows",
+			table: mdtable.Table{
+				Headers: []string{"ID", "Title", "Status", "Date"},
+			},
+			expected: `| ID | Title | Status | Date |
+| --- | --- | --- | --- |
+`,
+		},
+		{
+			name: "With Pipe Character in Content",
+			table: mdtable.Table{
+				Headers: []string{"ID", "Title", "Status", "Date"},
+				Rows: [][]string{
+					{"#1", "Add a new | validator", "succeed", "2024-01-01"},
+					{"#2", "Change parameter", "timed out", "2024-01-02"},
+				},
+			},
+			expected: `| ID | Title | Status | Date |
+| --- | --- | --- | --- |
+| #1 | Add a new | validator | succeed | 2024-01-01 |
+| #2 | Change parameter | timed out | 2024-01-02 |
+`,
+		},
+		{
+			name: "With Varying Row Sizes", // XXX: should we have a different behavior?
+			table: mdtable.Table{
+				Headers: []string{"ID", "Title"},
+				Rows: [][]string{
+					{"#1", "Add a new validator"},
+					{"#2", "Change parameter", "Extra Column"},
+					{"#3", "Fill pool"},
+				},
+			},
+			expected: `| ID | Title |
+| --- | --- |
+| #1 | Add a new validator |
+| #2 | Change parameter | Extra Column |
+| #3 | Fill pool |
+`,
+		},
+		{
+			name: "With UTF-8 Characters",
+			table: mdtable.Table{
+				Headers: []string{"ID", "Title", "Status", "Date"},
+				Rows: [][]string{
+					{"#1", "Café", "succeed", "2024-01-01"},
+					{"#2", "München", "timed out", "2024-01-02"},
+					{"#3", "São Paulo", "active", "2024-01-03"},
+				},
+			},
+			expected: `| ID | Title | Status | Date |
+| --- | --- | --- | --- |
+| #1 | Café | succeed | 2024-01-01 |
+| #2 | München | timed out | 2024-01-02 |
+| #3 | São Paulo | active | 2024-01-03 |
+`,
+		},
+		{
+			name:     "With no Headers and no Rows",
+			table:    mdtable.Table{},
+			expected: ``,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := tt.table.String()
+			urequire.Equal(t, got, tt.expected)
+		})
+	}
+}
+
+func TestTableAppend(t *testing.T) {
+	table := mdtable.Table{
+		Headers: []string{"ID", "Title", "Status", "Date"},
+	}
+
+	// Use the Append method to add rows to the table
+	table.Append([]string{"#1", "Add a new validator", "succeed", "2024-01-01"})
+	table.Append([]string{"#2", "Change parameter", "timed out", "2024-01-02"})
+	table.Append([]string{"#3", "Fill pool", "active", "2024-01-03"})
+	got := table.String()
+
+	expected := `| ID | Title | Status | Date |
+| --- | --- | --- | --- |
+| #1 | Add a new validator | succeed | 2024-01-01 |
+| #2 | Change parameter | timed out | 2024-01-02 |
+| #3 | Fill pool | active | 2024-01-03 |
+`
+	urequire.Equal(t, got, expected)
+}