Fix issue 1860; exception thrown in the parser on if/if-else/for/while/do-while

statements with no body.

OpenSim/Region/ScriptEngine/DotNetEngine/Compiler/LSL/CSCodeGenerator.cs

@@ -388,14 +388,18 @@ namespace OpenSim.Region.ScriptEngine.DotNetEngine.Compiler.LSL
         private string GenerateStatement(Statement s)
         {
             string retstr = String.Empty;
-
+            bool printSemicolon = true;
-            // Jump label prints its own colon, we don't need a semicolon.
-            bool printSemicolon = !(s.kids.Top is JumpLabel);
 
             retstr += Indent();
 
+            if (0 < s.kids.Count)
+            {
+                // Jump label prints its own colon, we don't need a semicolon.
+                printSemicolon = !(s.kids.Top is JumpLabel);
+
                 foreach (SYMBOL kid in s.kids)
                     retstr += GenerateNode(kid);
+            }
 
             if (printSemicolon)
                 retstr += GenerateLine(";");

OpenSim/Region/ScriptEngine/DotNetEngine/Compiler/LSL/lsl.parser.cs

@@ -359,7 +359,7 @@ public override int yynum { get { return 114; }}
 public StateChange(Parser yyp):base(yyp){}}
 //%+IfStatement+115
 public class IfStatement : SYMBOL{
- private  void  AddStatement ( Statement  s ){ if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ private  void  AddStatement ( Statement  s ){ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
  public  IfStatement (Parser yyp, Expression  e , Statement  ifs ):base(((LSLSyntax
@@ -369,7 +369,7 @@ public class IfStatement : SYMBOL{
  public  IfStatement (Parser yyp, Expression  e , Statement  ifs , Statement  es ):base(((LSLSyntax
 )yyp)){ kids . Add ( e );
  AddStatement ( ifs );
- if ( es . kids . Top  is  IfStatement ) kids . Add ( es . kids . Pop ());
+ if (0< es . kids . Count && es . kids . Top  is  IfStatement ) kids . Add ( es . kids . Pop ());
  else  AddStatement ( es );
 }
 
@@ -380,7 +380,7 @@ public IfStatement(Parser yyp):base(yyp){}}
 public class WhileStatement : SYMBOL{
  public  WhileStatement (Parser yyp, Expression  e , Statement  s ):base(((LSLSyntax
 )yyp)){ kids . Add ( e );
- if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
 
@@ -390,7 +390,7 @@ public WhileStatement(Parser yyp):base(yyp){}}
 //%+DoWhileStatement+117
 public class DoWhileStatement : SYMBOL{
  public  DoWhileStatement (Parser yyp, Expression  e , Statement  s ):base(((LSLSyntax
-)yyp)){ if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+)yyp)){ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
  kids . Add ( e );
 }
@@ -404,7 +404,7 @@ public class ForLoop : SYMBOL{
 )yyp)){ kids . Add ( flsa );
  kids . Add ( e );
  kids . Add ( flsb );
- if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
 

OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGenerator.cs

@@ -388,14 +388,18 @@ namespace OpenSim.Region.ScriptEngine.Shared.CodeTools
         private string GenerateStatement(Statement s)
         {
             string retstr = String.Empty;
-
+            bool printSemicolon = true;
-            // Jump label prints its own colon, we don't need a semicolon.
-            bool printSemicolon = !(s.kids.Top is JumpLabel);
 
             retstr += Indent();
 
+            if (0 < s.kids.Count)
+            {
+                // Jump label prints its own colon, we don't need a semicolon.
+                printSemicolon = !(s.kids.Top is JumpLabel);
+
                 foreach (SYMBOL kid in s.kids)
                     retstr += GenerateNode(kid);
+            }
 
             if (printSemicolon)
                 retstr += GenerateLine(";");

OpenSim/Region/ScriptEngine/Shared/CodeTools/lsl.parser.cs

@@ -359,7 +359,7 @@ public override int yynum { get { return 114; }}
 public StateChange(Parser yyp):base(yyp){}}
 //%+IfStatement+115
 public class IfStatement : SYMBOL{
- private  void  AddStatement ( Statement  s ){ if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ private  void  AddStatement ( Statement  s ){ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
  public  IfStatement (Parser yyp, Expression  e , Statement  ifs ):base(((LSLSyntax
@@ -369,7 +369,7 @@ public class IfStatement : SYMBOL{
  public  IfStatement (Parser yyp, Expression  e , Statement  ifs , Statement  es ):base(((LSLSyntax
 )yyp)){ kids . Add ( e );
  AddStatement ( ifs );
- if ( es . kids . Top  is  IfStatement ) kids . Add ( es . kids . Pop ());
+ if (0< es . kids . Count && es . kids . Top  is  IfStatement ) kids . Add ( es . kids . Pop ());
  else  AddStatement ( es );
 }
 
