| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @flow |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * The `'' + value` pattern (used in perf-sensitive code) throws for Symbol |
| 12 | * and Temporal.* types. See https://github.com/facebook/react/pull/22064. |
| 13 | * |
| 14 | * The functions in this module will throw an easier-to-understand, |
| 15 | * easier-to-debug exception with a clear errors message message explaining the |
| 16 | * problem. (Instead of a confusing exception thrown inside the implementation |
| 17 | * of the `value` object). |
| 18 | */ |
| 19 | |
| 20 | // $FlowFixMe[incompatible-type] only called in DEV, so void return is not possible. |
| 21 | function typeName(value: mixed): string { |
| 22 | if (__DEV__) { |
| 23 | // toStringTag is needed for namespaced types like Temporal.Instant |
| 24 | const hasToStringTag = typeof Symbol === 'function' && Symbol.toStringTag; |
| 25 | const type = |
| 26 | (hasToStringTag && (value as any)[Symbol.toStringTag]) || |
| 27 | (value as any).constructor.name || |
| 28 | 'Object'; |
| 29 | // $FlowFixMe[incompatible-type] |
| 30 | return type; |
| 31 | } |
| 32 | } |
| 33 | |
| 34 | // $FlowFixMe[incompatible-type] only called in DEV, so void return is not possible. |
| 35 | function willCoercionThrow(value: mixed): boolean { |
| 36 | if (__DEV__) { |
| 37 | try { |
| 38 | testStringCoercion(value); |
| 39 | return false; |
| 40 | } catch (e) { |
| 41 | return true; |
| 42 | } |
| 43 | } |
| 44 | } |
| 45 | |
| 46 | /** @noinline */ |
| 47 | function testStringCoercion(value: mixed) { |
| 48 | // If you ended up here by following an exception call stack, here's what's |
| 49 | // happened: you supplied an object or symbol value to React (as a prop, key, |
| 50 | // DOM attribute, CSS property, string ref, etc.) and when React tried to |
| 51 | // coerce it to a string using `'' + value`, an exception was thrown. |
| 52 | // |
| 53 | // The most common types that will cause this exception are `Symbol` instances |
| 54 | // and Temporal objects like `Temporal.Instant`. But any object that has a |
| 55 | // `valueOf` or `[Symbol.toPrimitive]` method that throws will also cause this |
| 56 | // exception. (Library authors do this to prevent users from using built-in |
| 57 | // numeric operators like `+` or comparison operators like `>=` because custom |
| 58 | // methods are needed to perform accurate arithmetic or comparison.) |
| 59 | // |
| 60 | // To fix the problem, coerce this object or symbol value to a string before |
| 61 | // passing it to React. The most reliable way is usually `String(value)`. |
| 62 | // |
| 63 | // To find which value is throwing, check the browser or debugger console. |
| 64 | // Before this exception was thrown, there should be `console.error` output |
| 65 | // that shows the type (Symbol, Temporal.PlainDate, etc.) that caused the |
| 66 | // problem and how that type was used: key, atrribute, input value prop, etc. |
| 67 | // In most cases, this console output also shows the component and its |
| 68 | // ancestor components where the exception happened. |
| 69 | // |
| 70 | // eslint-disable-next-line react-internal/safe-string-coercion |
| 71 | return '' + (value as any); |
| 72 | } |
| 73 | |
| 74 | export function checkAttributeStringCoercion( |
| 75 | value: mixed, |
| 76 | attributeName: string, |
| 77 | ): void | string { |
| 78 | if (__DEV__) { |
| 79 | if (willCoercionThrow(value)) { |
| 80 | console.error( |
| 81 | 'The provided `%s` attribute is an unsupported type %s.' + |
| 82 | ' This value must be coerced to a string before using it here.', |
| 83 | attributeName, |
| 84 | typeName(value), |
| 85 | ); |
| 86 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 87 | } |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | export function checkKeyStringCoercion(value: mixed): void | string { |
| 92 | if (__DEV__) { |
| 93 | if (willCoercionThrow(value)) { |
| 94 | console.error( |
| 95 | 'The provided key is an unsupported type %s.' + |
| 96 | ' This value must be coerced to a string before using it here.', |
| 97 | typeName(value), |
| 98 | ); |
| 99 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | export function checkPropStringCoercion( |
| 105 | value: mixed, |
| 106 | propName: string, |
| 107 | ): void | string { |
| 108 | if (__DEV__) { |
| 109 | if (willCoercionThrow(value)) { |
| 110 | console.error( |
| 111 | 'The provided `%s` prop is an unsupported type %s.' + |
| 112 | ' This value must be coerced to a string before using it here.', |
| 113 | propName, |
| 114 | typeName(value), |
| 115 | ); |
| 116 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 117 | } |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | export function checkOptionStringCoercion( |
| 122 | value: mixed, |
| 123 | propName: string, |
| 124 | ): void | string { |
| 125 | if (__DEV__) { |
| 126 | if (willCoercionThrow(value)) { |
| 127 | console.error( |
| 128 | 'The provided `%s` option is an unsupported type %s.' + |
| 129 | ' This value must be coerced to a string before using it here.', |
| 130 | propName, |
| 131 | typeName(value), |
| 132 | ); |
| 133 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 134 | } |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | export function checkCSSPropertyStringCoercion( |
| 139 | value: mixed, |
| 140 | propName: string, |
| 141 | ): void | string { |
| 142 | if (__DEV__) { |
| 143 | if (willCoercionThrow(value)) { |
| 144 | console.error( |
| 145 | 'The provided `%s` CSS property is an unsupported type %s.' + |
| 146 | ' This value must be coerced to a string before using it here.', |
| 147 | propName, |
| 148 | typeName(value), |
| 149 | ); |
| 150 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 151 | } |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | export function checkHtmlStringCoercion(value: mixed): void | string { |
| 156 | if (__DEV__) { |
| 157 | if (willCoercionThrow(value)) { |
| 158 | console.error( |
| 159 | 'The provided HTML markup uses a value of unsupported type %s.' + |
| 160 | ' This value must be coerced to a string before using it here.', |
| 161 | typeName(value), |
| 162 | ); |
| 163 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 164 | } |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | export function checkFormFieldValueStringCoercion(value: mixed): void | string { |
| 169 | if (__DEV__) { |
| 170 | if (willCoercionThrow(value)) { |
| 171 | console.error( |
| 172 | 'Form field values (value, checked, defaultValue, or defaultChecked props)' + |
| 173 | ' must be strings, not %s.' + |
| 174 | ' This value must be coerced to a string before using it here.', |
| 175 | typeName(value), |
| 176 | ); |
| 177 | return testStringCoercion(value); // throw (to help callers find troubleshooting comments) |
| 178 | } |
| 179 | } |
| 180 | } |