Read complete prompt input lines

interact/read_long_line_test.go

@@ -0,0 +1,89 @@
+package interact_test
+
+import (
+	"errors"
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/gookit/cliui"
+	"github.com/gookit/cliui/interact"
+	"github.com/gookit/goutil/x/assert"
+)
+
+func TestReadLineReturnsCompletePhysicalLine(t *testing.T) {
+	for _, tc := range []struct{ name, input, want string }{
+		{"long ASCII", strings.Repeat("a", 12000) + "\nnext\n", strings.Repeat("a", 12000)},
+		{"long Unicode", strings.Repeat("αβ.", 3000) + "\nnext\n", strings.Repeat("αβ.", 3000)},
+		{"buffer boundary", strings.Repeat("b", 4096) + "\nnext\n", strings.Repeat("b", 4096)},
+		{"CRLF and trim", "  " + strings.Repeat("c", 9000) + "  \r\nnext\n", strings.Repeat("c", 9000)},
+		{"short line", " first \nnext\n", "first"},
+		{"empty line", "\nnext\n", ""},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			cliui.CustomIO(strings.NewReader(tc.input), io.Discard)
+			defer cliui.ResetIO()
+			got, err := interact.ReadLine("")
+			assert.NoErr(t, err)
+			assert.Eq(t, tc.want, got)
+			got, err = interact.ReadLine("")
+			assert.NoErr(t, err)
+			assert.Eq(t, "next", got)
+			_, err = interact.ReadLine("")
+			if !errors.Is(err, io.EOF) {
+				t.Fatalf("final error=%v,want EOF", err)
+			}
+		})
+	}
+	t.Run("unterminated final line", func(t *testing.T) {
+		want := strings.Repeat("d", 12000)
+		cliui.CustomIO(strings.NewReader(want), io.Discard)
+		defer cliui.ResetIO()
+		got, err := interact.ReadLine("")
+		assert.NoErr(t, err)
+		assert.Eq(t, want, got)
+		_, err = interact.ReadLine("")
+		if !errors.Is(err, io.EOF) {
+			t.Fatalf("final error=%v,want EOF", err)
+		}
+	})
+}
+
+func TestReadLineExactBufferFinalLine(t *testing.T) {
+	for _, tc := range []struct{ name, line string }{
+		{"4096 ASCII", strings.Repeat("a", 4096)},
+		{"8192 ASCII", strings.Repeat("b", 8192)},
+		{"4096 UTF8", strings.Repeat("α", 2048)},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			cliui.CustomIO(strings.NewReader(tc.line), io.Discard)
+			defer cliui.ResetIO()
+			got, err := interact.ReadLine("")
+			assert.NoErr(t, err)
+			assert.Eq(t, tc.line, got)
+			got, err = interact.ReadLine("")
+			if got != "" || !errors.Is(err, io.EOF) {
+				t.Fatalf("next read=%q,%v;want empty and EOF", got, err)
+			}
+		})
+	}
+}
+
+func TestReadLinePreservesNonEOFErrorAfterFragments(t *testing.T) {
+	reader, writer := io.Pipe()
+	defer reader.Close()
+	failure := errors.New("input stream failed")
+	done := make(chan struct{})
+	go func() {
+		defer close(done)
+		_, _ = io.WriteString(writer, strings.Repeat("x", 4096))
+		_ = writer.CloseWithError(failure)
+	}()
+	cliui.CustomIO(reader, io.Discard)
+	defer cliui.ResetIO()
+	got, err := interact.ReadLine("")
+	<-done
+	if len(got) != 4096 || !errors.Is(err, failure) {
+		t.Fatalf("read bytes=%d,error=%v;want4096bytes and actual stream failure", len(got), err)
+	}
+}

internal/util.go

@@ -49,6 +49,16 @@ func ReadLineWithOutput(question string, out io.Writer) (string, error) {
 		color.Fprint(out, question)
 	}
 
-	answer, _, err := inputReader(cutypes.Input).ReadLine()
-	return strings.TrimSpace(string(answer)), err
+	reader := inputReader(cutypes.Input)
+	var answer []byte
+	for {
+		part, prefix, err := reader.ReadLine()
+		answer = append(answer, part...)
+		if err != nil || !prefix {
+			if err == io.EOF && len(answer) > 0 {
+				err = nil
+			}
+			return strings.TrimSpace(string(answer)), err
+		}
+	}
 }