added support for @@foo||=42, a lot of changes for a very stupid func…

…tionality, unfortunately used in crap projects such as minitest

git-svn-id: http://svn.macosforge.org/repository/ruby/MacRuby/branches/experimental@2154 23306eb0-4c56-4727-a40e-e92c0eb68959

compiler.cpp

@@ -1071,6 +1071,25 @@ RoxorCompiler::compile_ivar_assignment(ID vid, Value *val)
     return val;
 }
 
+Value *
+RoxorCompiler::compile_cvar_get(ID id, bool check)
+{
+    if (cvarGetFunc == NULL) {
+	// VALUE rb_vm_cvar_get(VALUE klass, ID id, unsigned char check);
+	cvarGetFunc = cast<Function>(module->getOrInsertFunction(
+		    "rb_vm_cvar_get", 
+		    RubyObjTy, RubyObjTy, IntTy, Type::Int8Ty, NULL));
+    }
+
+    std::vector<Value *> params;
+
+    params.push_back(compile_current_class());
+    params.push_back(compile_id(id));
+    params.push_back(ConstantInt::get(Type::Int8Ty, check ? 1 : 0));
+
+    return compile_protected_call(cvarGetFunc, params);
+}
+
 Value *
 RoxorCompiler::compile_cvar_assignment(ID name, Value *val)
 {
@@ -3054,24 +3073,8 @@ RoxorCompiler::compile_node(NODE *node)
 	    break;
 
 	case NODE_CVAR:
-	    {
-		assert(node->nd_vid > 0);
-
-		if (cvarGetFunc == NULL) {
-		    // VALUE rb_vm_cvar_get(VALUE klass, ID id);
-		    cvarGetFunc = cast<Function>(module->getOrInsertFunction(
-				"rb_vm_cvar_get", 
-				RubyObjTy, RubyObjTy, IntTy, NULL));
-		}
-
-		std::vector<Value *> params;
-
-		params.push_back(compile_current_class());
-		params.push_back(compile_id(node->nd_vid));
-
-		return compile_protected_call(cvarGetFunc, params);
-	    }
-	    break;
+	    assert(node->nd_vid > 0);
+	    return compile_cvar_get(node->nd_vid, true);
 
 	case NODE_CVASGN:
 	    assert(node->nd_vid > 0);
@@ -3108,8 +3111,20 @@ RoxorCompiler::compile_node(NODE *node)
 	    {
 		assert(node->nd_recv != NULL);
 		assert(node->nd_value != NULL);
-
-		Value *recvVal = compile_node(node->nd_recv);
+
+		Value *recvVal;
+		if (nd_type(node->nd_recv) == NODE_CVAR) {
+		    // @@foo ||= 42
+		    // We need to compile the class variable retrieve to not
+		    // raise an exception in case the variable has never been
+		    // defined yet.
+		    assert(node->nd_recv->nd_vid > 0);
+		    recvVal = compile_cvar_get(node->nd_recv->nd_vid, false);
+		}
+		else {
+		    recvVal = compile_node(node->nd_recv);
+		}
+
 
 		Value *falseCond = new ICmpInst(ICmpInst::ICMP_EQ, recvVal, falseVal, "", bb);
 

compiler.h

@@ -224,6 +224,7 @@ class RoxorCompiler {
 	Value *compile_ivar_read(ID vid);
 	Value *compile_ivar_assignment(ID vid, Value *val);
 	Value *compile_cvar_assignment(ID vid, Value *val);
+	Value *compile_cvar_get(ID vid, bool check);
 	Value *compile_gvar_assignment(NODE *node, Value *val);
 	Value *compile_constant_declaration(NODE *node, Value *val);
 	Value *compile_multiple_assignment(NODE *node, Value *val);

include/ruby/intern.h

@@ -652,6 +652,7 @@ void rb_const_set(VALUE, ID, VALUE);
 VALUE rb_cvar_defined(VALUE, ID);
 void rb_cvar_set(VALUE, ID, VALUE);
 VALUE rb_cvar_get(VALUE, ID);
+VALUE rb_cvar_get2(VALUE klass, ID id, bool check);
 void rb_cv_set(VALUE, const char*, VALUE);
 VALUE rb_cv_get(VALUE, const char*);
 void rb_define_class_variable(VALUE, const char*, VALUE);

variable.c

@@ -1945,7 +1945,7 @@ rb_cvar_set(VALUE klass, ID id, VALUE val)
 }
 
 VALUE
-rb_cvar_get(VALUE klass, ID id)
+rb_cvar_get2(VALUE klass, ID id, bool check)
 {
     VALUE value, tmp, front = 0, target = 0;
     CFMutableDictionaryRef iv_dict;
@@ -1956,8 +1956,13 @@ rb_cvar_get(VALUE klass, ID id)
     }
     CVAR_LOOKUP(&value, {if (!front) front = klass; target = klass;});
     if (!target) {
-	rb_name_error(id,"uninitialized class variable %s in %s",
-		      rb_id2name(id), rb_class2name(tmp));
+	if (check) {
+	    rb_name_error(id,"uninitialized class variable %s in %s",
+		    rb_id2name(id), rb_class2name(tmp));
+	}
+	else {
+	    return Qnil;
+	}
     }
     if (front && target != front) {
 	ID did = id;
@@ -1974,6 +1979,12 @@ rb_cvar_get(VALUE klass, ID id)
     return value;
 }
 
+VALUE
+rb_cvar_get(VALUE klass, ID id)
+{
+    return rb_cvar_get2(klass, id, true);
+}
+
 VALUE
 rb_cvar_defined(VALUE klass, ID id)
 {

vm.cpp

@@ -1006,13 +1006,13 @@ rb_vm_ivar_set(VALUE obj, ID name, VALUE val, int *slot_cache)
 
 extern "C"
 VALUE
-rb_vm_cvar_get(VALUE klass, ID id)
+rb_vm_cvar_get(VALUE klass, ID id, unsigned char check)
 {
     Class k = GET_VM()->get_current_class();
     if (k != NULL) {
 	klass = (VALUE)k;
     }
-    return rb_cvar_get(klass, id);
+    return rb_cvar_get2(klass, id, check);
 }
 
 extern "C"