diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 96a783a6c9e73..7c6336276f90a 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -18787,6 +18787,14 @@ namespace ts {
                 signature.declaration && (getReturnTypeFromAnnotation(signature.declaration) || unknownType).flags & TypeFlags.Never);
         }
 
+        function getTypePredicateArgument(predicate: TypePredicate, callExpression: CallExpression) {
+            if (predicate.kind === TypePredicateKind.Identifier || predicate.kind === TypePredicateKind.AssertsIdentifier) {
+                return callExpression.arguments[predicate.parameterIndex];
+            }
+            const invokedExpression = skipParentheses(callExpression.expression);
+            return isAccessExpression(invokedExpression) ? skipParentheses(invokedExpression.expression) : undefined;
+        }
+
         function reportFlowControlError(node: Node) {
             const block = <Block | ModuleBlock | SourceFile>findAncestor(node, isFunctionOrModuleBlock);
             const sourceFile = getSourceFileOfNode(node);
@@ -19175,20 +19183,30 @@ namespace ts {
                 if (isMatchingReference(reference, expr)) {
                     type = narrowTypeBySwitchOnDiscriminant(type, flow.switchStatement, flow.clauseStart, flow.clauseEnd);
                 }
-                else if (isMatchingReferenceDiscriminant(expr, type)) {
-                    type = narrowTypeByDiscriminant(
-                        type,
-                        expr as AccessExpression,
-                        t => narrowTypeBySwitchOnDiscriminant(t, flow.switchStatement, flow.clauseStart, flow.clauseEnd));
-                }
                 else if (expr.kind === SyntaxKind.TypeOfExpression && isMatchingReference(reference, (expr as TypeOfExpression).expression)) {
                     type = narrowBySwitchOnTypeOf(type, flow.switchStatement, flow.clauseStart, flow.clauseEnd);
                 }
-                else if (containsMatchingReferenceDiscriminant(reference, expr)) {
-                    type = declaredType;
-                }
-                else if (flow.clauseStart === flow.clauseEnd && isExhaustiveSwitchStatement(flow.switchStatement)) {
-                    return unreachableNeverType;
+                else {
+                    if (strictNullChecks) {
+                        if (optionalChainContainsReference(expr, reference)) {
+                            type = narrowTypeBySwitchOptionalChainContainment(type, flow.switchStatement, flow.clauseStart, flow.clauseEnd,
+                                t => !(t.flags & (TypeFlags.Undefined | TypeFlags.Never)));
+                        }
+                        else if (expr.kind === SyntaxKind.TypeOfExpression && optionalChainContainsReference((expr as TypeOfExpression).expression, reference)) {
+                            type = narrowTypeBySwitchOptionalChainContainment(type, flow.switchStatement, flow.clauseStart, flow.clauseEnd,
+                                t => !(t.flags & TypeFlags.Never || t.flags & TypeFlags.StringLiteral && (<StringLiteralType>t).value === "undefined"));
+                        }
+                    }
+                    if (isMatchingReferenceDiscriminant(expr, type)) {
+                        type = narrowTypeByDiscriminant(type, expr as AccessExpression,
+                            t => narrowTypeBySwitchOnDiscriminant(t, flow.switchStatement, flow.clauseStart, flow.clauseEnd));
+                    }
+                    else if (containsMatchingReferenceDiscriminant(reference, expr)) {
+                        type = declaredType;
+                    }
+                    else if (flow.clauseStart === flow.clauseEnd && isExhaustiveSwitchStatement(flow.switchStatement)) {
+                        return unreachableNeverType;
+                    }
                 }
                 return createFlowType(type, isIncomplete(flowType));
             }
@@ -19333,6 +19351,9 @@ namespace ts {
                 if (isMatchingReference(reference, expr)) {
                     return getTypeWithFacts(type, assumeTrue ? TypeFacts.Truthy : TypeFacts.Falsy);
                 }
+                if (strictNullChecks && assumeTrue && optionalChainContainsReference(expr, reference)) {
+                    type = getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull);
+                }
                 if (isMatchingReferenceDiscriminant(expr, declaredType)) {
                     return narrowTypeByDiscriminant(type, <AccessExpression>expr, t => getTypeWithFacts(t, assumeTrue ? TypeFacts.Truthy : TypeFacts.Falsy));
                 }
@@ -19384,12 +19405,12 @@ namespace ts {
                         if (isMatchingReference(reference, right)) {
                             return narrowTypeByEquality(type, operator, left, assumeTrue);
                         }
-                        if (assumeTrue && strictNullChecks) {
+                        if (strictNullChecks) {
                             if (optionalChainContainsReference(left, reference)) {
-                                type = narrowTypeByOptionalChainContainment(type, operator, right);
+                                type = narrowTypeByOptionalChainContainment(type, operator, right, assumeTrue);
                             }
                             else if (optionalChainContainsReference(right, reference)) {
-                                type = narrowTypeByOptionalChainContainment(type, operator, left);
+                                type = narrowTypeByOptionalChainContainment(type, operator, left, assumeTrue);
                             }
                         }
                         if (isMatchingReferenceDiscriminant(left, declaredType)) {
@@ -19416,16 +19437,14 @@ namespace ts {
                 return type;
             }
 
