service/dap: send InvalidatedEvent after SetVariable and WriteMemory

service/dap/daptest/client.go

@@ -231,6 +231,8 @@ func (c *Client) InitializeRequest() {
 		SupportsVariablePaging:       true,
 		SupportsRunInTerminalRequest: true,
 		SupportsMemoryReferences:     true,
+		SupportsMemoryEvent:          true,
+		SupportsInvalidatedEvent:     true,
 		Locale:                       "en-us",
 	}
 	c.send(request)

service/dap/server.go

@@ -337,6 +337,8 @@ type dapClientCapabilities struct {
 	supportsRunInTerminalRequest bool
 	supportsMemoryReferences     bool
 	supportsProgressReporting    bool
+	supportsMemoryEvent          bool
+	supportsInvalidatedEvent     bool
 }
 
 // DefaultLoadConfig controls how variables are loaded from the target's memory.
@@ -994,6 +996,8 @@ func (s *Session) setClientCapabilities(args dap.InitializeRequestArguments) {
 	s.clientCapabilities.supportsRunInTerminalRequest = args.SupportsRunInTerminalRequest
 	s.clientCapabilities.supportsVariablePaging = args.SupportsVariablePaging
 	s.clientCapabilities.supportsVariableType = args.SupportsVariableType
+	s.clientCapabilities.supportsMemoryEvent = args.SupportsMemoryEvent
+	s.clientCapabilities.supportsInvalidatedEvent = args.SupportsInvalidatedEvent
 }
 
 func cleanExeName(name string) string {
@@ -3652,6 +3656,17 @@ func (s *Session) onSetVariableRequest(request *dap.SetVariableRequest) {
 	// TODO(hyangah): instead of arg.Value, reload the variable and return
 	// the presentation of the new value.
 	s.send(response)
+
+	if s.clientCapabilities.supportsInvalidatedEvent {
+		// Enforce editors to reload full state after successfull variable update
+		// to fix problem described above
+		s.send(&dap.InvalidatedEvent{
+			Event: *s.newEvent("invalidated"),
+			Body: dap.InvalidatedEventBody{
+				Areas: []dap.InvalidatedAreas{"all"},
+			},
+		})
+	}
 }
 
 // onSetExpressionRequest sends a not-yet-implemented error response.
@@ -3788,6 +3803,16 @@ func (s *Session) onWriteMemoryRequest(request *dap.WriteMemoryRequest) {
 			BytesWritten: n,
 		},
 	})
+
+	if s.clientCapabilities.supportsInvalidatedEvent {
+		// Inform editor to refetch variables after changes
+		s.send(&dap.InvalidatedEvent{
+			Event: *s.newEvent("invalidated"),
+			Body: dap.InvalidatedEventBody{
+				Areas: []dap.InvalidatedAreas{"variables"},
+			},
+		})
+	}
 }
 
 func (s *Session) writeTargetMemory(addr uint64, data []byte) (int, error) {

service/dap/server_test.go

@@ -6636,6 +6636,10 @@ func (h *helperForSetVariable) expectSetVariable0(ref int, name, value string, w
 	if got, want := h.c.ExpectSetVariableResponse(h.t), value; got.Success != true || got.Body.Value != want {
 		h.t.Errorf("SetVariableRequest(%v, %v)=%#v, want {Success=true, Body.Value=%q", name, value, got, want)
 	}
+	ie := h.c.ExpectInvalidatedEvent(h.t)
+	if len(ie.Body.Areas) != 1 && ie.Body.Areas[0] != "all" {
+		h.t.Errorf("expected 'all' invalidated areas, got %v", ie.Body.Areas)
+	}
 }
 
 func (h *helperForSetVariable) failSetVariable0(ref int, name, value, wantErrInfo string, wantStop bool) {
@@ -8596,6 +8600,10 @@ func TestWriteMemory(t *testing.T) {
 						if wr.Body.BytesWritten != len(newData) {
 							t.Fatalf("expected %d bytes written, got %d", len(newData), wr.Body.BytesWritten)
 						}
+						ie := client.ExpectInvalidatedEvent(t)
+						if len(ie.Body.Areas) != 1 && ie.Body.Areas[0] != "variables" {
+							t.Fatalf("expected 'varianles' invalidated areas, got %v", ie.Body.Areas)
+						}
 
 						client.ReadMemoryRequest(bytesVar.MemoryReference, 0, len(newData))
 						rm = client.ExpectReadMemoryResponse(t)
@@ -8612,6 +8620,10 @@ func TestWriteMemory(t *testing.T) {
 						if wr.Body.BytesWritten != len(origData) {
 							t.Fatalf("expected %d bytes written, got %d", len(newData), wr.Body.BytesWritten)
 						}
+						ie = client.ExpectInvalidatedEvent(t)
+						if len(ie.Body.Areas) != 1 && ie.Body.Areas[0] != "variables" {
+							t.Fatalf("expected 'variables' invalidated areas, got %v", ie.Body.Areas)
+						}
 					},
 					disconnect: true,
 				},