Commit Graph
160 Commits
Author SHA1 Message Date
Tim NeutkensandGitHub a9dc73cfd4 Handle info, group, and groupCollapsed in Strict Mode logging (#25172)
* Handle info, group, and groupCollapsed in Strict Mode logging

While working on the new Next.js router which heavily relies on useReducer I noticed that `group` and `groupCollapsed` which both take labels were showing as-is in the console for the second render/dispatch in Strict Mode logs. While looking at the code I found that `info` was also not instrumented.

I've added additional handling for:
- `info`
- `group`
- `groupCollapsed`

* Remove console.log

* Fix tests
2022-09-06 10:03:27 -07:00
Tianyu YaoandGitHub 181525338e [DevTools] Highlight RN elements on hover (#25106)
* [DevTools] Highlight RN elements on hover

* Remove unused TODO
2022-08-24 11:25:22 -07:00
Tianyu YaoandGitHub 26ba5fb2e0 [DevTools] Add events necessary for click to inspect on RN (#25111)
* Add inspectingNative events for RN

* Enable inspection toggle UI for RN

* Add a stopInspectingNative method for agent
2022-08-19 16:18:14 -07:00
Sebastian SilbermannandGitHub b66936ece7 devtools: Remove ForwardRef/Memo from display name if displayName is set (#21952)
* feat(devtools): Remove ForwardRef/Memo from display name if `displayName` is set

* Avoid potentially wasting work by inlining `functionName`
2022-07-25 09:02:12 +02:00
Luna RuanandGitHub c3b18571db [DevTools][Bugfix] Fix DevTools Perf Issue When Unmounting Large React Subtrees (#24863)
We've recently had multiple reports where, if React DevTools was installed, unmounting large React subtrees would take a huge performance hit (ex. from 50ms to 7 seconds). 

Digging in more, we realized for every fiber that unmounts, we called `untrackFibers`, which calls `clearTimeout` (and does some work manipulating a set, but this wasn't the bulk of the time). We ten call `recordUnmount`, which adds the timer back. Adding and removing the timer so many times was taking upwards of 50ms per timer add/remove call, which was resulting in exorbitant amounts of time spent in DevTools deleting subtrees.

It looks like we are calling `untrackFibers` so many times to avoid a race condition with Suspense children where we unmount them twice (first a "virtual" unmount when the suspense boundary is toggled from visible to invisible, and then an actual unmount when the new children are rendered) without modifying `fiberIDMap`. We can fix this race condition by using the `untrackFibersSet` as a lock and not calling `recordUnmount` if the fiber is in the set and hasn't been processed yet. This works because the only way fibers are added in the set is via `recordUnmount` anyway.

This PR also adds a test to make sure this change doesn't regress the previous behavior.

**Before**
![image](https://user-images.githubusercontent.com/2735514/177655428-774ee306-0568-49ce-987e-b5213b613265.png)

**After**
![image](https://user-images.githubusercontent.com/2735514/177655604-a217583f-787e-438e-b6f9-18953fe32444.png)
2022-07-07 10:43:25 -04:00
Luna RuanandGitHub 955cad9bcc [DevTools] Clean Up DevTools Code (#24782)
This PR cleans up the DevTools codebase by:
* Consolidating `normalizeCodeLocInfo` into one place
* Remove unused source argument in the DevTools component stacks code
2022-06-23 15:47:47 -07:00
9abe745aa7 [DevTools][Timeline Profiler] Component Stacks Backend (#24776)
This PR adds a component stack field to the `schedule-state-update` event. The algorithm is as follows:
* During profiling, whenever a state update happens collect the parents of the fiber that caused the state update and store it in a map
* After profiling finishes, post process the `schedule-state-update` event and using the parent fibers, generate the component stack by using`describeFiber`, a function that uses error throwing to get the location of the component by calling the component without props.

