Merge branch 'master' into optionalChainingStage3

src/compiler/binder.ts

@@ -1079,7 +1079,7 @@ namespace ts {
 
         function bindCondition(node: Expression | undefined, trueTarget: FlowLabel, falseTarget: FlowLabel) {
             doWithConditionalBranches(bind, node, trueTarget, falseTarget);
-            if (!node || !isLogicalExpression(node)) {
+            if (!node || !isLogicalExpression(node) && !(isOptionalChain(node) && isOutermostOptionalChain(node))) {
                 addAntecedent(trueTarget, createFlowCondition(FlowFlags.TrueCondition, currentFlow, node));
                 addAntecedent(falseTarget, createFlowCondition(FlowFlags.FalseCondition, currentFlow, node));
             }

src/compiler/debug.ts

@@ -303,7 +303,7 @@ namespace ts {
                 udl = "┤",
                 dlr = "┬",
                 ulr = "┴",
-                udlr = "┼",
+                udlr = "╫",
             }
 
             const enum Connection {
@@ -415,12 +415,8 @@ namespace ts {
                     nodes.push(graphNode);
                     if (!(flowNode.flags & FlowFlags.PreFinally)) {
                         if (hasAntecedents(flowNode)) {
-                            // sort antecedents so that shallower trees come first.
-                            const antecedents = flowNode.antecedents;
-                            const heights = antecedents.map(measureHeight);
-                            const indices = antecedents.map((_, i) => i);
-                            stableSortIndices(heights, indices, (a, b) => b - a);
-                            for (const antecedent of indices.map(i => antecedents[i])) {
+
+                            for (const antecedent of flowNode.antecedents) {
                                 buildGraphEdge(graphNode, antecedent);
                             }
                         }
@@ -451,12 +447,6 @@ namespace ts {
                 return node.level = level;
             }
 
-            function measureHeight(flowNode: FlowNode): number {
-                return hasAntecedents(flowNode) ? flowNode.antecedents.reduce((x, n) => Math.max(x, measureHeight(n)), 0) + 1 :
-                    hasAntecedent(flowNode) ? measureHeight(flowNode.antecedent) + 1 :
-                    1;
-            }
-
             function computeHeight(node: FlowGraphNode): number {
                 let height = 0;
                 for (const child of getChildren(node)) {