AP_Scripting: replace int return from SerialAccess:write() with bool

Avoids the pitfall of 0 being truthy in Lua. Now, `if port:write() then` will work as expected.
ArduPilot · Jun 30, 2024 · b9d7dc4 · b9d7dc4
1 parent 353099a
commit b9d7dc4
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Showing 5 changed files with 6 additions and 6 deletions.
diff --git a/libraries/AP_Scripting/AP_Scripting_SerialAccess.cpp b/libraries/AP_Scripting/AP_Scripting_SerialAccess.cpp
@@ -24,9 +24,9 @@ void AP_Scripting_SerialAccess::begin(uint32_t baud)
     }
 }
 
-int32_t AP_Scripting_SerialAccess::write(uint8_t c)
+bool AP_Scripting_SerialAccess::write(uint8_t c)
 {
-    return (int32_t)write(&c, 1); // return value will be 0 or 1
+    return write(&c, 1) > 0;
 }
 
 size_t AP_Scripting_SerialAccess::write(const uint8_t *buffer, size_t size)

diff --git a/libraries/AP_Scripting/AP_Scripting_SerialAccess.h b/libraries/AP_Scripting/AP_Scripting_SerialAccess.h
@@ -14,7 +14,7 @@ class AP_Scripting_SerialAccess {
 
     void begin(uint32_t baud);
 
-    int32_t write(uint8_t c);
+    bool write(uint8_t c);
     size_t write(const uint8_t *buffer, size_t size);
 
     bool read(uint8_t &c);

diff --git a/libraries/AP_Scripting/docs/docs.lua b/libraries/AP_Scripting/docs/docs.lua
@@ -1239,7 +1239,7 @@ function AP_Scripting_SerialAccess_ud:begin(baud_rate) end
 
 -- Writes a single byte
 ---@param value integer -- byte to write
----@return integer -- 1 if success else 0
+---@return boolean -- true if successfully written
 function AP_Scripting_SerialAccess_ud:write(value) end
 
 -- Writes a string. The number of bytes actually written, i.e. the length of the

diff --git a/libraries/AP_Scripting/generator/description/bindings.desc b/libraries/AP_Scripting/generator/description/bindings.desc
@@ -396,7 +396,7 @@ include AP_Scripting/AP_Scripting_SerialAccess.h
 -- don't let user create access objects
 userdata AP_Scripting_SerialAccess creation null -1
 userdata AP_Scripting_SerialAccess method begin void int32_t 1 INT32_MAX
-userdata AP_Scripting_SerialAccess method write int32_t uint8_t'skip_check
+userdata AP_Scripting_SerialAccess method write boolean uint8_t'skip_check
 userdata AP_Scripting_SerialAccess manual writestring lua_serial_writestring 1 1
 userdata AP_Scripting_SerialAccess manual read lua_serial_read 0 1
 userdata AP_Scripting_SerialAccess manual readstring lua_serial_readstring 1 1

diff --git a/libraries/AP_Scripting/tests/serial_loopback.lua b/libraries/AP_Scripting/tests/serial_loopback.lua
@@ -11,7 +11,7 @@ function test_driver_to_device()
   local msg_send = "hello device"
   local num_sent = 0
   for ci = 1,#msg_send do
-    num_sent = num_sent + ser_driver:write(msg_send:byte(ci, ci))
+    num_sent = num_sent + (ser_driver:write(msg_send:byte(ci, ci)) and 1 or 0)
   end
   local msg_recv = ser_device:readstring(#msg_send)
   if msg_send == msg_recv and num_sent == #msg_send then