feat(api): add DecorationsRequest filter for build config (#3449)

kythe/go/serving/xrefs/xrefs.go

@@ -262,6 +262,7 @@ func (t *Table) Decorations(ctx context.Context, req *xpb.DecorationsRequest) (*
 
 	if req.References {
 		patterns := xrefs.ConvertFilters(req.Filter)
+		buildConfigs := stringset.New(req.BuildConfig...)
 
 		reply.Reference = make([]*xpb.DecorationsReply_Reference, 0, len(decor.Decoration))
 		reply.Nodes = make(map[string]*cpb.NodeInfo, len(decor.Target))
@@ -292,6 +293,11 @@ func (t *Table) Decorations(ctx context.Context, req *xpb.DecorationsRequest) (*
 		bindings := stringset.New()
 
 		for _, d := range decor.Decoration {
+			// Filter decorations by requested build configs.
+			if len(buildConfigs) != 0 && !buildConfigs.Contains(d.Anchor.BuildConfiguration) {
+				continue
+			}
+
 			start, end, exists := patcher.Patch(d.Anchor.StartOffset, d.Anchor.EndOffset)
 			// Filter non-existent anchor.  Anchors can no longer exist if we were
 			// given a dirty buffer and the anchor was inside a changed region.
@@ -394,6 +400,7 @@ func decorationToReference(norm *span.Normalizer, d *srvpb.FileDecorations_Decor
 		Kind:             d.Kind,
 		Span:             span,
 		TargetDefinition: d.TargetDefinition,
+		BuildConfig:      d.Anchor.BuildConfiguration,
 	}
 }
 

kythe/go/serving/xrefs/xrefs_test.go

@@ -187,6 +187,8 @@ var (
 							Ticket:      "kythe://c?lang=otpl?path=/a/path#6-9",
 							StartOffset: 6,
 							EndOffset:   9,
+
+							BuildConfiguration: "test-build-config",
 						},
 						Kind:   "/kythe/defines/binding",
 						Target: "kythe://c?lang=otpl?path=/a/path#map",
@@ -501,6 +503,23 @@ func TestDecorationsRefs(t *testing.T) {
 	}
 }
 
+func TestDecorationsBuildConfig(t *testing.T) {
+	d := tbl.Decorations[1]
+
+	st := tbl.Construct(t)
+	reply, err := st.Decorations(ctx, &xpb.DecorationsRequest{
+		Location:    &xpb.Location{Ticket: d.File.Ticket},
+		References:  true,
+		BuildConfig: []string{"test-build-config"},
+	})
+	testutil.FatalOnErrT(t, "DecorationsRequest error: %v", err)
+
+	expected := refs(span.NewNormalizer(d.File.Text), d.Decoration[:1])
+	if err := testutil.DeepEqual(expected, reply.Reference); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestDecorationsDirtyBuffer(t *testing.T) {
 	d := tbl.Decorations[1]
 
@@ -544,6 +563,8 @@ func TestDecorationsDirtyBuffer(t *testing.T) {
 					ColumnOffset: 9,
 				},
 			},
+
+			BuildConfig: "test-build-config",
 		},
 		// Skipped anchor for "empty?" (inside edit region)
 		{

kythe/proto/xref.proto

@@ -154,6 +154,11 @@ message DecorationsRequest {
 
   // What kind of snippets to return (or none).
   SnippetsKind snippets = 9;
+
+  // Set of build configurations with which to filter decorations.  If empty,
+  // no filtering based on build configs will be done; all decorations for the
+  // file will be returned.
+  repeated string build_config = 11;
 }
 
 message DecorationsReply {
@@ -179,6 +184,9 @@ message DecorationsReply {
     // The reference's span within the source file.
     common.Span span = 5;
 
+    // The build config of the file containing this reference.
+    string build_config = 6;
+
     reserved 1, 10, 11;
   }
 
@@ -216,6 +224,7 @@ message DecorationsReply {
 
   // If requested, a list of diagnostics applying to the requested file
   // location.
+  // TODO(schroederc): filter spanning diagnostics by build configuration
   repeated common.Diagnostic diagnostic = 5;
 
   // This field will contain one entry, keyed by ticket, for each distinct node