---

Co-authored-by: Blake Friedman <blake.friedman@gmail.com>
2022-06-23 11:19:23 -07:00
Mengdi ChenandGitHub 3e92eb0fce [DevTools] find best renderer when inspecting (#24665)
* [DevTools] find best renderer when inspecting

* fix lint

* fix test

* fix lint

* move logic to agent

* fix lint

* style improvements per review comments

* fix lint & flow

* re-add try catch for safety
2022-06-08 16:01:06 -04:00
Luna RuanandGitHub 0ecb77d4c5 [DevTools] Fix formatWithStyles not styling the results if the first argument is an object + Added unit tests (#24554)
formatWithStyles currently doesn't style the array argument if the first argument is an object. This PR fixes this and also adds unit tests.
2022-05-13 15:34:33 -07:00
Mengdi "Monday" ChenandGitHub 852f10b5cf fix a bug in console.log with non-string args (#24546) 2022-05-12 10:29:36 -04:00
Luna RuanandGitHub d20c3af9d1 [DevTools][Bug] Fix Race Condition When Unmounting Fibers (#24510)
When we delete fibers, we will call onCommitFiberUnmount on every deleted fiber to also remove them from the element tree. However, there are some cases where fibers aren't deleted but we still want to remove them from the element tree (ex. offscreen). In the second case, we recursively remove these children during handleCommitFiberRoot.

When we remove an element, we will untrack its corresponding fiber ID. However, because of fast refresh, we don't do this immediately, opting to instead add the value to a set to process later. However, before the set has been processed, we unmount that fiber again, we will get duplicate unmounts.

To fix this, handleCommitFiberRoot explicitly flushes all the fibers in the set before starting the deletion process. We also need to do this in handleCommitFiberUnmount in case handleCommitFiberRoot gets called first.
2022-05-06 15:36:03 -04:00
Mengdi "Monday" ChenandGitHub e531a4a62d [React DevTools] Improve DevTools UI when Inspecting a user Component that Throws an Error (#24248)
* [ReactDevTools] custom view for errors occur in user's code

* [ReactDevTools] show message for unsupported feature

* fix bad import

* fix typo

* fix issues from rebasing

* prettier

* sync error names

* sync error name with upstream

* fix lint & better comment

* fix error message for test

* better error message per review

* add missing file

* remove dead enum & provide component name in error message

* better error message

* better user facing error message
2022-05-05 20:17:23 -04:00
Luna RuanandGitHub 3dc9a8af05 fix forward ref (#24494)
Resolves #24428

---

For fiber types that render user code, we check the PerformedWork flag rather than the props, ref, and state to see if the fiber rendered (rather than bailing out/etc.) so we know whether we need to do things like record profile durations. ForwardRef wasn't added to this list, which caused #24428.
2022-05-04 13:25:27 -07:00
Luna RuanandGitHub c7e494b553 [React DevTools] Fix regex for formateWithStyles function (#24486)
The previous regex to detect string substitutions is not quite right, this PR fixes it by:

Check to make sure we are starting either at the beginning of the line or we match a character that's not % to make sure we capture all the % in a row.
Make sure there are an odd number of % (the first X pairs are escaped % characters. The odd % followed by a letter is the string substitution)
2022-05-03 15:52:56 -07:00
Billy JanitschandGitHub 726ba80298 Synchronize implementations of second render logging (#24381)
Minor followup to #24373. The fix for #24373 (comment) didn't get synchronized to the hook implementation.
2022-04-15 10:35:35 -05:00
d63cd97245 don't stringify objects for console log second render (#24373)
Fixes #24302 based on #24306.
---

The current implementation for strict mode double logging stringiness and dims the second log. However, because we stringify everything, including objects, this causes objects to be logged as `[object Object]` etc.

This PR creates a new function that formats console log arguments with a specified style. It does this by:
1. The first param is a string that contains %c: Bail out and return the args without modifying the styles. We don't want to affect styles that the developer deliberately set.
2. The first param is a string that doesn't contain %c but contains string formatting: `[`%c${args[0]}`, style, ...args.slice(1)]` Note: we assume that the string formatting that the developer uses is correct.
3. The first param is a string that doesn't contain string formatting OR is not a string: Create a formatting string where:
   -  boolean, string, symbol -> %s
   -  number -> %f OR %i depending on if it's an int or float
   -  default -> %o
---
Co-authored-by: Billy Janitsch <billy@kensho.com>
2022-04-14 11:30:04 -05:00
Brian VaughnandGitHub eaa493e532 Profiler should only report stateful hooks that change between renders (#24189)
The Profiler has an advanced feature that shows why a component re-rendered. In the case of props and (class) state, it shows the names of props/state values that changed between renders. For hooks, DevTools tries to detect which ones may been related to the update by comparing prev/next internal hook structures.

