Use a real syntax file

README.md

@@ -48,3 +48,10 @@ function! b:MyStatusLine()
 endfunction
 setl statusline=%!b:MyStatusLine()
 ```
+
+## License
+Everything is under the [MIT
+License](https://github.com/stevearc/vim-arduino/blob/master/LICENSE) except for
+the wonderful syntax file, which was created by Johannes Hoff and copied from
+[vim.org](http://www.vim.org/scripts/script.php?script_id=2654) and is under the
+[Vim License](http://vimdoc.sourceforge.net/htmldoc/uganda.html).

syntax/arduino.vim

@@ -1,6 +1,67 @@
-" The simplest possible arduino syntax file. Just uses C++.
-if exists("b:current_syntax")
+" Vim syntax file
+" Language:    Arduino
+" Maintainer:  Johannes Hoff <johannes@johanneshoff.com>
+" Last Change: 17 May 2015
+" License:     VIM license (:help license, replace vim by arduino.vim)
+
+" Syntax highlighting like in the Arduino IDE
+" Automatically generated by the script available at
+"    https://bitbucket.org/johannes/arduino-vim-syntax
+" Using keywords from <arduino>/build/shared/lib/keywords.txt
+" From version: ARDUINO 1.6.4 - 2015.05.06
+
+" Thanks to Rik, Erik Nomitch, Adam Obeng, Graeme Cross and Niall Parker
+" for helpful feedback!
+
+" For version 5.x: Clear all syntax items
+" For version 6.x: Quit when a syntax file was already loaded
+if version < 600
+  syntax clear
+elseif exists("b:current_syntax")
   finish
 endif
 
-runtime! syntax/cpp.vim
+" Read the C syntax to start with
+if version < 600
+  so <sfile>:p:h/cpp.vim
+else
+  runtime! syntax/cpp.vim
+endif
+
+syn keyword arduinoConstant  BIN CHANGE DEC DEFAULT EXTERNAL FALLING HALF_PI HEX
+syn keyword arduinoConstant  HIGH INPUT INPUT_PULLUP INTERNAL INTERNAL1V1
+syn keyword arduinoConstant  INTERNAL2V56 LOW LSBFIRST MSBFIRST OCT OUTPUT PI
+syn keyword arduinoConstant  RISING TWO_PI
+
+syn keyword arduinoFunc      analogRead analogReference analogWrite
+syn keyword arduinoFunc      attachInterrupt bit bitClear bitRead bitSet
+syn keyword arduinoFunc      bitWrite delay delayMicroseconds detachInterrupt
+syn keyword arduinoFunc      digitalRead digitalWrite highByte interrupts
+syn keyword arduinoFunc      lowByte micros millis noInterrupts noTone pinMode
+syn keyword arduinoFunc      pulseIn shiftIn shiftOut tone yield
+
+syn keyword arduinoMethod    available availableForWrite begin charAt compareTo
+syn keyword arduinoMethod    concat end endsWith equals equalsIgnoreCase find
+syn keyword arduinoMethod    findUntil flush getBytes indexOf lastIndexOf length
+syn keyword arduinoMethod    loop parseFloat parseInt peek print println read
+syn keyword arduinoMethod    readBytes readBytesUntil readString readStringUntil
+syn keyword arduinoMethod    replace setCharAt setTimeout setup startsWith
+syn keyword arduinoMethod    substring toCharArray toInt toLowerCase toUpperCase
+syn keyword arduinoMethod    trim word
+
+syn keyword arduinoModule    Keyboard Mouse Serial Serial1 Serial2 Serial3
+syn keyword arduinoModule    SerialUSB
+
+syn keyword arduinoStdFunc   abs accept acos asin atan atan2 ceil click constrain
+syn keyword arduinoStdFunc   cos degrees exp floor isPressed log map max min
+syn keyword arduinoStdFunc   move pow press radians random randomSeed release
+syn keyword arduinoStdFunc   releaseAll round sin sq sqrt tan
+
+syn keyword arduinoType      boolean byte null String word
+
+hi def link arduinoType Type
+hi def link arduinoConstant Constant
+hi def link arduinoStdFunc Function
+hi def link arduinoFunc Function
+hi def link arduinoMethod Function
+hi def link arduinoModule Identifier