Support cast tree in annotation parameters (#750)

scip-semanticdb/src/main/java/com/sourcegraph/scip_semanticdb/SignatureFormatter.java

@@ -470,6 +470,12 @@ private String formatTree(Tree tree) {
           + formatTree(tree.getAssignTree().getRhs());
     } else if (tree.hasUnaryopTree()) {
       return formatUnaryOperation(tree.getUnaryopTree());
+    } else if (tree.hasCastTree()) {
+      return "("
+          + formatType(tree.getCastTree().getTpe())
+          + ")"
+          + " "
+          + formatTree(tree.getCastTree().getValue());
     }
 
     throw new IllegalArgumentException("tree was of unexpected type " + tree);

semanticdb-java/src/main/java/com/sourcegraph/semanticdb_javac/SemanticdbBuilders.java

@@ -150,6 +150,10 @@ public static Semanticdb.Tree tree(Semanticdb.UnaryOperatorTree unaryOperatorTre
     return Semanticdb.Tree.newBuilder().setUnaryopTree(unaryOperatorTree).build();
   }
 
+  public static Semanticdb.Tree tree(Semanticdb.CastTree castTree) {
+    return Semanticdb.Tree.newBuilder().setCastTree(castTree).build();
+  }
+
   public static Semanticdb.UnaryOperatorTree unaryOpTree(
       Semanticdb.UnaryOperator operator, Semanticdb.Tree rhs) {
     return Semanticdb.UnaryOperatorTree.newBuilder().setOp(operator).setTree(rhs).build();
@@ -163,10 +167,15 @@ public static Semanticdb.AssignTree assignTree(Semanticdb.Tree lhs, Semanticdb.T
     return Semanticdb.AssignTree.newBuilder().setLhs(lhs).setRhs(rhs).build();
   }
 
+  public static Semanticdb.CastTree castTree(Semanticdb.Type type, Semanticdb.Tree value) {
+    return Semanticdb.CastTree.newBuilder().setTpe(type).setValue(value).build();
+  }
+
   public static Semanticdb.AnnotationTree annotationTree(
       Semanticdb.Type type, Iterable<Semanticdb.Tree> parameters) {
     return Semanticdb.AnnotationTree.newBuilder().setTpe(type).addAllParameters(parameters).build();
   }
+
   // SemanticDB Constants
 
   public static Semanticdb.Constant stringConst(String value) {
@@ -181,6 +190,12 @@ public static Semanticdb.Constant doubleConst(Double value) {
         .build();
   }
 
+  public static Semanticdb.Constant nullConst() {
+    return Semanticdb.Constant.newBuilder()
+        .setNullConstant(Semanticdb.NullConstant.newBuilder())
+        .build();
+  }
+
   public static Semanticdb.Constant floatConst(Float value) {
     return Semanticdb.Constant.newBuilder()
         .setFloatConstant(Semanticdb.FloatConstant.newBuilder().setValue(value))

semanticdb-java/src/main/protobuf/semanticdb.proto

@@ -298,6 +298,7 @@ message Tree {
     AssignTree assign_tree = 10;
     BinaryOperatorTree binop_tree = 11;
     UnaryOperatorTree unaryop_tree = 12;
+    CastTree cast_tree = 13;
     // -- OUT OF SPEC -- //
   }
 }
@@ -347,6 +348,12 @@ message AnnotationTree {
   repeated Tree parameters = 2;
 }
 
+
+message CastTree {
+  Type tpe = 1;
+  Tree value = 2;
+}
+
 message AssignTree {
     Tree lhs = 1;
     Tree rhs = 2;

semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/SemanticdbTrees.java

@@ -1,26 +1,13 @@
 package com.sourcegraph.semanticdb_javac;
 
