Function bindTryStatement

test/fixtures/snapshot/typescript.js:45670–45746

(node)

            }
        }
        function bindTryStatement(node) {
            // We conservatively assume that *any* code in the try block can cause an exception, but we only need
            // to track code that causes mutations (because only mutations widen the possible control flow type of
            // a variable). The exceptionLabel is the target label for control flows that result from exceptions.
            // We add all mutation flow nodes as antecedents of this label such that we can analyze them as possible
            // antecedents of the start of catch or finally blocks. Furthermore, we add the current control flow to
            // represent exceptions that occur before any mutations.
            var saveReturnTarget = currentReturnTarget;
            var saveExceptionTarget = currentExceptionTarget;
            var normalExitLabel = createBranchLabel();
            var returnLabel = createBranchLabel();
            var exceptionLabel = createBranchLabel();
            if (node.finallyBlock) {
                currentReturnTarget = returnLabel;
            }
            addAntecedent(exceptionLabel, currentFlow);
            currentExceptionTarget = exceptionLabel;
            bind(node.tryBlock);
            addAntecedent(normalExitLabel, currentFlow);
            if (node.catchClause) {
                // Start of catch clause is the target of exceptions from try block.
                currentFlow = finishFlowLabel(exceptionLabel);
                // The currentExceptionTarget now represents control flows from exceptions in the catch clause.
                // Effectively, in a try-catch-finally, if an exception occurs in the try block, the catch block
                // acts like a second try block.
                exceptionLabel = createBranchLabel();
                addAntecedent(exceptionLabel, currentFlow);
                currentExceptionTarget = exceptionLabel;
                bind(node.catchClause);
                addAntecedent(normalExitLabel, currentFlow);
            }
            currentReturnTarget = saveReturnTarget;
            currentExceptionTarget = saveExceptionTarget;
            if (node.finallyBlock) {
                // Possible ways control can reach the finally block:
                // 1) Normal completion of try block of a try-finally or try-catch-finally
                // 2) Normal completion of catch block (following exception in try block) of a try-catch-finally
                // 3) Return in try or catch block of a try-finally or try-catch-finally
                // 4) Exception in try block of a try-finally
                // 5) Exception in catch block of a try-catch-finally
                // When analyzing a control flow graph that starts inside a finally block we want to consider all
                // five possibilities above. However, when analyzing a control flow graph that starts outside (past)
                // the finally block, we only want to consider the first two (if we're past a finally block then it
                // must have completed normally). Likewise, when analyzing a control flow graph from return statements
                // in try or catch blocks in an IIFE, we only want to consider the third. To make this possible, we
                // inject a ReduceLabel node into the control flow graph. This node contains an alternate reduced
                // set of antecedents for the pre-finally label. As control flow analysis passes by a ReduceLabel
                // node, the pre-finally label is temporarily switched to the reduced antecedent set.
                var finallyLabel = createBranchLabel();
                finallyLabel.antecedents = ts.concatenate(ts.concatenate(normalExitLabel.antecedents, exceptionLabel.antecedents), returnLabel.antecedents);
                currentFlow = finallyLabel;
                bind(node.finallyBlock);
                if (currentFlow.flags & 1 /* FlowFlags.Unreachable */) {
                    // If the end of the finally block is unreachable, the end of the entire try statement is unreachable.
                    currentFlow = unreachableFlow;
                }
                else {
                    // If we have an IIFE return target and return statements in the try or catch blocks, add a control