Add editor packages

2026-10-26 02:32:03 +00:00
parent 38714f6c80
commit 4ed2ee97e0
23 changed files with 2114 additions and 0 deletions
@@ -0,0 +1,184 @@
+package buffer
+
+import (
+	"io"
+	"log/slog"
+	"reflect"
+	"testing"
+
+	"code.chimeric.al/dwrz/wen/internal/editor/buffer/line"
+)
+
+func newTestBuffer(lines ...string) *Buffer {
+	var b = &Buffer{
+		cursor: &Cursor{},
+		lines:  make([]*line.Line, 0, len(lines)),
+		log:    slog.New(slog.NewTextHandler(io.Discard, nil)),
+		offset: &offset{},
+	}
+	for _, s := range lines {
+		b.lines = append(b.lines, line.New(s))
+	}
+	if len(b.lines) == 0 {
+		b.lines = append(b.lines, &line.Line{})
+	}
+
+	return b
+}
+
+func bufferLines(b *Buffer) []string {
+	var out = make([]string, len(b.lines))
+	for i, l := range b.lines {
+		out[i] = l.String()
+	}
+
+	return out
+}
+
+type CursorMoveTest struct {
+	lines  []string
+	action func(b *Buffer)
+	want   Cursor
+}
+
+func TestCursorMovement(t *testing.T) {
+	var tests = []CursorMoveTest{
+		{
+			lines:  []string{"ab", "cd"},
+			action: func(b *Buffer) { b.CursorRight() },
+			want:   Cursor{line: 0, index: 1, glyph: 1},
+		},
+		{
+			lines: []string{"a", "b"},
+			action: func(b *Buffer) {
+				b.CursorRight()
+				b.CursorRight()
+			},
+			want: Cursor{line: 1, index: 0, glyph: 0},
+		},
+		{
+			lines: []string{"ab", "cd"},
+			action: func(b *Buffer) {
+				b.CursorDown()
+				b.CursorLeft()
+			},
+			want: Cursor{line: 0, index: 2, glyph: 2},
+		},
+		{
+			lines: []string{"hello", "hi"},
+			action: func(b *Buffer) {
+				b.CursorEnd()
+				b.CursorDown()
+			},
+			want: Cursor{line: 1, index: 2, glyph: 2},
+		},
+		{
+			lines: []string{"abc", "世界"},
+			action: func(b *Buffer) {
+				b.CursorRight()
+				b.CursorDown()
+			},
+			want: Cursor{line: 1, index: 0, glyph: 0},
+		},
+		{
+			lines: []string{"abc", "世界"},
+			action: func(b *Buffer) {
+				b.CursorEnd()
+				b.CursorDown()
+			},
+			want: Cursor{line: 1, index: 3, glyph: 2},
+		},
+	}
+
+	for n, test := range tests {
+		b := newTestBuffer(test.lines...)
+		test.action(b)
+		if got := b.Cursor(); got != test.want {
+			t.Errorf(
+				"#%d: expected cursor %+v, but got %+v",
+				n, test.want, got,
+			)
+		}
+	}
+}
+
+type EditTest struct {
+	lines      []string
+	action     func(b *Buffer)
+	wantLines  []string
+	wantCursor Cursor
+}
+
+func TestEdit(t *testing.T) {
+	var tests = []EditTest{
+		{
+			lines: []string{""},
+			action: func(b *Buffer) {
+				b.Insert('a')
+				b.Insert('世')
+			},
+			wantLines:  []string{"a世"},
+			wantCursor: Cursor{line: 0, index: 4, glyph: 3},
+		},
+		{
+			lines:      []string{"hello"},
+			action:     func(b *Buffer) { b.Newline() },
+			wantLines:  []string{"", "hello"},
+			wantCursor: Cursor{line: 1, index: 0, glyph: 0},
+		},
+		{
+			lines: []string{"abcd"},
+			action: func(b *Buffer) {
+				b.CursorRight()
+				b.CursorRight()
+				b.Newline()
+			},
+			wantLines:  []string{"ab", "cd"},
+			wantCursor: Cursor{line: 1, index: 0, glyph: 0},
+		},
+		{
+			lines: []string{"abcd"},
+			action: func(b *Buffer) {
+				b.CursorEnd()
+				b.Newline()
+			},
+			wantLines:  []string{"abcd", ""},
+			wantCursor: Cursor{line: 1, index: 0, glyph: 0},
+		},
+		{
+			lines: []string{"ab", ""},
+			action: func(b *Buffer) {
+				b.CursorDown()
+				b.Backspace()
+			},
+			wantLines:  []string{"ab"},
+			wantCursor: Cursor{line: 0, index: 2, glyph: 2},
+		},
+		{
+			lines: []string{"ab", "cd"},
+			action: func(b *Buffer) {
+				b.CursorDown()
+				b.Backspace()
+			},
+			wantLines:  []string{"abcd"},
+			wantCursor: Cursor{line: 0, index: 2, glyph: 2},
+		},
+	}
+
+	for n, test := range tests {
+		b := newTestBuffer(test.lines...)
+		test.action(b)
+		if got := bufferLines(b); !reflect.DeepEqual(got, test.wantLines) {
+			t.Errorf(
+				"#%d: expected lines %q, but got %q",
+				n, test.wantLines, got,
+			)
+		}
+		if got := b.Cursor(); got != test.wantCursor {
+			t.Errorf(
+				"#%d: expected cursor %+v, but got %+v",
+				n, test.wantCursor, got,
+			)
+		}
+	}
+}