-            function narrowTypeByOptionalChainContainment(type: Type, operator: SyntaxKind, value: Expression): Type {
-                // We are in the true branch of obj?.foo === value or obj?.foo !== value. We remove undefined and null from
+            function narrowTypeByOptionalChainContainment(type: Type, operator: SyntaxKind, value: Expression, assumeTrue: boolean): Type {
+                // We are in a branch of obj?.foo === value or obj?.foo !== value. We remove undefined and null from
                 // the type of obj if (a) the operator is === and the type of value doesn't include undefined or (b) the
                 // operator is !== and the type of value is undefined.
-                const valueType = getTypeOfExpression(value);
-                return operator === SyntaxKind.EqualsEqualsToken && !(getTypeFacts(valueType) & TypeFacts.EQUndefinedOrNull) ||
-                    operator === SyntaxKind.EqualsEqualsEqualsToken && !(getTypeFacts(valueType) & TypeFacts.EQUndefined) ||
-                    operator === SyntaxKind.ExclamationEqualsToken && valueType.flags & TypeFlags.Nullable ||
-                    operator === SyntaxKind.ExclamationEqualsEqualsToken && valueType.flags & TypeFlags.Undefined ?
-                    getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull) : type;
+                const effectiveTrue = operator === SyntaxKind.EqualsEqualsToken || operator === SyntaxKind.EqualsEqualsEqualsToken ? assumeTrue : !assumeTrue;
+                const doubleEquals = operator === SyntaxKind.EqualsEqualsToken || operator === SyntaxKind.ExclamationEqualsToken;
+                const valueNonNullish = !(getTypeFacts(getTypeOfExpression(value)) & (doubleEquals ? TypeFacts.EQUndefinedOrNull : TypeFacts.EQUndefined));
+                return effectiveTrue === valueNonNullish ? getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull) : type;
             }
 
             function narrowTypeByEquality(type: Type, operator: SyntaxKind, value: Expression, assumeTrue: boolean): Type {
@@ -19476,10 +19495,12 @@ namespace ts {
 
             function narrowTypeByTypeof(type: Type, typeOfExpr: TypeOfExpression, operator: SyntaxKind, literal: LiteralExpression, assumeTrue: boolean): Type {
                 // We have '==', '!=', '===', or !==' operator with 'typeof xxx' and string literal operands
+                if (operator === SyntaxKind.ExclamationEqualsToken || operator === SyntaxKind.ExclamationEqualsEqualsToken) {
+                    assumeTrue = !assumeTrue;
+                }
                 const target = getReferenceCandidate(typeOfExpr.expression);
                 if (!isMatchingReference(reference, target)) {
-                    if (assumeTrue && (operator === SyntaxKind.EqualsEqualsToken || operator === SyntaxKind.EqualsEqualsEqualsToken) &&
-                        strictNullChecks && optionalChainContainsReference(target, reference)) {
+                    if (strictNullChecks && optionalChainContainsReference(target, reference) && assumeTrue === (literal.text !== "undefined")) {
                         return getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull);
                     }
                     // For a reference of the form 'x.y', a 'typeof x === ...' type guard resets the
@@ -19489,9 +19510,6 @@ namespace ts {
                     }
                     return type;
                 }
-                if (operator === SyntaxKind.ExclamationEqualsToken || operator === SyntaxKind.ExclamationEqualsEqualsToken) {
-                    assumeTrue = !assumeTrue;
-                }
                 if (type.flags & TypeFlags.Any && literal.text === "function") {
                     return type;
                 }
@@ -19526,6 +19544,11 @@ namespace ts {
                 }
             }
 
+            function narrowTypeBySwitchOptionalChainContainment(type: Type, switchStatement: SwitchStatement, clauseStart: number, clauseEnd: number, clauseCheck: (type: Type) => boolean) {
+                const everyClauseChecks = clauseStart !== clauseEnd && every(getSwitchClauseTypes(switchStatement).slice(clauseStart, clauseEnd), clauseCheck);
+                return everyClauseChecks ? getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull) : type;
+            }
+
             function narrowTypeBySwitchOnDiscriminant(type: Type, switchStatement: SwitchStatement, clauseStart: number, clauseEnd: number) {
                 // We only narrow if all case expressions specify
                 // values with unit types, except for the case where
@@ -19746,28 +19769,17 @@ namespace ts {
 
             function narrowTypeByTypePredicate(type: Type, predicate: TypePredicate, callExpression: CallExpression, assumeTrue: boolean): Type {
                 // Don't narrow from 'any' if the predicate type is exactly 'Object' or 'Function'
-                if (isTypeAny(type) && (predicate.type === globalObjectType || predicate.type === globalFunctionType)) {
-                    return type;
-                }
-                if (predicate.kind === TypePredicateKind.Identifier || predicate.kind === TypePredicateKind.AssertsIdentifier) {
-                    const predicateArgument = callExpression.arguments[predicate.parameterIndex];
-                    if (predicateArgument && predicate.type) {
+                if (predicate.type && !(isTypeAny(type) && (predicate.type === globalObjectType || predicate.type === globalFunctionType))) {
+                    const predicateArgument = getTypePredicateArgument(predicate, callExpression);
+                    if (predicateArgument) {
                         if (isMatchingReference(reference, predicateArgument)) {
                             return getNarrowedType(type, predicate.type, assumeTrue, isTypeSubtypeOf);
                         }
-                        if (containsMatchingReference(reference, predicateArgument)) {
-                            return declaredType;
-                        }
-                    }
-                }
-                else {
-                    const invokedExpression = skipParentheses(callExpression.expression);
-                    if (isAccessExpression(invokedExpression) && predicate.type) {
-                        const possibleReference = skipParentheses(invokedExpression.expression);
-                        if (isMatchingReference(reference, possibleReference)) {
-                            return getNarrowedType(type, predicate.type, assumeTrue, isTypeSubtypeOf);
+                        if (strictNullChecks && assumeTrue && optionalChainContainsReference(predicateArgument, reference) &&
+                            !(getTypeFacts(predicate.type) & TypeFacts.EQUndefined)) {
+                            return getTypeWithFacts(type, TypeFacts.NEUndefinedOrNull);
                         }
-                        if (containsMatchingReference(reference, possibleReference)) {
+                        if (containsMatchingReference(reference, predicateArgument)) {
                             return declaredType;
                         }
                     }
diff --git a/tests/baselines/reference/controlFlowOptionalChain.errors.txt b/tests/baselines/reference/controlFlowOptionalChain.errors.txt
index 987dca335dccc..ee77494d1c828 100644
--- a/tests/baselines/reference/controlFlowOptionalChain.errors.txt
+++ b/tests/baselines/reference/controlFlowOptionalChain.errors.txt
@@ -31,9 +31,29 @@ tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(244,9): error TS
 tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(271,9): error TS2532: Object is possibly 'undefined'.
 tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(274,9): error TS2532: Object is possibly 'undefined'.
 tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(277,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(307,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(310,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(319,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(322,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(331,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(340,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(343,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(352,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(391,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(394,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(403,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(406,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(415,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(424,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(427,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(436,9): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(471,13): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(474,13): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(488,13): error TS2532: Object is possibly 'undefined'.
+tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(491,13): error TS2532: Object is possibly 'undefined'.
 
