Remove need for skip-build, don't write empty file

* No longer necessary to specify skip-build because it will be
detected automatically
* Don't count whitespace as meaningful output

Bootstrap.cake

@@ -1,5 +1,3 @@
-(skip-build)
-
 (set-cakelisp-option executable-output "bin/cakelisp")
 
 (add-c-search-directory-module "src")

Bootstrap_MSVC.cake

@@ -1,5 +1,3 @@
-(skip-build)
-
 (set-cakelisp-option executable-output "bin/cakelisp.exe")
 
 (add-c-search-directory-module "src")

CrossCompile_Windows.cake

@@ -1,5 +1,3 @@
-(skip-build)
-
 (set-cakelisp-option executable-output "bin/cakelisp.exe")
 
 (add-c-search-directory-module "src")

runtime/BuildTools.cake

@@ -1,7 +1,6 @@
 ;; Build Tools - useful macros/functions for compile-time code
 ;; These rely on Cakelisp, so don't expect it to work outside comptime
 
-(skip-build)
 (import "ComptimeHelpers.cake")
 
 ;; Returns exit code (0 = success)

runtime/CHelpers.cake

@@ -1,5 +1,3 @@
-(skip-build)
-
 (import "ComptimeHelpers.cake")
 
 ;; Unlike scope, this does not create a scope, which is useful when you don't want a scope but do

runtime/ComptimeHelpers.cake

@@ -1,5 +1,3 @@
-(skip-build)
-
 (import &comptime-only "CppHelpers.cake")
 
 ;; Binds the variable's address to the named var

runtime/Config_Linux.cake

@@ -1,2 +1 @@
-(skip-build)
 (comptime-define-symbol 'Unix)

runtime/Config_Mingw.cake

@@ -1,4 +1,3 @@
-(skip-build)
 (comptime-define-symbol 'Windows)
 
 ;; TODO: Remove. These are only to ease testing via cross-compilation

runtime/Config_Windows.cake

@@ -1,2 +1 @@
-(skip-build)
-(comptime-define-symbol 'Windows)
+(comptime-define-symbol 'Windows)

runtime/CppHelpers.cake

@@ -1,4 +1,3 @@
-(skip-build)
 (import "CHelpers.cake")
 
 (defmacro std-str-equals (std-string-var any str any)

src/Evaluator.cpp

@@ -2120,12 +2120,20 @@ bool StringOutputHasAnyMeaningfulOutput(const std::vector<StringOutput>* stringO
 	{
 		if (output.modifiers == StringOutMod_Splice)
 		{
-			bool spliceHadMeaningfulOutput =
-			    (isHeader ?
-			         StringOutputHasAnyMeaningfulOutput(&output.spliceOutput->header, isHeader) :
-			         StringOutputHasAnyMeaningfulOutput(&output.spliceOutput->source, isHeader));
-			if (spliceHadMeaningfulOutput)
-				return true;
+			if (output.spliceOutput)
+			{
+				const std::vector<StringOutput>* outputToCheck =
+				    isHeader ? &output.spliceOutput->header : &output.spliceOutput->source;
+				bool spliceHadMeaningfulOutput =
+				    StringOutputHasAnyMeaningfulOutput(outputToCheck, isHeader);
+				if (spliceHadMeaningfulOutput)
+					return true;
+			}
+		}
+		else if (output.modifiers & (StringOutMod_NewlineAfter | StringOutMod_SpaceAfter |
+		                             StringOutMod_SpaceBefore | StringOutMod_None))
+		{
+			// Not actually meaningful output
 		}
 		else  // Anything else should actually output
 			return true;

src/ModuleManager.cpp

@@ -577,6 +577,15 @@ bool moduleManagerWriteGeneratedOutput(ModuleManager& manager)
 		WriterOutputSettings outputSettings;
 		outputSettings.sourceCakelispFilename = module->filename;
 
+		if (!StringOutputHasAnyMeaningfulOutput(&module->generatedOutput->source, false))
+		{
+			if (logging.buildProcess)
+				Logf("note: not writing module %s because it has no meaningful output\n",
+				     module->filename);
+			module->skipBuild = true;
+			continue;
+		}
+
 		GeneratorOutput header;
 		GeneratorOutput footer;
 		// Something to attach the reason for generating this output
@@ -906,17 +915,20 @@ static bool moduleManagerGetObjectsToBuild(ModuleManager& manager,
 
 		// We do this late so that the file can still affect the build arguments without getting
 		// built itself
-		if (!StringOutputHasAnyMeaningfulOutput(&module->generatedOutput->source, false))
 		{
-			if (logging.buildProcess)
-				Logf("note: not building module %s because it has no meaningful output\n",
-				     module->sourceOutputName.c_str());
-			continue;
-		}
-		// Explicitly marked to not build
-		if (module->skipBuild)
-		{
-			continue;
+			// Explicitly marked to not build or automatically excluded
+			if (module->skipBuild)
+			{
+				continue;
+			}
+
+			if (!StringOutputHasAnyMeaningfulOutput(&module->generatedOutput->source, false))
+			{
+				if (logging.buildProcess)
+					Logf("note: not building module %s because it has no meaningful output\n",
+					     module->sourceOutputName.c_str());
+				continue;
+			}
 		}
 
 		char buildObjectName[MAX_PATH_LENGTH] = {0};

test/Export.cake

@@ -1,4 +1,3 @@
-(skip-build)
 (export
  (add-cakelisp-search-directory "runtime")
  (import "CHelpers.cake"))

test/RunTests.cake

@@ -1,5 +1,3 @@
-;; (skip-build)
-
 (add-cakelisp-search-directory "runtime")
 (import "BuildTools.cake" "ComptimeHelpers.cake" "CHelpers.cake" "Cakelisp.cake")