Function narrowTypeByEquality

test/fixtures/snapshot/typescript.js:70989–71031

(type, operator, value, assumeTrue)

                return removeNullable ? getTypeWithFacts(type, 2097152 /* TypeFacts.NEUndefinedOrNull */) : type;
            }
            function narrowTypeByEquality(type, operator, value, assumeTrue) {
                if (type.flags & 1 /* TypeFlags.Any */) {
                    return type;
                }
                if (operator === 35 /* SyntaxKind.ExclamationEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */) {
                    assumeTrue = !assumeTrue;
                }
                var valueType = getTypeOfExpression(value);
                if (assumeTrue && (type.flags & 2 /* TypeFlags.Unknown */) && (operator === 34 /* SyntaxKind.EqualsEqualsToken */ || operator === 35 /* SyntaxKind.ExclamationEqualsToken */) && (valueType.flags & 65536 /* TypeFlags.Null */)) {
                    return getUnionType([nullType, undefinedType]);
                }
                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                    if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                        return valueType;
                    }
                    if (valueType.flags & 524288 /* TypeFlags.Object */) {
                        return nonPrimitiveType;
                    }
                    return type;
                }
                if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                    if (!strictNullChecks) {
                        return type;
                    }
                    var doubleEquals = operator === 34 /* SyntaxKind.EqualsEqualsToken */ || operator === 35 /* SyntaxKind.ExclamationEqualsToken */;
                    var facts = doubleEquals ?
                        assumeTrue ? 262144 /* TypeFacts.EQUndefinedOrNull */ : 2097152 /* TypeFacts.NEUndefinedOrNull */ :
                        valueType.flags & 65536 /* TypeFlags.Null */ ?
                            assumeTrue ? 131072 /* TypeFacts.EQNull */ : 1048576 /* TypeFacts.NENull */ :
                            assumeTrue ? 65536 /* TypeFacts.EQUndefined */ : 524288 /* TypeFacts.NEUndefined */;
                    return type.flags & 2 /* TypeFlags.Unknown */ && facts & (1048576 /* TypeFacts.NENull */ | 2097152 /* TypeFacts.NEUndefinedOrNull */) ? nonNullUnknownType : getTypeWithFacts(type, facts);
                }
                if (assumeTrue) {
                    var filterFn = operator === 34 /* SyntaxKind.EqualsEqualsToken */ ?
                        function (t) { return areTypesComparable(t, valueType) || isCoercibleUnderDoubleEquals(t, valueType); } :
                        function (t) { return areTypesComparable(t, valueType); };
                    return replacePrimitivesWithLiterals(filterType(type, filterFn), valueType);
                }
                if (isUnitType(valueType)) {
                    return filterType(type, function (t) { return !(isUnitLikeType(t) && areTypesComparable(t, valueType)); });
                }
                return type;
            }
            function narrowTypeByTypeof(type, typeOfExpr, operator, literal, assumeTrue) {
                // We have '==', '!=', '===', or !==' operator with 'typeof xxx' and string literal operands
                if (operator === 35 /* SyntaxKind.ExclamationEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */) {