 
-==== tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts (33 errors) ====
+==== tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts (53 errors) ====
     // assignments in shortcutting chain
     declare const o: undefined | {
         [key: string]: any;
@@ -401,6 +421,76 @@ tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(277,9): error TS
         }
     }
     
+    function f15(o: Thing | undefined, value: number) {
+        if (o?.foo === value) {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (o?.foo !== value) {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (o?.foo == value) {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (o?.foo != value) {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+    }
+    
+    function f16(o: Thing | undefined) {
+        if (o?.foo === undefined) {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (o?.foo !== undefined) {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (o?.foo == undefined) {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (o?.foo != undefined) {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+    }
+    
     function f20(o: Thing | undefined) {
         if (typeof o?.foo === "number") {
             o.foo;
@@ -430,4 +520,171 @@ tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts(277,9): error TS
             o.baz;
         }
     }
+    
+    function f22(o: Thing | undefined) {
+        if (typeof o?.foo === "number") {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (typeof o?.foo !== "number") {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (typeof o?.foo == "number") {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (typeof o?.foo != "number") {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+    }
+    
+    function f23(o: Thing | undefined) {
+        if (typeof o?.foo === "undefined") {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (typeof o?.foo !== "undefined") {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        if (typeof o?.foo == "undefined") {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+        else {
+            o.foo;
+        }
+        if (typeof o?.foo != "undefined") {
+            o.foo;
+        }
+        else {
+            o.foo;  // Error
+            ~
+!!! error TS2532: Object is possibly 'undefined'.
+        }
+    }
+    
+    declare function assert(x: unknown): asserts x;
+    declare function assertNonNull<T>(x: T): asserts x is NonNullable<T>;
+    
+    function f30(o: Thing | undefined) {
+        if (!!true) {
+            assert(o?.foo);
+            o.foo;
+        }
+        if (!!true) {
+            assert(o?.foo === 42);
+            o.foo;
+        }
+        if (!!true) {
+            assert(typeof o?.foo === "number");
+            o.foo;
+        }
+        if (!!true) {
+            assertNonNull(o?.foo);
+            o.foo;
+        }
+    }
+    
+    function f40(o: Thing | undefined) {
+        switch (o?.foo) {
+            case "abc":
+                o.foo;
+                break;
+            case 42:
+                o.foo;
+                break;
+            case undefined:
+                o.foo;  // Error
+                ~
+!!! error TS2532: Object is possibly 'undefined'.
+                break;
+            default:
+                o.foo;  // Error
+                ~
+!!! error TS2532: Object is possibly 'undefined'.
+                break;
+        }
+    }
+    
+    function f41(o: Thing | undefined) {
+        switch (typeof o?.foo) {
+            case "string":
+                o.foo;
+                break;
+            case "number":
+                o.foo;
+                break;
+            case "undefined":
+                o.foo;  // Error
+                ~
+!!! error TS2532: Object is possibly 'undefined'.
+                break;
+            default:
+                o.foo;  // Error
+                ~
+!!! error TS2532: Object is possibly 'undefined'.
+                break;
+        }
+    }
+    
+    // Repros from #34570
+    
+    type Shape =
+        | { type: 'rectangle', width: number, height: number }
+        | { type: 'circle', radius: number }
+    
+    function getArea(shape?: Shape) {
+        switch (shape?.type) {
+            case 'circle':
+                return Math.PI * shape.radius ** 2
+            case 'rectangle':
+                return shape.width * shape.height
+            default:
+                return 0
+        }
+    }
+    
+    type Feature = {
+      id: string;
+      geometry?: {
+        type: string;
+        coordinates: number[];
+      };
+    };
+    
+    
+    function extractCoordinates(f: Feature): number[] {
+        if (f.geometry?.type !== 'test') {
+            return [];
+        }
+        return f.geometry.coordinates;
+    }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/controlFlowOptionalChain.js b/tests/baselines/reference/controlFlowOptionalChain.js
index 214515280350b..3bb2bab1c0dd3 100644
--- a/tests/baselines/reference/controlFlowOptionalChain.js
+++ b/tests/baselines/reference/controlFlowOptionalChain.js
@@ -300,6 +300,60 @@ function f14(o: Thing | null) {
     }
 }
 
+function f15(o: Thing | undefined, value: number) {
+    if (o?.foo === value) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo !== value) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo == value) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo != value) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+}
+
+function f16(o: Thing | undefined) {
+    if (o?.foo === undefined) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo !== undefined) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo == undefined) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo != undefined) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+}
+
 function f20(o: Thing | undefined) {
     if (typeof o?.foo === "number") {
         o.foo;
@@ -329,6 +383,149 @@ function f21(o: Thing | null) {
         o.baz;
     }
 }
+
+function f22(o: Thing | undefined) {
+    if (typeof o?.foo === "number") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo !== "number") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo == "number") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo != "number") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+}
+
+function f23(o: Thing | undefined) {
+    if (typeof o?.foo === "undefined") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo !== "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo == "undefined") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo != "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+}
+
+declare function assert(x: unknown): asserts x;
+declare function assertNonNull<T>(x: T): asserts x is NonNullable<T>;
+
+function f30(o: Thing | undefined) {
+    if (!!true) {
+        assert(o?.foo);
+        o.foo;
+    }
+    if (!!true) {
+        assert(o?.foo === 42);
+        o.foo;
+    }
+    if (!!true) {
+        assert(typeof o?.foo === "number");
+        o.foo;
+    }
+    if (!!true) {
+        assertNonNull(o?.foo);
+        o.foo;
+    }
+}
+
+function f40(o: Thing | undefined) {
+    switch (o?.foo) {
+        case "abc":
+            o.foo;
+            break;
+        case 42:
+            o.foo;
+            break;
+        case undefined:
+            o.foo;  // Error
+            break;
+        default:
+            o.foo;  // Error
+            break;
+    }
+}
+
+function f41(o: Thing | undefined) {
+    switch (typeof o?.foo) {
+        case "string":
+            o.foo;
+            break;
+        case "number":
+            o.foo;
+            break;
+        case "undefined":
+            o.foo;  // Error
+            break;
+        default:
+            o.foo;  // Error
+            break;
+    }
+}
+
+// Repros from #34570
+
+type Shape =
+    | { type: 'rectangle', width: number, height: number }
+    | { type: 'circle', radius: number }
+
+function getArea(shape?: Shape) {
+    switch (shape?.type) {
+        case 'circle':
+            return Math.PI * shape.radius ** 2
+        case 'rectangle':
+            return shape.width * shape.height
+        default:
+            return 0
+    }
+}
+
+type Feature = {
+  id: string;
+  geometry?: {
+    type: string;
+    coordinates: number[];
+  };
+};
+
+
+function extractCoordinates(f: Feature): number[] {
+    if (f.geometry?.type !== 'test') {
+        return [];
+    }
+    return f.geometry.coordinates;
+}
 
