Reject an empty argument list in execute_lua

`lua.execute` with no arguments dereferenced `args.begin()`.

src/command_scheduler.cc

@@ -28,9 +28,10 @@ cmd_scheduler_simple_removed(core::Download* download) {
   control->core()->download_list()->pause(download);
 
   core::View* viewActive = *control->view_manager()->find("active");
+  unsigned int numActive = viewActive->size_visible();
   int64_t maxActive = rpc::call_command("scheduler.max_active", torrent::Object()).as_value();
 
-  if ((int64_t)viewActive->size_visible() >= maxActive)
+  if ((int64_t)numActive >= maxActive)
     return torrent::Object();
 
   // The 'started' view contains all the views we may choose amongst.
@@ -41,6 +42,9 @@ cmd_scheduler_simple_removed(core::Download* download) {
       continue;
 
     control->core()->download_list()->resume(*itr);
+
+    if ((int64_t)++numActive >= maxActive)
+      break;
   }
 
   return torrent::Object();

src/input/path_input.cc

@@ -100,7 +100,7 @@ PathInput::receive_do_complete() {
       entry.s_name += '/';
   }
 
-  range_type r = find_incomplete(dir, str().substr(dirEnd, get_pos()));
+  range_type r = find_incomplete(dir, str().substr(dirEnd, get_pos() - dirEnd));
 
   if (r.first == r.second)
     return; // Show some nice colors here.

src/main.cc

@@ -492,7 +492,8 @@ main(int argc, char** argv) {
     control->cleanup();
 
   } catch (torrent::internal_error& e) {
-    control->cleanup_exception();
+    if (control != nullptr)
+      control->cleanup_exception();
 
     std::cout << "rtorrent: caught torrent::internal_error: "
               << e.what() << std::endl
@@ -505,7 +506,8 @@ main(int argc, char** argv) {
     return -1;
 
   } catch (std::exception& e) {
-    control->cleanup_exception();
+    if (control != nullptr)
+      control->cleanup_exception();
 
     std::cout << "rtorrent: caught" << typeid(e).name() << " : " << e.what() << std::endl;
 

src/rpc/lua.cc

@@ -394,6 +394,10 @@ execute_lua(LuaEngine* engine, rpc::target_type target_type, torrent::Object con
   switch (raw_args.type()) {
   case torrent::Object::TYPE_LIST: {
     const torrent::Object::list_type& args = raw_args.as_list();
+
+    if (args.empty())
+      throw torrent::input_error("Too few arguments.");
+
     if (flags & LuaEngine::flag_string) {
       check_lua_status(l_state, luaL_loadstring(l_state, args.begin()->as_string().c_str()));
     } else {

test/Makefile.am

@@ -69,6 +69,8 @@ rtorrent_Test_Src_SOURCES = $(rtorrent_Test_Common) \
 	src/test_command_string.h \
 	src/test_command_throttle.cc \
 	src/test_command_throttle.h \
+	src/test_input_path_input.cc \
+	src/test_input_path_input.h \
 	src/test_session_commit.cc \
 	src/test_session_commit.h \
 	src/test_session_storer.cc \

test/src/test_input_path_input.cc

@@ -0,0 +1,77 @@
+#include "config.h"
+
+#include "test/src/test_input_path_input.h"
+
+#include <cstdlib>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "input/path_input.h"
+
+CPPUNIT_TEST_SUITE_REGISTRATION(TestInputPathInput);
+
+void
+TestInputPathInput::setUp() {
+  test_fixture::setUp();
+
+  char temp_dir[] = "/tmp/rtorrent_test_path_input_XXXXXX";
+
+  CPPUNIT_ASSERT(mkdtemp(temp_dir) != nullptr);
+
+  m_temp_dir = temp_dir;
+
+  CPPUNIT_ASSERT_EQUAL(0, mkdir((m_temp_dir + "/alpha").c_str(), 0755));
+  CPPUNIT_ASSERT_EQUAL(0, mkdir((m_temp_dir + "/alpha/beta").c_str(), 0755));
+}
+
+void
+TestInputPathInput::tearDown() {
+  rmdir((m_temp_dir + "/alpha/beta").c_str());
+  rmdir((m_temp_dir + "/alpha").c_str());
+  rmdir(m_temp_dir.c_str());
+
+  test_fixture::tearDown();
+}
+
+// Tab at the end of the line completes the trailing component.
+void
+TestInputPathInput::test_complete_at_end() {
+  input::PathInput input;
+
+  input.str() = m_temp_dir + "/al";
+  input.set_pos(input.str().size());
+
+  CPPUNIT_ASSERT(input.pressed('\t'));
+
+  CPPUNIT_ASSERT_EQUAL(m_temp_dir + "/alpha/", input.str());
+  CPPUNIT_ASSERT_EQUAL(input.str().size(), input.get_pos());
+}
+
+// The same completion with the cursor left inside the line. Only the text up to
+// the cursor selects the entry, and the rest of the line is discarded.
+void
+TestInputPathInput::test_complete_mid_line() {
+  input::PathInput input;
+
+  input.str() = m_temp_dir + "/alZZZ";
+  input.set_pos(m_temp_dir.size() + 3);
+
+  CPPUNIT_ASSERT(input.pressed('\t'));
+
+  CPPUNIT_ASSERT_EQUAL(m_temp_dir + "/alpha/", input.str());
+  CPPUNIT_ASSERT_EQUAL(input.str().size(), input.get_pos());
+}
+
+// A cursor resting on a separator keeps completing the component after it.
+void
+TestInputPathInput::test_cursor_on_separator() {
+  input::PathInput input;
+
+  input.str() = m_temp_dir + "/alpha/be";
+  input.set_pos(m_temp_dir.size() + 6);
+
+  CPPUNIT_ASSERT(input.pressed('\t'));
+
+  CPPUNIT_ASSERT_EQUAL(m_temp_dir + "/alpha/beta/", input.str());
+  CPPUNIT_ASSERT_EQUAL(input.str().size(), input.get_pos());
+}

test/src/test_input_path_input.h

@@ -0,0 +1,24 @@
+#include "test/helpers/test_fixture.h"
+
+#include <string>
+
+class TestInputPathInput : public test_fixture {
+  CPPUNIT_TEST_SUITE(TestInputPathInput);
+
+  CPPUNIT_TEST(test_complete_at_end);
+  CPPUNIT_TEST(test_complete_mid_line);
+  CPPUNIT_TEST(test_cursor_on_separator);
+
+  CPPUNIT_TEST_SUITE_END();
+
+public:
+  void setUp();
+  void tearDown();
+
+  void test_complete_at_end();
+  void test_complete_mid_line();
+  void test_cursor_on_separator();
+
+private:
+  std::string m_temp_dir;
+};