From 7875e483c0ca07f5a0f3fd6b03a82fb599727cac Mon Sep 17 00:00:00 2001
From: Matt VanNuys <matt.vannuys@willowtreeapps.com>
Date: Fri, 2 Feb 2018 12:37:24 -0500
Subject: [PATCH 1/3] Initial swipe at adding conditional compilation support
 to the BrightScript grammar

---
 grammar/BrightScript.g4 | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/grammar/BrightScript.g4 b/grammar/BrightScript.g4
index afe2615..9226dd5 100644
--- a/grammar/BrightScript.g4
+++ b/grammar/BrightScript.g4
@@ -23,6 +23,7 @@ block
 
 blockStatement
     : comment
+    | conditionalCompilationStatement
     | dimStatement
     | exitStatement
     | forStatement
@@ -50,6 +51,15 @@ associativeElementInitializer
     : (identifier | reservedWord | stringLiteral) COLON assignableExpression
     ;
 
+conditionalCompilationStatement
+    : CONDITIONAL_COMPILATION CONST untypedIdentifier EQUALS expression
+    | CONDITIONAL_COMPILATION ERROR .*?
+    | CONDITIONAL_COMPILATION IF expression
+    | CONDITIONAL_COMPILATION (ELSEIF | ELSE IF) expression
+    | CONDITIONAL_COMPILATION ELSE expression
+    | CONDITIONAL_COMPILATION (ENDIF | END IF)
+    ;
+
 dimStatement
     : DIM identifier OPEN_BRACKET parameterList CLOSE_BRACKET
     ;
@@ -313,6 +323,10 @@ BOX
     : B O X
 	;
 
+CONST
+    : C O N S T
+    ;
+
 CREATEOBJECT
     : C R E A T E O B J E C T
     ;
@@ -361,6 +375,10 @@ ENDWHILE
     : E N D W H I L E
 	;
 
+ERROR
+    : E R R O R
+    ;
+
 EXIT
     : E X I T
 	;
@@ -547,7 +565,7 @@ IDENTIFIER_TYPE_DECLARATION
     ;
 
 COMMENT
-    :   (SINGLE_QUOTE | (REM (WS | NEWLINE))) ~[\r\n\u2028\u2029]* -> channel(HIDDEN)
+    : (SINGLE_QUOTE | (REM (WS | NEWLINE))) ~[\r\n\u2028\u2029]* -> channel(HIDDEN)
     ;
 
 NEWLINE
@@ -558,6 +576,10 @@ WS
     : [ \t]+ -> skip
     ;
 
+CONDITIONAL_COMPILATION
+    : '#'
+    ;
+
 SINGLE_QUOTE
     : '\''
     ;

From cf7ba3595ad2adb1420bde15a31427f72c82ece6 Mon Sep 17 00:00:00 2001
From: Matt VanNuys <matt.vannuys@willowtreeapps.com>
Date: Fri, 2 Feb 2018 13:15:22 -0500
Subject: [PATCH 2/3] Conditional compilation seems to work; needs more testing

---
 grammar/BrightScript.g4 | 48 ++++++++++++++++++++++++++---------------
 1 file changed, 31 insertions(+), 17 deletions(-)

diff --git a/grammar/BrightScript.g4 b/grammar/BrightScript.g4
index 9226dd5..2627861 100644
--- a/grammar/BrightScript.g4
+++ b/grammar/BrightScript.g4
@@ -5,7 +5,7 @@ startRule
     ;
 
 component
-    : endOfLine* libraryStatement* endOfLine* componentBody
+    : endOfLine* (libraryStatement* | (conditionalCompilationStatement endOfLine)*) endOfLine* componentBody
     ;
 
 componentBody
@@ -52,12 +52,12 @@ associativeElementInitializer
     ;
 
 conditionalCompilationStatement
-    : CONDITIONAL_COMPILATION CONST untypedIdentifier EQUALS expression
-    | CONDITIONAL_COMPILATION ERROR .*?
-    | CONDITIONAL_COMPILATION IF expression
-    | CONDITIONAL_COMPILATION (ELSEIF | ELSE IF) expression
-    | CONDITIONAL_COMPILATION ELSE expression
-    | CONDITIONAL_COMPILATION (ENDIF | END IF)
+    : CONDITIONAL_CONST untypedIdentifier EQUALS expression
+    | CONDITIONAL_ERROR .*?
+    | CONDITIONAL_IF expression
+    | CONDITIONAL_ELSEIF expression
+    | CONDITIONAL_ELSE expression
+    | CONDITIONAL_ENDIF
     ;
 
 dimStatement
@@ -323,10 +323,6 @@ BOX
     : B O X
 	;
 