 
 //// [controlFlowOptionalChain.js]
@@ -594,6 +791,60 @@ function f14(o) {
         o.bar;
     }
 }
+function f15(o, value) {
+    var _a, _b, _c, _d;
+    if (((_a = o) === null || _a === void 0 ? void 0 : _a.foo) === value) {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (((_b = o) === null || _b === void 0 ? void 0 : _b.foo) !== value) {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (((_c = o) === null || _c === void 0 ? void 0 : _c.foo) == value) {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (((_d = o) === null || _d === void 0 ? void 0 : _d.foo) != value) {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+}
+function f16(o) {
+    var _a, _b, _c, _d;
+    if (((_a = o) === null || _a === void 0 ? void 0 : _a.foo) === undefined) {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (((_b = o) === null || _b === void 0 ? void 0 : _b.foo) !== undefined) {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (((_c = o) === null || _c === void 0 ? void 0 : _c.foo) == undefined) {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (((_d = o) === null || _d === void 0 ? void 0 : _d.foo) != undefined) {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+}
 function f20(o) {
     var _a, _b, _c, _d;
     if (typeof ((_a = o) === null || _a === void 0 ? void 0 : _a.foo) === "number") {
@@ -624,3 +875,128 @@ function f21(o) {
         o.baz;
     }
 }
+function f22(o) {
+    var _a, _b, _c, _d;
+    if (typeof ((_a = o) === null || _a === void 0 ? void 0 : _a.foo) === "number") {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (typeof ((_b = o) === null || _b === void 0 ? void 0 : _b.foo) !== "number") {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof ((_c = o) === null || _c === void 0 ? void 0 : _c.foo) == "number") {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (typeof ((_d = o) === null || _d === void 0 ? void 0 : _d.foo) != "number") {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+}
+function f23(o) {
+    var _a, _b, _c, _d;
+    if (typeof ((_a = o) === null || _a === void 0 ? void 0 : _a.foo) === "undefined") {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof ((_b = o) === null || _b === void 0 ? void 0 : _b.foo) !== "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+    if (typeof ((_c = o) === null || _c === void 0 ? void 0 : _c.foo) == "undefined") {
+        o.foo; // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof ((_d = o) === null || _d === void 0 ? void 0 : _d.foo) != "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo; // Error
+    }
+}
+function f30(o) {
+    var _a, _b, _c, _d;
+    if (!!true) {
+        assert((_a = o) === null || _a === void 0 ? void 0 : _a.foo);
+        o.foo;
+    }
+    if (!!true) {
+        assert(((_b = o) === null || _b === void 0 ? void 0 : _b.foo) === 42);
+        o.foo;
+    }
+    if (!!true) {
+        assert(typeof ((_c = o) === null || _c === void 0 ? void 0 : _c.foo) === "number");
+        o.foo;
+    }
+    if (!!true) {
+        assertNonNull((_d = o) === null || _d === void 0 ? void 0 : _d.foo);
+        o.foo;
+    }
+}
+function f40(o) {
+    var _a;
+    switch ((_a = o) === null || _a === void 0 ? void 0 : _a.foo) {
+        case "abc":
+            o.foo;
+            break;
+        case 42:
+            o.foo;
+            break;
+        case undefined:
+            o.foo; // Error
+            break;
+        default:
+            o.foo; // Error
+            break;
+    }
+}
+function f41(o) {
+    var _a;
+    switch (typeof ((_a = o) === null || _a === void 0 ? void 0 : _a.foo)) {
+        case "string":
+            o.foo;
+            break;
+        case "number":
+            o.foo;
+            break;
+        case "undefined":
+            o.foo; // Error
+            break;
+        default:
+            o.foo; // Error
+            break;
+    }
+}
+function getArea(shape) {
+    var _a;
+    switch ((_a = shape) === null || _a === void 0 ? void 0 : _a.type) {
+        case 'circle':
+            return Math.PI * Math.pow(shape.radius, 2);
+        case 'rectangle':
+            return shape.width * shape.height;
+        default:
+            return 0;
+    }
+}
+function extractCoordinates(f) {
+    var _a;
+    if (((_a = f.geometry) === null || _a === void 0 ? void 0 : _a.type) !== 'test') {
+        return [];
+    }
+    return f.geometry.coordinates;
+}
diff --git a/tests/baselines/reference/controlFlowOptionalChain.symbols b/tests/baselines/reference/controlFlowOptionalChain.symbols
index 2665a960a568a..cac0899cc8910 100644
--- a/tests/baselines/reference/controlFlowOptionalChain.symbols
+++ b/tests/baselines/reference/controlFlowOptionalChain.symbols
@@ -1039,93 +1039,627 @@ function f14(o: Thing | null) {
     }
 }
 