-import com.sun.source.tree.Tree;
+import com.sun.source.tree.*;
 import com.sun.source.util.Trees;
 import javax.lang.model.element.Element;
 import javax.lang.model.util.Types;
+import javax.lang.model.type.TypeMirror;
 import com.sun.source.util.TreePath;
 import com.sun.source.tree.Tree;
 import com.sun.source.tree.Tree.Kind;
-import com.sun.source.tree.BinaryTree;
-import com.sun.source.tree.UnaryTree;
-import com.sun.source.tree.AssignmentTree;
-import com.sun.source.tree.MemberSelectTree;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.tree.VariableTree;
-import com.sun.source.tree.MethodTree;
-import com.sun.source.tree.ModifiersTree;
-import com.sun.source.tree.IdentifierTree;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.LiteralTree;
-import com.sun.source.tree.NewArrayTree;
-import com.sun.source.tree.AnnotationTree;
-import com.sun.source.tree.ParenthesizedTree;
 
 import java.util.HashMap;
 import java.util.ArrayList;
@@ -44,6 +31,7 @@ public SemanticdbTrees(
     this.types = types;
     this.trees = trees;
     this.nodes = nodes;
+    this.typeVisitor = new SemanticdbTypeVisitor(globals, locals, types);
   }
 
   private final GlobalSymbolsCache globals;
@@ -52,6 +40,7 @@ public SemanticdbTrees(
   private final Types types;
   private final Trees trees;
   private final HashMap<Tree, TreePath> nodes;
+  private final SemanticdbTypeVisitor typeVisitor;
 
   public List<Semanticdb.AnnotationTree> annotations(Tree node) {
     if (!(node instanceof ClassTree)
@@ -100,11 +89,15 @@ public Semanticdb.AnnotationTree annotationBuilder(AnnotationTree annotation) {
     TreePath annotationTreePath = nodes.get(annotation);
     Element annotationSym = trees.getElement(annotationTreePath);
 
-    Semanticdb.Type type =
-        new SemanticdbTypeVisitor(globals, locals, types).semanticdbType(annotationSym.asType());
+    Semanticdb.Type type = typeVisitor.semanticdbType(annotationSym.asType());
     return annotationTree(type, params);
   }
 
+  private TypeMirror getTreeType(Tree tree) {
+    TreePath path = nodes.get(tree);
+    return trees.getTypeMirror(path);
+  }
+
   private Semanticdb.Tree annotationParameter(ExpressionTree expr) {
     if (expr instanceof MemberSelectTree) {
       TreePath expressionTreePath = nodes.get(expr);
@@ -125,7 +118,12 @@ private Semanticdb.Tree annotationParameter(ExpressionTree expr) {
       // Literals can either be a primitive or String
       Object value = ((LiteralTree) expr).getValue();
       final Semanticdb.Constant constant;
-      if (value instanceof String) constant = stringConst((String) value);
+      // Technically, annotation parameter values cannot be null,
+      // according to JLS: https://docs.oracle.com/javase/specs/jls/se8/html/jls-9.html#jls-9.7.1
+      // But this codepath is still possible to hit when compiling invalid code - and
+      // we should handle the null const case in order to fail more gracefully
+      if (value == null) constant = nullConst();
+      else if (value instanceof String) constant = stringConst((String) value);
       else if (value instanceof Boolean) constant = booleanConst((Boolean) value);
       else if (value instanceof Byte) constant = byteConst((Byte) value);
       else if (value instanceof Short) constant = shortConst((Short) value);
@@ -164,13 +162,20 @@ private Semanticdb.Tree annotationParameter(ExpressionTree expr) {
     } else if (expr instanceof ParenthesizedTree) {
       ParenthesizedTree parenExpr = (ParenthesizedTree) expr;
       return annotationParameter(parenExpr.getExpression());
+    } else if (expr instanceof TypeCastTree) {
+      TypeCastTree tree = (TypeCastTree) expr;
+      return tree(
+          castTree(
+              typeVisitor.semanticdbType(getTreeType(tree.getType())),
+              annotationParameter(tree.getExpression())));
+    } else {
+      throw new IllegalArgumentException(
+          semanticdbUri
+              + ": annotation parameter rhs was of unexpected tree node type "
+              + expr.getClass()
+              + "\n"
+              + expr);
     }
-    throw new IllegalArgumentException(
-        semanticdbUri
-            + ": annotation parameter rhs was of unexpected tree node type "
-            + expr.getClass()
-            + "\n"
-            + expr);
   }
 
   private Semanticdb.BinaryOperator semanticdbBinaryOperator(Tree.Kind kind) {

semanticdb-javac/src/main/java/com/sourcegraph/semanticdb_javac/SemanticdbVisitor.java

