Add initial Skylark byte code generation code.

Does not yet contain any implementation for expressions and statements
but sets up various needed mechanisms and helper classes.

--
MOS_MIGRATED_REVID=107222845

1 files changed, 14 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java b/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java
index 8d1ed36f5d..9c11547a15 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/FunctionDefStatement.java
@@ -13,7 +13,13 @@
 // limitations under the License.
 package com.google.devtools.build.lib.syntax;
 
+import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.syntax.compiler.DebugInfo;
+import com.google.devtools.build.lib.syntax.compiler.LoopLabels;
+import com.google.devtools.build.lib.syntax.compiler.VariableScope;
+
+import net.bytebuddy.implementation.bytecode.ByteCodeAppender;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -117,4 +123,12 @@ public class FunctionDefStatement extends Statement {
       stmts.validate(localEnv);
     }
   }
+
+  @Override
+  ByteCodeAppender compile(
+      VariableScope scope, Optional<LoopLabels> loopLabels, DebugInfo debugInfo) {
+    throw new UnsupportedOperationException(
+        "Skylark does not support nested function definitions"
+            + " and the current entry point for the compiler is UserDefinedFunction.");
+  }
 }