-function f20(o: Thing | undefined) {
->f20 : Symbol(f20, Decl(controlFlowOptionalChain.ts, 299, 1))
+function f15(o: Thing | undefined, value: number) {
+>f15 : Symbol(f15, Decl(controlFlowOptionalChain.ts, 299, 1))
 >o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
 >Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+>value : Symbol(value, Decl(controlFlowOptionalChain.ts, 301, 34))
 
-    if (typeof o?.foo === "number") {
+    if (o?.foo === value) {
 >o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
 >o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
 >foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>value : Symbol(value, Decl(controlFlowOptionalChain.ts, 301, 34))
 
         o.foo;
 >o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
 >o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
 >foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
     }
-    if (typeof o?.["foo"] === "number") {
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo !== value) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
 >o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>value : Symbol(value, Decl(controlFlowOptionalChain.ts, 301, 34))
 
-        o["foo"];
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo == value) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>value : Symbol(value, Decl(controlFlowOptionalChain.ts, 301, 34))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo != value) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>value : Symbol(value, Decl(controlFlowOptionalChain.ts, 301, 34))
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
 >o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+}
+
+function f16(o: Thing | undefined) {
+>f16 : Symbol(f16, Decl(controlFlowOptionalChain.ts, 326, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    if (o?.foo === undefined) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>undefined : Symbol(undefined)
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo !== undefined) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>undefined : Symbol(undefined)
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo == undefined) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>undefined : Symbol(undefined)
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (o?.foo != undefined) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>undefined : Symbol(undefined)
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 328, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+}
+
+function f20(o: Thing | undefined) {
+>f20 : Symbol(f20, Decl(controlFlowOptionalChain.ts, 353, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    if (typeof o?.foo === "number") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.["foo"] === "number") {
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
+
+        o["foo"];
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
 >"foo" : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
     }
     if (typeof o?.bar() === "number") {
 >o?.bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
 >bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
 
         o.bar;
 >o.bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
 >bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
     }
     if (o?.baz instanceof Error) {
 >o?.baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
 >baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
 >Error : Symbol(Error, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
 
         o.baz;
 >o.baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 301, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 355, 13))
 >baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
     }
 }
 
 function f21(o: Thing | null) {
->f21 : Symbol(f21, Decl(controlFlowOptionalChain.ts, 314, 1))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>f21 : Symbol(f21, Decl(controlFlowOptionalChain.ts, 368, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
 
     if (typeof o?.foo === "number") {
 >o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
 
         o.foo;
 >o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
     }
     if (typeof o?.["foo"] === "number") {
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 
         o["foo"];
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >"foo" : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
     }
     if (typeof o?.bar() === "number") {
 >o?.bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
 
         o.bar;
 >o.bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >bar : Symbol(bar, Decl(controlFlowOptionalChain.ts, 161, 36))
     }
     if (o?.baz instanceof Error) {
 >o?.baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
 >Error : Symbol(Error, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
 
         o.baz;
 >o.baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
->o : Symbol(o, Decl(controlFlowOptionalChain.ts, 316, 13))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 370, 13))
 >baz : Symbol(baz, Decl(controlFlowOptionalChain.ts, 161, 51))
     }
 }
 