@@ -15,6 +15,7 @@
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.NewClassTree;
 import com.sun.source.tree.MemberSelectTree;
+import com.sun.source.tree.TypeCastTree;
 import com.sun.source.tree.TypeParameterTree;
 import com.sun.source.tree.ParameterizedTypeTree;
 

tests/minimized/src/main/java/minimized/AnnotationParameters.java

@@ -12,6 +12,11 @@
 	String value() default "";
 }
 
+
+@interface BarRef{
+	SuppressWarnings value();
+}
+
 interface Foo {
 	@Bar(-1d)
 	double test();
@@ -25,4 +30,12 @@ interface Foo {
 
 	@Nullable(("what"))
 	Foo test4();
+
+	@Bar((double) -1)
+	double testCast();
+}
+
+interface TestRef {
+	@BarRef(@SuppressWarnings(value = "unchecked"))
+	abstract double testCase();
 }

tests/snapshots/src/main/generated/tests/minimized/src/main/java/minimized/AnnotationParameters.java

@@ -40,6 +40,21 @@
 //            kind AbstractMethod
 }
 
+
+@interface BarRef{
+//         ^^^^^^ definition semanticdb maven . . minimized/BarRef#
+//                display_name BarRef
+//                signature_documentation java @interface BarRef
+//                kind Interface
+//                relationship is_implementation semanticdb maven jdk 11 java/lang/annotation/Annotation#
+→SuppressWarnings value();
+//^^^^^^^^^^^^^^^ reference semanticdb maven jdk 11 java/lang/SuppressWarnings#
+//                ^^^^^ definition semanticdb maven . . minimized/BarRef#value().
+//                      display_name value
+//                      signature_documentation java public abstract SuppressWarnings value()
+//                      kind AbstractMethod
+}
+
 interface Foo {
 //        ^^^ definition semanticdb maven . . minimized/Foo#
 //            display_name Foo
@@ -80,4 +95,28 @@ interface Foo {
 //         display_name test4
 //         signature_documentation java @Nullable("what")\npublic abstract Foo test4()
 //         kind AbstractMethod
+
+→@Bar((double) -1)
+//^^^ reference semanticdb maven . . minimized/Bar#
+→double testCast();
+//      ^^^^^^^^ definition semanticdb maven . . minimized/Foo#testCast().
+//               display_name testCast
+//               signature_documentation java @Bar((double) -1)\npublic abstract double testCast()
+//               kind AbstractMethod
+}
+
+interface TestRef {
+//        ^^^^^^^ definition semanticdb maven . . minimized/TestRef#
+//                display_name TestRef
+//                signature_documentation java interface TestRef
+//                kind Interface
+→@BarRef(@SuppressWarnings(value = "unchecked"))
+//^^^^^^ reference semanticdb maven . . minimized/BarRef#
+//        ^^^^^^^^^^^^^^^^ reference semanticdb maven jdk 11 java/lang/SuppressWarnings#
+//                         ^^^^^ reference semanticdb maven jdk 11 java/lang/SuppressWarnings#value().
+→abstract double testCase();
+//               ^^^^^^^^ definition semanticdb maven . . minimized/TestRef#testCase().
+//                        display_name testCase
+//                        signature_documentation java @BarRef(@SuppressWarnings("unchecked"))\npublic abstract double testCase()
+//                        kind AbstractMethod
 }