-CONST
-    : C O N S T
-    ;
-
 CREATEOBJECT
     : C R E A T E O B J E C T
     ;
@@ -375,10 +371,6 @@ ENDWHILE
     : E N D W H I L E
 	;
 
-ERROR
-    : E R R O R
-    ;
-
 EXIT
     : E X I T
 	;
@@ -576,8 +568,30 @@ WS
     : [ \t]+ -> skip
     ;
 
-CONDITIONAL_COMPILATION
-    : '#'
+CONDITIONAL_CONST
+    : '#' C O N S T
+    ;
+
+CONDITIONAL_ELSE
+    : '#' ELSE
+    ;
+
+CONDTIONAL_ELSEIF
+    : '#' ELSEIF
+    | '#' ELSE IF
+    ;
+
+CONDITIONAL_ENDIF
+    : '#' ENDIF
+    | '#' END IF
+    ;
+
+CONDITIONAL_ERROR
+    : '#' E R R O R
+    ;
+
+CONDITIONAL_IF
+    : '#' IF
     ;
 
 SINGLE_QUOTE

From 20043dd8daa8ab2d5042094725721ef576c948f4 Mon Sep 17 00:00:00 2001
From: Matt VanNuys <matt.vannuys@willowtreeapps.com>
Date: Mon, 5 Feb 2018 14:42:59 -0500
Subject: [PATCH 3/3] Fix a typo, definition of else, and add some test
 scenarios to sample-project

---
 grammar/BrightScript.g4              | 24 ++++++++++++++++--------
 sample-project/source/GoodSyntax.brs |  9 +++++++++
 2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/grammar/BrightScript.g4 b/grammar/BrightScript.g4
index 2627861..69bb999 100644
--- a/grammar/BrightScript.g4
+++ b/grammar/BrightScript.g4
@@ -5,11 +5,21 @@ startRule
     ;
 
 component
-    : endOfLine* (libraryStatement* | (conditionalCompilationStatement endOfLine)*) endOfLine* componentBody
+    : componentHead componentBody
+    ;
+
+componentHead
+    : endOfLine* componentHeadElement (endOfLine+ componentHeadElement)* endOfLine*
+    ;
+
+componentHeadElement
+    : libraryStatement
+    | conditionalCompilationStatement
+    | comment
     ;
 
 componentBody
-    : componentBodyElement (endOfLine+ componentBodyElement)* endOfLine*
+    : endOfLine* componentBodyElement (endOfLine+ componentBodyElement)* endOfLine*
     ;
 
 componentBodyElement
@@ -56,7 +66,7 @@ conditionalCompilationStatement
     | CONDITIONAL_ERROR .*?
     | CONDITIONAL_IF expression
     | CONDITIONAL_ELSEIF expression
-    | CONDITIONAL_ELSE expression
+    | CONDITIONAL_ELSE
     | CONDITIONAL_ENDIF
     ;
 
@@ -576,14 +586,12 @@ CONDITIONAL_ELSE
     : '#' ELSE
     ;
 
-CONDTIONAL_ELSEIF
-    : '#' ELSEIF
-    | '#' ELSE IF
+CONDITIONAL_ELSEIF
+    : '#' (ELSE WS IF | ELSEIF)
     ;
 
 CONDITIONAL_ENDIF
-    : '#' ENDIF
-    | '#' END IF
+    : '#' (END WS IF | ENDIF)
     ;
 
 CONDITIONAL_ERROR
diff --git a/sample-project/source/GoodSyntax.brs b/sample-project/source/GoodSyntax.brs
index d73d3d5..2be28c9 100644
--- a/sample-project/source/GoodSyntax.brs
+++ b/sample-project/source/GoodSyntax.brs
@@ -1,11 +1,20 @@
 ' This is a sample file containing syntax that compiles properly
 
+#const debug = true
+
 REM Although the file compiles,
 REM
 REM Not all linting rules pass
 
 sub DefaultMain()
+    #if debug = true
+    print "debug mode enabled"
+    #else
+    print "debug mode disabled"
+    #end if
+    
     print "in showChannelSGScreen"
+
     'Indicate this is a Roku SceneGraph application'
     screen = CreateObject("roSGScreen")
     m.port = CreateObject("roMessagePort")