Start writing tests for readline internal functions

tools/tui/readline/actions.go

@@ -11,6 +11,42 @@ import (
 
 var _ = fmt.Print
 
+func (self *Readline) text_upto_cursor_pos() string {
+	buf := strings.Builder{}
+	buf.Grow(1024)
+	for i, line := range self.lines {
+		if i == self.cursor_line {
+			buf.WriteString(line[:self.cursor_pos_in_line])
+			break
+		} else {
+			buf.WriteString(line)
+			buf.WriteString("\n")
+		}
+	}
+	return buf.String()
+}
+
+func (self *Readline) text_after_cursor_pos() string {
+	buf := strings.Builder{}
+	buf.Grow(1024)
+	for i, line := range self.lines {
+		if i == self.cursor_line {
+			buf.WriteString(line[self.cursor_pos_in_line:])
+			buf.WriteString("\n")
+		} else if i > self.cursor_line {
+			buf.WriteString(line)
+			buf.WriteString("\n")
+		}
+	}
+	ans := buf.String()
+	ans = ans[:len(ans)-1]
+	return ans
+}
+
+func (self *Readline) all_text() string {
+	return strings.Join(self.lines, "\n")
+}
+
 func (self *Readline) add_text(text string) {
 	new_lines := make([]string, 0, len(self.lines)+4)
 	new_lines = append(new_lines, self.lines[:self.cursor_line]...)

tools/tui/readline/actions_test.go

@@ -0,0 +1,41 @@
+// License: GPLv3 Copyright: 2022, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package readline
+
+import (
+	"fmt"
+	"kitty/tools/tui/loop"
+	"testing"
+)
+
+var _ = fmt.Print
+
+func TestAddText(t *testing.T) {
+	lp, _ := loop.New()
+
+	dt := func(initial string, prepare func(rl *Readline), expected ...string) {
+		rl := New(lp, RlInit{})
+		rl.add_text(initial)
+		if prepare != nil {
+			prepare(rl)
+		}
+		if len(expected) > 0 {
+			if expected[0] != rl.text_upto_cursor_pos() {
+				t.Fatalf("Text upto cursor pos not as expected for: %#v\n%#v != %#v", initial, expected[0], rl.text_upto_cursor_pos())
+			}
+		}
+		if len(expected) > 1 {
+			if expected[1] != rl.text_after_cursor_pos() {
+				t.Fatalf("Text after cursor pos not as expected for: %#v\n%#v != %#v", initial, expected[1], rl.text_after_cursor_pos())
+			}
+		}
+		if len(expected) > 2 {
+			if expected[2] != rl.all_text() {
+				t.Fatalf("Text not as expected for: %#v\n%#v != %#v", initial, expected[2], rl.all_text())
+			}
+		}
+	}
+
+	dt("test", nil, "test", "", "test")
+
+}