+function f22(o: Thing | undefined) {
+>f22 : Symbol(f22, Decl(controlFlowOptionalChain.ts, 383, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    if (typeof o?.foo === "number") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo !== "number") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo == "number") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo != "number") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 385, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+}
+
+function f23(o: Thing | undefined) {
+>f23 : Symbol(f23, Decl(controlFlowOptionalChain.ts, 410, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    if (typeof o?.foo === "undefined") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo !== "undefined") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo == "undefined") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (typeof o?.foo != "undefined") {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    else {
+        o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 412, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+}
+
+declare function assert(x: unknown): asserts x;
+>assert : Symbol(assert, Decl(controlFlowOptionalChain.ts, 437, 1))
+>x : Symbol(x, Decl(controlFlowOptionalChain.ts, 439, 24))
+>x : Symbol(x, Decl(controlFlowOptionalChain.ts, 439, 24))
+
+declare function assertNonNull<T>(x: T): asserts x is NonNullable<T>;
+>assertNonNull : Symbol(assertNonNull, Decl(controlFlowOptionalChain.ts, 439, 47))
+>T : Symbol(T, Decl(controlFlowOptionalChain.ts, 440, 31))
+>x : Symbol(x, Decl(controlFlowOptionalChain.ts, 440, 34))
+>T : Symbol(T, Decl(controlFlowOptionalChain.ts, 440, 31))
+>x : Symbol(x, Decl(controlFlowOptionalChain.ts, 440, 34))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+>T : Symbol(T, Decl(controlFlowOptionalChain.ts, 440, 31))
+
+function f30(o: Thing | undefined) {
+>f30 : Symbol(f30, Decl(controlFlowOptionalChain.ts, 440, 69))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    if (!!true) {
+        assert(o?.foo);
+>assert : Symbol(assert, Decl(controlFlowOptionalChain.ts, 437, 1))
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (!!true) {
+        assert(o?.foo === 42);
+>assert : Symbol(assert, Decl(controlFlowOptionalChain.ts, 437, 1))
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (!!true) {
+        assert(typeof o?.foo === "number");
+>assert : Symbol(assert, Decl(controlFlowOptionalChain.ts, 437, 1))
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+    if (!!true) {
+        assertNonNull(o?.foo);
+>assertNonNull : Symbol(assertNonNull, Decl(controlFlowOptionalChain.ts, 439, 47))
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 442, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+    }
+}
+
+function f40(o: Thing | undefined) {
+>f40 : Symbol(f40, Decl(controlFlowOptionalChain.ts, 459, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    switch (o?.foo) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        case "abc":
+            o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        case 42:
+            o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        case undefined:
+>undefined : Symbol(undefined)
+
+            o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        default:
+            o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 461, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+    }
+}
+
+function f41(o: Thing | undefined) {
+>f41 : Symbol(f41, Decl(controlFlowOptionalChain.ts, 476, 1))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>Thing : Symbol(Thing, Decl(controlFlowOptionalChain.ts, 159, 1))
+
+    switch (typeof o?.foo) {
+>o?.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+        case "string":
+            o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        case "number":
+            o.foo;
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        case "undefined":
+            o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+        default:
+            o.foo;  // Error
+>o.foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+>o : Symbol(o, Decl(controlFlowOptionalChain.ts, 478, 13))
+>foo : Symbol(foo, Decl(controlFlowOptionalChain.ts, 161, 14))
+
+            break;
+    }
+}
+
+// Repros from #34570
+
+type Shape =
+>Shape : Symbol(Shape, Decl(controlFlowOptionalChain.ts, 493, 1))
+
+    | { type: 'rectangle', width: number, height: number }
+>type : Symbol(type, Decl(controlFlowOptionalChain.ts, 498, 7))
+>width : Symbol(width, Decl(controlFlowOptionalChain.ts, 498, 26))
+>height : Symbol(height, Decl(controlFlowOptionalChain.ts, 498, 41))
+
+    | { type: 'circle', radius: number }
+>type : Symbol(type, Decl(controlFlowOptionalChain.ts, 499, 7))
+>radius : Symbol(radius, Decl(controlFlowOptionalChain.ts, 499, 23))
+
+function getArea(shape?: Shape) {
+>getArea : Symbol(getArea, Decl(controlFlowOptionalChain.ts, 499, 40))
+>shape : Symbol(shape, Decl(controlFlowOptionalChain.ts, 501, 17))
+>Shape : Symbol(Shape, Decl(controlFlowOptionalChain.ts, 493, 1))
+
+    switch (shape?.type) {
+>shape?.type : Symbol(type, Decl(controlFlowOptionalChain.ts, 498, 7), Decl(controlFlowOptionalChain.ts, 499, 7))
+>shape : Symbol(shape, Decl(controlFlowOptionalChain.ts, 501, 17))
+>type : Symbol(type, Decl(controlFlowOptionalChain.ts, 498, 7), Decl(controlFlowOptionalChain.ts, 499, 7))
+
+        case 'circle':
+            return Math.PI * shape.radius ** 2
+>Math.PI : Symbol(Math.PI, Decl(lib.es5.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>PI : Symbol(Math.PI, Decl(lib.es5.d.ts, --, --))
+>shape.radius : Symbol(radius, Decl(controlFlowOptionalChain.ts, 499, 23))
+>shape : Symbol(shape, Decl(controlFlowOptionalChain.ts, 501, 17))
+>radius : Symbol(radius, Decl(controlFlowOptionalChain.ts, 499, 23))
+
+        case 'rectangle':
+            return shape.width * shape.height
+>shape.width : Symbol(width, Decl(controlFlowOptionalChain.ts, 498, 26))
+>shape : Symbol(shape, Decl(controlFlowOptionalChain.ts, 501, 17))
+>width : Symbol(width, Decl(controlFlowOptionalChain.ts, 498, 26))
+>shape.height : Symbol(height, Decl(controlFlowOptionalChain.ts, 498, 41))
+>shape : Symbol(shape, Decl(controlFlowOptionalChain.ts, 501, 17))
+>height : Symbol(height, Decl(controlFlowOptionalChain.ts, 498, 41))
+
+        default:
+            return 0
+    }
+}
+
+type Feature = {
+>Feature : Symbol(Feature, Decl(controlFlowOptionalChain.ts, 510, 1))
+
+  id: string;
+>id : Symbol(id, Decl(controlFlowOptionalChain.ts, 512, 16))
+
+  geometry?: {
+>geometry : Symbol(geometry, Decl(controlFlowOptionalChain.ts, 513, 13))
+
+    type: string;
+>type : Symbol(type, Decl(controlFlowOptionalChain.ts, 514, 14))
+
+    coordinates: number[];
+>coordinates : Symbol(coordinates, Decl(controlFlowOptionalChain.ts, 515, 17))
+
+  };
+};
+
+
+function extractCoordinates(f: Feature): number[] {
+>extractCoordinates : Symbol(extractCoordinates, Decl(controlFlowOptionalChain.ts, 518, 2))
+>f : Symbol(f, Decl(controlFlowOptionalChain.ts, 521, 28))
+>Feature : Symbol(Feature, Decl(controlFlowOptionalChain.ts, 510, 1))
+
+    if (f.geometry?.type !== 'test') {
+>f.geometry?.type : Symbol(type, Decl(controlFlowOptionalChain.ts, 514, 14))
+>f.geometry : Symbol(geometry, Decl(controlFlowOptionalChain.ts, 513, 13))
+>f : Symbol(f, Decl(controlFlowOptionalChain.ts, 521, 28))
+>geometry : Symbol(geometry, Decl(controlFlowOptionalChain.ts, 513, 13))
+>type : Symbol(type, Decl(controlFlowOptionalChain.ts, 514, 14))
+
+        return [];
+    }
+    return f.geometry.coordinates;
+>f.geometry.coordinates : Symbol(coordinates, Decl(controlFlowOptionalChain.ts, 515, 17))
+>f.geometry : Symbol(geometry, Decl(controlFlowOptionalChain.ts, 513, 13))
+>f : Symbol(f, Decl(controlFlowOptionalChain.ts, 521, 28))
+>geometry : Symbol(geometry, Decl(controlFlowOptionalChain.ts, 513, 13))
+>coordinates : Symbol(coordinates, Decl(controlFlowOptionalChain.ts, 515, 17))
+}
+
diff --git a/tests/baselines/reference/controlFlowOptionalChain.types b/tests/baselines/reference/controlFlowOptionalChain.types
index ffec7d1525e4e..13dd6cd5fd0b1 100644
--- a/tests/baselines/reference/controlFlowOptionalChain.types
+++ b/tests/baselines/reference/controlFlowOptionalChain.types
@@ -1170,6 +1170,163 @@ function f14(o: Thing | null) {
     }
 }
 