My initial implementation tried to detect all changed hooks. In hindsight this is confusing, because only stateful hooks (e.g. useState, useReducer, and useSyncExternalStore) can schedule an update. (Other types of hooks can change between renders, but in a reactive way.) This PR changes the behavior to only report hooks that scheduled the update.
2022-03-29 11:11:31 -04:00
Andrew ClarkandGitHub 2e0d86d221 Allow updating dehydrated root at lower priority without forcing client render (#24082)
* Pass children to hydration root constructor

I already made this change for the concurrent root API in #23309. This
does the same thing for the legacy API.

Doesn't change any behavior, but I will use this in the next steps.

* Add isRootDehydrated function

Currently this does nothing except read a boolean field, but I'm about
to change this logic.

Since this is accessed by React DOM, too, I put the function in a
separate module that can be deep imported. Previously, it was accessing
the FiberRoot directly. The reason it's a separate module is to break a
circular dependency between React DOM and the reconciler.

* Allow updates at lower pri without forcing client render

Currently, if a root is updated before the shell has finished hydrating
(for example, due to a top-level navigation), we immediately revert to
client rendering. This is rare because the root is expected is finish
quickly, but not exceedingly rare because the root may be suspended.

This adds support for updating the root without forcing a client render
as long as the update has lower priority than the initial hydration,
i.e. if the update is wrapped in startTransition.

To implement this, I had to do some refactoring. The main idea here is
to make it closer to how we implement hydration in Suspense boundaries:

- I moved isDehydrated from the shared FiberRoot object to the
HostRoot's state object.
- In the begin phase, I check if the root has received an by comparing
the new children to the initial children. If they are different, we
revert to client rendering, and set isDehydrated to false using a
derived state update (a la getDerivedStateFromProps).
- There are a few places where we used to set root.isDehydrated to false
as a way to force a client render. Instead, I set the ForceClientRender
flag on the root work-in-progress fiber.
- Whenever we fall back to client rendering, I log a recoverable error.

The overall code structure is almost identical to the corresponding
logic for Suspense components.

The reason this works is because if the update has lower priority than
the initial hydration, it won't be processed during the hydration
render, so the children will be the same.

We can go even further and allow updates at _higher_ priority (though
not sync) by implementing selective hydration at the root, like we do
for Suspense boundaries: interrupt the current render, attempt hydration
at slightly higher priority than the update, then continue rendering the
update. I haven't implemented this yet, but I've structured the code in
anticipation of adding this later.

* Wrap useMutableSource logic in feature flag
2022-03-20 16:18:51 -04:00
Luna RuanandGitHub 645ec5d6fc fix inspecting an element in a nested renderer bug (#24116)
Fixes this issue, where inspecting components in nested renderers results in an error. The reason for this is because we have different fiberToIDMap instances for each renderer, and owners of a component could be in different renderers.

This fix moves the fiberToIDMap and idToArbitraryFiberMap out of the attach method so there's only one instance of each for all renderers.
2022-03-17 15:40:03 -04:00
Brian VaughnandGitHub 48a8574a68 Fixed edge case bug in Profiler (#24031) 2022-03-10 13:35:52 -05:00
salazarmandGitHub d5f1b067c8 [ServerContext] Flight support for ServerContext (#23244)
* Flight side of server context

* 1 more test

* rm unused function

* flow+prettier

* flow again =)

* duplicate ReactServerContext across packages

* store default value when lazily initializing server context

* .

* better comment

* derp... missing import

* rm optional chaining

* missed feature flag

* React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED ??

