govim: make schedule more useful and fix TestDriver (#130)

.travis.yml

@@ -8,8 +8,8 @@ env:
   global:
     - GO111MODULE=on
   matrix:
-    - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1137 VIM_COMMAND="vim"
-    - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1137 VIM_COMMAND="xvfb-run -a gvim -f"
+    - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1158 VIM_COMMAND="vim"
+    - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1158 VIM_COMMAND="xvfb-run -a gvim -f"
     - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1176 VIM_COMMAND="vim"
     - GO_VERSION=go1.12.3 VIM_VERSION=v8.1.1176 VIM_COMMAND="xvfb-run -a gvim -f"
 

cmd/govim/main_test.go

@@ -36,7 +36,7 @@ func TestScripts(t *testing.T) {
 	var waitLock sync.Mutex
 	var waitList []func() error
 
-	td, err := ioutil.TempDir("", "gobin-gopls-installdir*")
+	td, err := ioutil.TempDir("", "gobin-gopls-installdir")
 	if err != nil {
 		t.Fatalf("failed to create temp install directory for gopls: %v", err)
 	}
@@ -64,6 +64,7 @@ func TestScripts(t *testing.T) {
 				if err != nil {
 					t.Fatalf("failed to create new driver: %v", err)
 				}
+				td.Log = os.Stderr
 				if *fLogGovim {
 					tf, err := ioutil.TempFile("", "govim_test_script_govim_log*")
 					if err != nil {

event_queue.go

@@ -47,7 +47,7 @@ func (e eventQueueInst) Scheduled() Govim {
 	return e
 }
 
-func (e eventQueueInst) Schedule(f func(Govim) error) {
+func (e eventQueueInst) Schedule(f func(Govim) error) chan struct{} {
 	panic(fmt.Errorf("attempt to schedule work on the event queue from the event queue itself"))
 }
 

govim.go

@@ -105,7 +105,7 @@ type Govim interface {
 	Scheduled() Govim
 
 	// Schedule schdules f to run in the event queue
-	Schedule(func(Govim) error)
+	Schedule(func(Govim) error) chan struct{}
 }
 
 type govimImpl struct {
@@ -132,7 +132,6 @@ type govimImpl struct {
 	loaded chan bool
 
 	currViewport             Viewport
-	viewportLock             sync.Mutex
 	onViewportChangeSubs     []*OnViewportChangeSub
 	onViewportChangeSubsLock sync.Mutex
 
@@ -182,10 +181,16 @@ func (g *govimImpl) Scheduled() Govim {
 	}
 }
 
-func (g *govimImpl) Schedule(f func(Govim) error) {
+func (g *govimImpl) Schedule(f func(Govim) error) chan struct{} {
+	done := make(chan struct{})
 	g.eventQueue.Add(func() error {
-		return f(g)
+		defer func() {
+			close(done)
+			g.flushEvents <- struct{}{}
+		}()
+		return f(g.Scheduled())
 	})
+	return done
 }
 
 func (g *govimImpl) load() error {

plugin/govim.vim

@@ -102,6 +102,7 @@ function s:define(channel, msg)
       let s:timer = timer_start(100, function('s:updateViewport'), {'repeat': -1})
       au CursorMoved,CursorMovedI,BufWinEnter * call s:updateViewport(0)
       let s:govim_status = "loaded"
+      call s:updateViewport(0)
       for F in s:loadStatusCallbacks
         call call(F, [s:govim_status])
       endfor

testdriver/testdriver.go

@@ -278,21 +278,36 @@ func (d *TestDriver) listenDriver() error {
 				if len(args) == 2 {
 					force = args[1].(string)
 				}
-				add(d.govim.ChannelRedraw(force == "force"))
+				<-d.govim.Schedule(func(g govim.Govim) error {
+					add(g.ChannelRedraw(force == "force"))
+					return nil
+				})
 			case "ex":
 				expr := args[1].(string)
-				add(d.govim.ChannelEx(expr))
+				<-d.govim.Schedule(func(g govim.Govim) error {
+					add(g.ChannelEx(expr))
+					return nil
+				})
 			case "normal":
 				expr := args[1].(string)
-				add(d.govim.ChannelNormal(expr))
+				<-d.govim.Schedule(func(g govim.Govim) error {
+					add(g.ChannelNormal(expr))
+					return nil
+				})
 			case "expr":
 				expr := args[1].(string)
-				resp, err := d.govim.ChannelExpr(expr)
-				add(err, resp)
+				<-d.govim.Schedule(func(g govim.Govim) error {
+					resp, err := g.ChannelExpr(expr)
+					add(err, resp)
+					return nil
+				})
 			case "call":
 				fn := args[1].(string)
-				resp, err := d.govim.ChannelCall(fn, args[2:]...)
-				add(err, resp)
+				<-d.govim.Schedule(func(g govim.Govim) error {
+					resp, err := g.ChannelCall(fn, args[2:]...)
+					add(err, resp)
+					return nil
+				})
 			default:
 				panic(fmt.Errorf("don't yet know how to handle %v", cmd))
 			}

viewport.go

@@ -53,10 +53,8 @@ type OnViewportChangeSub struct {
 func (g *govimImpl) onViewportChange(args ...json.RawMessage) (interface{}, error) {
 	var r Viewport
 	g.decodeJSON(args[0], &r)
-	g.viewportLock.Lock()
 	g.currViewport = r
 	r = r.dup()
-	g.viewportLock.Unlock()
 
 	g.Logf("Viewport changed: %v", pretty.Sprint(r))
 
@@ -96,11 +94,7 @@ type WinInfo struct {
 
 // Viewport returns the active Vim viewport
 func (g *govimImpl) Viewport() Viewport {
-	var res Viewport
-	g.viewportLock.Lock()
-	res = g.currViewport.dup()
-	g.viewportLock.Unlock()
-	return res
+	return g.currViewport.dup()
 }
 
 func (v Viewport) dup() Viewport {