+function f15(o: Thing | undefined, value: number) {
+>f15 : (o: Thing | undefined, value: number) => void
+>o : Thing | undefined
+>value : number
+
+    if (o?.foo === value) {
+>o?.foo === value : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>value : number
+
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : string | number
+>o : Thing | undefined
+>foo : string | number
+    }
+    if (o?.foo !== value) {
+>o?.foo !== value : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>value : number
+
+        o.foo;  // Error
+>o.foo : string | number
+>o : Thing | undefined
+>foo : string | number
+    }
+    else {
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    if (o?.foo == value) {
+>o?.foo == value : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>value : number
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : string | number
+>o : Thing | undefined
+>foo : string | number
+    }
+    if (o?.foo != value) {
+>o?.foo != value : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>value : number
+
+        o.foo;  // Error
+>o.foo : string | number
+>o : Thing | undefined
+>foo : string | number
+    }
+    else {
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+}
+
+function f16(o: Thing | undefined) {
+>f16 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    if (o?.foo === undefined) {
+>o?.foo === undefined : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>undefined : undefined
+
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    else {
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    if (o?.foo !== undefined) {
+>o?.foo !== undefined : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>undefined : undefined
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    if (o?.foo == undefined) {
+>o?.foo == undefined : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>undefined : undefined
+
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    else {
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    if (o?.foo != undefined) {
+>o?.foo != undefined : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>undefined : undefined
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+}
+
 function f20(o: Thing | undefined) {
 >f20 : (o: Thing | undefined) => void
 >o : Thing | undefined
@@ -1287,3 +1444,445 @@ function f21(o: Thing | null) {
     }
 }
 
+function f22(o: Thing | undefined) {
+>f22 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    if (typeof o?.foo === "number") {
+>typeof o?.foo === "number" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"number" : "number"
+
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : string
+>o : Thing | undefined
+>foo : string
+    }
+    if (typeof o?.foo !== "number") {
+>typeof o?.foo !== "number" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"number" : "number"
+
+        o.foo;  // Error
+>o.foo : string
+>o : Thing | undefined
+>foo : string
+    }
+    else {
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    if (typeof o?.foo == "number") {
+>typeof o?.foo == "number" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"number" : "number"
+
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : string
+>o : Thing | undefined
+>foo : string
+    }
+    if (typeof o?.foo != "number") {
+>typeof o?.foo != "number" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"number" : "number"
+
+        o.foo;  // Error
+>o.foo : string
+>o : Thing | undefined
+>foo : string
+    }
+    else {
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+}
+
+function f23(o: Thing | undefined) {
+>f23 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    if (typeof o?.foo === "undefined") {
+>typeof o?.foo === "undefined" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"undefined" : "undefined"
+
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    else {
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    if (typeof o?.foo !== "undefined") {
+>typeof o?.foo !== "undefined" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"undefined" : "undefined"
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    if (typeof o?.foo == "undefined") {
+>typeof o?.foo == "undefined" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"undefined" : "undefined"
+
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+    else {
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    if (typeof o?.foo != "undefined") {
+>typeof o?.foo != "undefined" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"undefined" : "undefined"
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    else {
+        o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+    }
+}
+
+declare function assert(x: unknown): asserts x;
+>assert : (x: unknown) => asserts x
+>x : unknown
+
+declare function assertNonNull<T>(x: T): asserts x is NonNullable<T>;
+>assertNonNull : <T>(x: T) => asserts x is NonNullable<T>
+>x : T
+
+function f30(o: Thing | undefined) {
+>f30 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    if (!!true) {
+>!!true : true
+>!true : false
+>true : true
+
+        assert(o?.foo);
+>assert(o?.foo) : void
+>assert : (x: unknown) => asserts x
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+    if (!!true) {
+>!!true : true
+>!true : false
+>true : true
+
+        assert(o?.foo === 42);
+>assert(o?.foo === 42) : void
+>assert : (x: unknown) => asserts x
+>o?.foo === 42 : boolean
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>42 : 42
+
+        o.foo;
+>o.foo : 42
+>o : Thing
+>foo : 42
+    }
+    if (!!true) {
+>!!true : true
+>!true : false
+>true : true
+
+        assert(typeof o?.foo === "number");
+>assert(typeof o?.foo === "number") : void
+>assert : (x: unknown) => asserts x
+>typeof o?.foo === "number" : boolean
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+>"number" : "number"
+
+        o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+    }
+    if (!!true) {
+>!!true : true
+>!true : false
+>true : true
+
+        assertNonNull(o?.foo);
+>assertNonNull(o?.foo) : void
+>assertNonNull : <T>(x: T) => asserts x is NonNullable<T>
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+
+        o.foo;
+>o.foo : string | number
+>o : Thing
+>foo : string | number
+    }
+}
+
+function f40(o: Thing | undefined) {
+>f40 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    switch (o?.foo) {
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+
+        case "abc":
+>"abc" : "abc"
+
+            o.foo;
+>o.foo : "abc"
+>o : Thing
+>foo : "abc"
+
+            break;
+        case 42:
+>42 : 42
+
+            o.foo;
+>o.foo : 42
+>o : Thing
+>foo : 42
+
+            break;
+        case undefined:
+>undefined : undefined
+
+            o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+
+            break;
+        default:
+            o.foo;  // Error
+>o.foo : string | number
+>o : Thing | undefined
+>foo : string | number
+
+            break;
+    }
+}
+
+function f41(o: Thing | undefined) {
+>f41 : (o: Thing | undefined) => void
+>o : Thing | undefined
+
+    switch (typeof o?.foo) {
+>typeof o?.foo : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>o?.foo : string | number | undefined
+>o : Thing | undefined
+>foo : string | number | undefined
+
+        case "string":
+>"string" : "string"
+
+            o.foo;
+>o.foo : string
+>o : Thing
+>foo : string
+
+            break;
+        case "number":
+>"number" : "number"
+
+            o.foo;
+>o.foo : number
+>o : Thing
+>foo : number
+
+            break;
+        case "undefined":
+>"undefined" : "undefined"
+
+            o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+
+            break;
+        default:
+            o.foo;  // Error
+>o.foo : never
+>o : Thing | undefined
+>foo : never
+
+            break;
+    }
+}
+
+// Repros from #34570
+
+type Shape =
+>Shape : Shape
+
+    | { type: 'rectangle', width: number, height: number }
+>type : "rectangle"
+>width : number
+>height : number
+
+    | { type: 'circle', radius: number }
+>type : "circle"
+>radius : number
+
+function getArea(shape?: Shape) {
+>getArea : (shape?: { type: "rectangle"; width: number; height: number; } | { type: "circle"; radius: number; } | undefined) => number
+>shape : { type: "rectangle"; width: number; height: number; } | { type: "circle"; radius: number; } | undefined
+
+    switch (shape?.type) {
+>shape?.type : "rectangle" | "circle" | undefined
+>shape : { type: "rectangle"; width: number; height: number; } | { type: "circle"; radius: number; } | undefined
+>type : "rectangle" | "circle" | undefined
+
+        case 'circle':
+>'circle' : "circle"
+
+            return Math.PI * shape.radius ** 2
+>Math.PI * shape.radius ** 2 : number
+>Math.PI : number
+>Math : Math
+>PI : number
+>shape.radius ** 2 : number
+>shape.radius : number
+>shape : { type: "circle"; radius: number; }
+>radius : number
+>2 : 2
+
+        case 'rectangle':
+>'rectangle' : "rectangle"
+
+            return shape.width * shape.height
+>shape.width * shape.height : number
+>shape.width : number
+>shape : { type: "rectangle"; width: number; height: number; }
+>width : number
+>shape.height : number
+>shape : { type: "rectangle"; width: number; height: number; }
+>height : number
+
+        default:
+            return 0
+>0 : 0
+    }
+}
+
+type Feature = {
+>Feature : Feature
+
+  id: string;
+>id : string
+
+  geometry?: {
+>geometry : { type: string; coordinates: number[]; } | undefined
+
+    type: string;
+>type : string
+
+    coordinates: number[];
+>coordinates : number[]
+
+  };
+};
+
+
+function extractCoordinates(f: Feature): number[] {
+>extractCoordinates : (f: Feature) => number[]
+>f : Feature
+
+    if (f.geometry?.type !== 'test') {
+>f.geometry?.type !== 'test' : boolean
+>f.geometry?.type : string | undefined
+>f.geometry : { type: string; coordinates: number[]; } | undefined
+>f : Feature
+>geometry : { type: string; coordinates: number[]; } | undefined
+>type : string | undefined
+>'test' : "test"
+
+        return [];
+>[] : never[]
+    }
+    return f.geometry.coordinates;
+>f.geometry.coordinates : number[]
+>f.geometry : { type: string; coordinates: number[]; }
+>f : Feature
+>geometry : { type: string; coordinates: number[]; }
+>coordinates : number[]
+}
+
diff --git a/tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts b/tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts
index f54275f309c34..49ebd3807db7f 100644
--- a/tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts
+++ b/tests/cases/conformance/controlFlow/controlFlowOptionalChain.ts
@@ -302,6 +302,60 @@ function f14(o: Thing | null) {
     }
 }
 