@@ -380,7 +380,7 @@ public IfStatement(Parser yyp):base(yyp){}}
 public class WhileStatement : SYMBOL{
  public  WhileStatement (Parser yyp, Expression  e , Statement  s ):base(((LSLSyntax
 )yyp)){ kids . Add ( e );
- if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
 
@@ -390,7 +390,7 @@ public WhileStatement(Parser yyp):base(yyp){}}
 //%+DoWhileStatement+117
 public class DoWhileStatement : SYMBOL{
  public  DoWhileStatement (Parser yyp, Expression  e , Statement  s ):base(((LSLSyntax
-)yyp)){ if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+)yyp)){ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
  kids . Add ( e );
 }
@@ -404,7 +404,7 @@ public class ForLoop : SYMBOL{
 )yyp)){ kids . Add ( flsa );
  kids . Add ( e );
  kids . Add ( flsb );
- if ( s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
+ if (0< s . kids . Count && s . kids . Top  is  CompoundStatement ) kids . Add ( s . kids . Pop ());
  else  kids . Add ( s );
 }
 

OpenSim/Tests/OpenSim/Region/ScriptEngine/Shared/CodeTools/CSCodeGeneratorTest.cs

@@ -1394,6 +1394,131 @@ default
             Assert.AreEqual(expected, output);
         }
 
+        [Test]
+        public void TestWhileLoopWithNoBody()
+        {
+            string input = @"default
+{
+    state_entry()
+    {
+        while(1<0);
+    }
+}";
+
+            string expected = @"
+        public void default_event_state_entry()
+        {
+            while (1 < 0)
+                ;
+        }
+";
+
+            CSCodeGenerator cg = new CSCodeGenerator();
+            string output = cg.Convert(input);
+            Assert.AreEqual(expected, output);
+        }
+
+        [Test]
+        public void TestDoWhileLoopWithNoBody()
+        {
+            string input = @"default
+{
+    state_entry()
+    {
+        do;
+        while(1<0);
+    }
+}";
+
+            string expected = @"
+        public void default_event_state_entry()
+        {
+            do
+                ;
+            while (1 < 0);
+        }
+";
+
+            CSCodeGenerator cg = new CSCodeGenerator();
+            string output = cg.Convert(input);
+            Assert.AreEqual(expected, output);
+        }
+
+        [Test]
+        public void TestIfWithNoBody()
+        {
+            string input = @"default
+{
+    state_entry()
+    {
+        if(1<0);
+    }
+}";
+
+            string expected = @"
+        public void default_event_state_entry()
+        {
+            if (1 < 0)
+                ;
+        }
+";
+
+            CSCodeGenerator cg = new CSCodeGenerator();
+            string output = cg.Convert(input);
+            Assert.AreEqual(expected, output);
+        }
+
+        [Test]
+        public void TestIfElseWithNoBody()
+        {
+            string input = @"default
+{
+    state_entry()
+    {
+        if(1<0);
+        else;
+    }
+}";
+
+            string expected = @"
+        public void default_event_state_entry()
+        {
+            if (1 < 0)
+                ;
+            else
+                ;
+        }
+";
+
+            CSCodeGenerator cg = new CSCodeGenerator();
+            string output = cg.Convert(input);
+            Assert.AreEqual(expected, output);
+        }
+
+        [Test]
+        public void TestForLoopWithNoBody()
+        {
+            string input = @"default
+{
+    state_entry()
+    {
+        for(x = 4; 1<0; x += 2);
+    }
+}";
+
+            string expected = @"
+        public void default_event_state_entry()
+        {
+            for (x = 4; 1 < 0; x += 2)
+                ;
+        }
+";
+
+            CSCodeGenerator cg = new CSCodeGenerator();
+            string output = cg.Convert(input);
+            Assert.AreEqual(expected, output);
+        }
+
         [Test]
         [ExpectedException("Tools.CSToolsException")]
         public void TestSyntaxError()