internal/lsp: fix label completion in range and type switch stmts

Fix label detection to know about *ast.RangeStmt
and *ast.TypeSwitchStmt.

Change-Id: I4061e165884f7064fe486249fe3664d572b7b628
Reviewed-on: https://go-review.googlesource.com/c/tools/+/202621
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

internal/lsp/source/completion_labels.go

@@ -71,10 +71,10 @@ func (c *completer) labels(lt labelType) {
 				return
 			case *ast.LabeledStmt:
 				switch p.Stmt.(type) {
-				case *ast.ForStmt:
+				case *ast.ForStmt, *ast.RangeStmt:
 					// Loop labels can be used for "break" or "continue".
 					addLabel(p)
-				case *ast.SwitchStmt, *ast.SelectStmt:
+				case *ast.SwitchStmt, *ast.SelectStmt, *ast.TypeSwitchStmt:
 					// Switch and select labels can be used only for "break".
 					if lt == labelBreak {
 						addLabel(p)

internal/lsp/testdata/labels/labels.go

@@ -1,10 +1,10 @@
 package labels
 
 func _() {
-	goto F //@complete(" //", label1, label4)
+	goto F //@complete(" //", label1, label5)
 
 Foo1: //@item(label1, "Foo1", "label", "const")
-	for {
+	for a, b := range []int{} {
 	Foo2: //@item(label2, "Foo2", "label", "const")
 		switch {
 		case true:
@@ -16,7 +16,7 @@ Foo1: //@item(label1, "Foo1", "label", "const")
 			FooUnjumpable:
 			}
 
-			goto F //@complete(" //", label1, label2, label4)
+			goto F //@complete(" //", label1, label2, label4, label5)
 
 			func() {
 				goto F //@complete(" //", label3)
@@ -28,12 +28,22 @@ Foo1: //@item(label1, "Foo1", "label", "const")
 			Foo3: //@item(label3, "Foo3", "label", "const")
 			}()
 		}
+
+	Foo4: //@item(label4, "Foo4", "label", "const")
+		switch interface{}(a).(type) {
+		case int:
+			break F //@complete(" //", label4, label1)
+		}
 	}
 
 	break F //@complete(" //")
 
 	continue F //@complete(" //")
 
-Foo4: //@item(label4, "Foo4", "label", "const")
+Foo5: //@item(label5, "Foo5", "label", "const")
+	for {
+		break F //@complete(" //", label5)
+	}
+
 	return
 }

internal/lsp/testdata/summary.txt.golden

@@ -1,5 +1,5 @@
 -- summary --
-CompletionsCount = 209
+CompletionsCount = 211
 CompletionSnippetCount = 39
 UnimportedCompletionsCount = 1
 DeepCompletionsCount = 5