+function f15(o: Thing | undefined, value: number) {
+    if (o?.foo === value) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo !== value) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo == value) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo != value) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+}
+
+function f16(o: Thing | undefined) {
+    if (o?.foo === undefined) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo !== undefined) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (o?.foo == undefined) {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (o?.foo != undefined) {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+}
+
 function f20(o: Thing | undefined) {
     if (typeof o?.foo === "number") {
         o.foo;
@@ -331,3 +385,146 @@ function f21(o: Thing | null) {
         o.baz;
     }
 }
+
+function f22(o: Thing | undefined) {
+    if (typeof o?.foo === "number") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo !== "number") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo == "number") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo != "number") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+}
+
+function f23(o: Thing | undefined) {
+    if (typeof o?.foo === "undefined") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo !== "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+    if (typeof o?.foo == "undefined") {
+        o.foo;  // Error
+    }
+    else {
+        o.foo;
+    }
+    if (typeof o?.foo != "undefined") {
+        o.foo;
+    }
+    else {
+        o.foo;  // Error
+    }
+}
+
+declare function assert(x: unknown): asserts x;
+declare function assertNonNull<T>(x: T): asserts x is NonNullable<T>;
+
+function f30(o: Thing | undefined) {
+    if (!!true) {
+        assert(o?.foo);
+        o.foo;
+    }
+    if (!!true) {
+        assert(o?.foo === 42);
+        o.foo;
+    }
+    if (!!true) {
+        assert(typeof o?.foo === "number");
+        o.foo;
+    }
+    if (!!true) {
+        assertNonNull(o?.foo);
+        o.foo;
+    }
+}
+
+function f40(o: Thing | undefined) {
+    switch (o?.foo) {
+        case "abc":
+            o.foo;
+            break;
+        case 42:
+            o.foo;
+            break;
+        case undefined:
+            o.foo;  // Error
+            break;
+        default:
+            o.foo;  // Error
+            break;
+    }
+}
+
+function f41(o: Thing | undefined) {
+    switch (typeof o?.foo) {
+        case "string":
+            o.foo;
+            break;
+        case "number":
+            o.foo;
+            break;
+        case "undefined":
+            o.foo;  // Error
+            break;
+        default:
+            o.foo;  // Error
+            break;
+    }
+}
+
+// Repros from #34570
+
+type Shape =
+    | { type: 'rectangle', width: number, height: number }
+    | { type: 'circle', radius: number }
+
+function getArea(shape?: Shape) {
+    switch (shape?.type) {
+        case 'circle':
+            return Math.PI * shape.radius ** 2
+        case 'rectangle':
+            return shape.width * shape.height
+        default:
+            return 0
+    }
+}
+
+type Feature = {
+  id: string;
+  geometry?: {
+    type: string;
+    coordinates: number[];
+  };
+};
+
+
+function extractCoordinates(f: Feature): number[] {
+    if (f.geometry?.type !== 'test') {
+        return [];
+    }
+    return f.geometry.coordinates;
+}