add hexai-tmux-edit: tmux popup editor for AI agent prompts

New tool that opens $EDITOR in a tmux popup for composing longer prompts
when working with AI CLI agents (Claude Code, Cursor, Amp, Aider, etc.).
Captures existing prompt text from the target pane, pre-fills the editor,
and sends edited text back via tmux send-keys. Config-driven agent
detection via regex patterns in [tmux_edit] config section.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/internal/tmuxedit/capture_test.go b/internal/tmuxedit/capture_test.go
new file mode 100644
index 0000000..40d0e98
--- /dev/null
+++ b/internal/tmuxedit/capture_test.go
@@ -0,0 +1,51 @@
+package tmuxedit
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestCapturePane_Success(t *testing.T) {
+	old := runCommand
+	defer func() { runCommand = old }()
+	runCommand = func(name string, args ...string) ([]byte, error) {
+		if name == "tmux" && len(args) >= 3 && args[0] == "capture-pane" {
+			return []byte("Claude Code v1.0\n> hello world\n"), nil
+		}
+		return nil, fmt.Errorf("unexpected: %s %v", name, args)
+	}
+	got, err := capturePane("%5")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if got != "Claude Code v1.0\n> hello world" {
+		t.Errorf("got %q, want trimmed content", got)
+	}
+}
+
+func TestCapturePane_Error(t *testing.T) {
+	old := runCommand
+	defer func() { runCommand = old }()
+	runCommand = func(string, ...string) ([]byte, error) {
+		return nil, fmt.Errorf("pane not found")
+	}
+	_, err := capturePane("%999")
+	if err == nil {
+		t.Fatal("expected error for failed capture")
+	}
+}
+
+func TestCapturePane_EmptyContent(t *testing.T) {
+	old := runCommand
+	defer func() { runCommand = old }()
+	runCommand = func(string, ...string) ([]byte, error) {
+		return []byte("\n\n"), nil
+	}
+	got, err := capturePane("%1")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if got != "" {
+		t.Errorf("got %q, want empty string", got)
+	}
+}