fix(runtime): align table columns by terminal display width

go.mod

@@ -5,6 +5,7 @@ go 1.25.13
 require (
 	github.com/gofrs/flock v0.13.1
 	github.com/lathe-cli/kitup/go v0.1.3
+	github.com/rivo/uniseg v0.4.7
 	github.com/santhosh-tekuri/jsonschema/v6 v6.0.3
 	github.com/spf13/cobra v1.10.2
 	github.com/spf13/pflag v1.0.10

go.sum

@@ -20,6 +20,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/lathe-cli/kitup/go v0.1.3 h1:7eEW8mDr5MbXFaTwr2dlnH8ebg+3Kmhj2/j4d9YfQNQ=
 github.com/lathe-cli/kitup/go v0.1.3/go.mod h1:dZgJDmFRKjaFBZyaP1qlzOB9IEafnf1/ai4KX4hMA4c=
+github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
+github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/santhosh-tekuri/jsonschema/v6 v6.0.3 h1:1EYB5IzjZawrrnELUi78f9fPu57HuXjmddZPjrls/28=
 github.com/santhosh-tekuri/jsonschema/v6 v6.0.3/go.mod h1:JXeL+ps8p7/KNMjDQk3TCwPpBy0wYklyWTfbkIzdIFU=

pkg/runtime/formatter_test.go

@@ -2,6 +2,8 @@ package runtime
 
 import (
 	"bytes"
+	"encoding/json"
+	"errors"
 	"io"
 	"strings"
 	"testing"
@@ -99,6 +101,75 @@ func TestFormatOutput_TableUsesConfiguredColumnLabels(t *testing.T) {
 	}
 }
 
+func TestFormatOutput_TableAlignsDisplayColumns(t *testing.T) {
+	cells := []struct {
+		text  string
+		width int
+	}{
+		{"abcd", 4},
+		{"勿删", 4},
+		{"ＡＢ", 4},
+		{"東京", 4},
+		{"한글", 4},
+		{"e\u0301", 1},
+		{"🇨🇳", 2},
+		{"👩‍💻", 2},
+		{"勿删-测试", 9},
+		{"", 0},
+	}
+	rows := make([]map[string]string, len(cells))
+	for i, cell := range cells {
+		rows[i] = map[string]string{"name": cell.text, "status": "ok"}
+	}
+	rows = append(rows, map[string]string{"status": "ok"})
+	data, err := json.Marshal(rows)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, header := range []struct {
+		text  string
+		width int
+	}{
+		{"NAME", 4},
+		{"资源显示名称", 12},
+	} {
+		for _, format := range []string{"", "table"} {
+			t.Run(header.text+"/"+format, func(t *testing.T) {
+				var buf bytes.Buffer
+				err := FormatOutput(data, format, &buf, OutputHints{
+					DefaultColumns: []string{"name", "status"},
+					ColumnLabels:   map[string]string{"name": header.text},
+				})
+				if err != nil {
+					t.Fatal(err)
+				}
+				columnWidth := max(9, header.width)
+				want := header.text + strings.Repeat(" ", columnWidth-header.width+2) + "STATUS\n"
+				for _, cell := range cells {
+					want += cell.text + strings.Repeat(" ", columnWidth-cell.width+2) + "ok\n"
+				}
+				want += strings.Repeat(" ", columnWidth+2) + "ok\n"
+				if buf.String() != want {
+					t.Fatalf("table columns are misaligned:\ngot  %q\nwant %q", buf.String(), want)
+				}
+			})
+		}
+	}
+}
+
+func TestFormatOutput_TableWriterError(t *testing.T) {
+	reader, writer := io.Pipe()
+	defer func() { _ = writer.Close() }()
+	want := errors.New("output unavailable")
+	if err := reader.CloseWithError(want); err != nil {
+		t.Fatal(err)
+	}
+	err := FormatOutput([]byte(`[{"name":"勿删"}]`), "table", writer, OutputHints{})
+	if !errors.Is(err, want) {
+		t.Fatalf("FormatOutput error = %v, want %v", err, want)
+	}
+}
+
 func TestFormatOutput_TableUsesExactCurrencyFormats(t *testing.T) {
 	var buf bytes.Buffer
 	data := []byte(`{"items":[{"amount":1000000},{"amount":1234567},{"amount":1},{"amount":-5000000},{"amount":9007199254740993},{"amount":"2500000"},{"amount":1.25}]}`)

pkg/runtime/table.go

@@ -6,7 +6,8 @@ import (
 	"io"
 	"sort"
 	"strings"
-	"text/tabwriter"
+
+	"github.com/rivo/uniseg"
 )
 
 // PreferredColumns is the canonical ordering used both by codegen (to derive
@@ -240,24 +241,39 @@ func stringify(v any) string {
 }
 
 func writeTable(cols []string, rows []map[string]any, labels map[string]string, formats map[string]ColumnFormat, w io.Writer) error {
-	tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', 0)
-	for i, c := range cols {
-		if i > 0 {
-			fmt.Fprint(tw, "\t")
+	type cell struct {
+		text  string
+		width int
+	}
+	cells := make([]cell, (len(rows)+1)*len(cols))
+	widths := make([]int, len(cols))
+	for row := range len(rows) + 1 {
+		for col, path := range cols {
+			value := &cells[row*len(cols)+col]
+			if row == 0 {
+				value.text = columnHeader(path, labels)
+			} else {
+				value.text = lookupPath(rows[row-1], path, formats)
+			}
+			if col < len(cols)-1 {
+				value.width = uniseg.StringWidth(value.text)
+				widths[col] = max(widths[col], value.width)
+			}
 		}
-		fmt.Fprint(tw, columnHeader(c, labels))
 	}
-	fmt.Fprintln(tw)
-	for _, r := range rows {
-		for i, c := range cols {
-			if i > 0 {
-				fmt.Fprint(tw, "\t")
+	var output strings.Builder
+	for row := range len(rows) + 1 {
+		for col := range cols {
+			value := cells[row*len(cols)+col]
+			output.WriteString(value.text)
+			if col < len(cols)-1 {
+				output.WriteString(strings.Repeat(" ", widths[col]-value.width+2))
 			}
-			fmt.Fprint(tw, lookupPath(r, c, formats))
 		}
-		fmt.Fprintln(tw)
+		output.WriteByte('\n')
 	}
-	return tw.Flush()
+	_, err := io.WriteString(w, output.String())
+	return err
 }
 
 func columnHeader(path string, labels map[string]string) string {