fix: Handle panic in ReadKey()

internal/core/keys.go

@@ -264,17 +264,38 @@ func (k *Keys) ReadKey() (key rune, isAbort bool) {
 		k.mutex.RUnlock()
 	}()
 
-	switch {
-	case len(k.macroKeys) > 0:
-		key = k.macroKeys[0]
-		k.macroKeys = k.macroKeys[1:]
+	for {
+		switch {
+		case len(k.macroKeys) > 0:
+			key = k.macroKeys[0]
+			k.macroKeys = k.macroKeys[1:]
+		case k.waiting:
+			buf := <-k.keysOnce
+			if len(buf) == 0 {
+				if k.eof {
+					return 0, true
+				}
+				continue
+			}
+			key = []rune(string(buf))[0]
+		default:
+			buf, err := k.readInputFiltered()
+			if err != nil {
+				if errors.Is(err, io.EOF) {
+					k.eof = true
+				}
+				return 0, true
+			}
+			if len(buf) == 0 {
+				if k.eof {
+					return 0, true
+				}
+				continue
+			}
+			key = []rune(string(buf))[0]
+		}
 
-	case k.waiting:
-		buf := <-k.keysOnce
-		key = []rune(string(buf))[0]
-	default:
-		buf, _ := k.readInputFiltered()
-		key = []rune(string(buf))[0]
+		break
 	}
 
 	// Always mark those keys as matched, so that

internal/core/keys_test.go

@@ -0,0 +1,82 @@
+package core
+
+import (
+	"io"
+	"testing"
+)
+
+type readStep struct {
+	data []byte
+	err  error
+}
+
+type stubReadCloser struct {
+	steps []readStep
+	index int
+}
+
+func (s *stubReadCloser) Read(p []byte) (int, error) {
+	if s.index >= len(s.steps) {
+		return 0, io.EOF
+	}
+
+	step := s.steps[s.index]
+	s.index++
+
+	copy(p, step.data)
+
+	return len(step.data), step.err
+}
+
+func (s *stubReadCloser) Close() error {
+	return nil
+}
+
+func TestKeysReadKeySkipsEmptyReads(t *testing.T) {
+	originalStdin := Stdin
+	Stdin = &stubReadCloser{
+		steps: []readStep{
+			{},
+			{data: []byte("x")},
+		},
+	}
+	t.Cleanup(func() {
+		Stdin = originalStdin
+	})
+
+	keys := &Keys{}
+
+	key, isAbort := keys.ReadKey()
+
+	if isAbort {
+		t.Fatal("expected ReadKey to continue after an empty read")
+	}
+
+	if key != 'x' {
+		t.Fatalf("expected key %q, got %q", 'x', key)
+	}
+}
+
+func TestKeysReadKeyReturnsAbortOnEOF(t *testing.T) {
+	originalStdin := Stdin
+	Stdin = &stubReadCloser{
+		steps: []readStep{
+			{err: io.EOF},
+		},
+	}
+	t.Cleanup(func() {
+		Stdin = originalStdin
+	})
+
+	keys := &Keys{}
+
+	key, isAbort := keys.ReadKey()
+
+	if !isAbort {
+		t.Fatal("expected ReadKey to abort on EOF")
+	}
+
+	if key != 0 {
+		t.Fatalf("expected zero key on EOF, got %q", key)
+	}
+}