* add warning if non ServerContext passed into useServerContext

* pass context in as array of arrays

* make importServerContext nott pollute the global context state

* merge main

* remove useServerContext

* dont rely on object getters in ReactServerContext and disallow JSX

* add symbols to devtools + rename globalServerContextRegistry to just ContextRegistry

* gate test case as experimental

* feedback

* remove unions

* Lint

* fix oopsies (tests/lint/mismatching arguments/signatures

* lint again

* replace-fork

* remove extraneous change

* rebase

* 1 more test

* rm unused function

* flow+prettier

* flow again =)

* duplicate ReactServerContext across packages

* store default value when lazily initializing server context

* .

* better comment

* derp... missing import

* rm optional chaining

* missed feature flag

* React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED ??

* add warning if non ServerContext passed into useServerContext

* pass context in as array of arrays

* make importServerContext nott pollute the global context state

* merge main

* remove useServerContext

* dont rely on object getters in ReactServerContext and disallow JSX

* add symbols to devtools + rename globalServerContextRegistry to just ContextRegistry

* gate test case as experimental

* feedback

* remove unions

* Lint

* fix oopsies (tests/lint/mismatching arguments/signatures

* lint again

* replace-fork

* remove extraneous change

* rebase

* reinline

* rebase

* add back changes lost due to rebase being hard

* emit chunk for provider

* remove case for React provider type

* update type for SomeChunk

* enable flag with experimental

* add missing types

* fix flow type

* missing type

* t: any

* revert extraneous type change

* better type

* better type

* feedback

* change import to type import

* test?

* test?

* remove react-dom

* remove react-native-renderer from react-server-native-relay/package.json

* gate change in FiberNewContext, getComponentNameFromType, use switch statement in FlightServer

* getComponentNameFromTpe: server context type gated and use displayName if available

* fallthrough

* lint....

* POP

* lint
2022-03-08 07:55:32 -05:00
Brian VaughnandGitHub 0e0b1a45fa Show DevTools backend and frontend versions in UI (#23399)
This information can help with bug investigation for renderers (like React Native) that embed the DevTools backend into their source (separately from the DevTools frontend, which gets run by the user).

If the DevTools backend is too old to report a version, or if the version reported is the same as the frontend (as will be the case with the browser extension) then only a single version string will be shown, as before. If a different version is reported, then both will be shown separately.
2022-03-02 12:26:48 -05:00
Sebastian MarkbågeandGitHub 1ad8d81292 Remove object-assign polyfill (#23351)
* Remove object-assign polyfill

We really rely on a more modern environment where this is typically
polyfilled anyway and we don't officially support IE with more extensive
polyfilling anyway. So all environments should have the native version
by now.

* Use shared/assign instead of Object.assign in code

This is so that we have one cached local instance in the bundle.

Ideally we should have a compile do this for us but we already follow
this pattern with hasOwnProperty, isArray, Object.is etc.

* Transform Object.assign to now use shared/assign

We need this to use the shared instance when Object.spread is used.
2022-02-23 19:34:24 -05:00
Luna RuanandGitHub 08fce6208e Gracefully handle empty "xstyle" prop values (Part 2) (#23279)
#23190 misses if entry is undefined or null. This fixes this issue.
2022-02-11 14:36:36 -05:00
Luna RuanandGitHub a6987bee73 add <TracingMarker> component boilerplate (#23275)
- Add Tracing Marker component type to React exports
- Add reconciler work tag
- Add devtools work tag
- Add boilerplate for the cache to render children

No functionality yet
2022-02-11 08:42:55 -08:00
Brian VaughnandGitHub fa816be7f0 DevTools: Timeline profiler refactor
Refactor DevTools to record Timeline data (in memory) while profiling. Updated the Profiler UI to import/export Timeline data along with legacy profiler data.

Relates to issue #22529
2022-01-28 13:09:28 -05:00
Brian VaughnandGitHub 934f72221d Gracefully handle empty "xstyle" prop values (#23190) 2022-01-26 13:54:44 -05:00
Brian VaughnandGitHub 13036bfbc8 DevTools should not crawl unmounted subtrees when profiling starts (#23162)
Previously we crawled all subtrees, even not-yet-mounted ones, to initialize context values. This was not only unecessary, but it also caused an error to be thrown. This commit adds a test and fixes that behavior.
2022-01-21 11:05:49 -05:00
Andrew Clark ca143e18d8 Prettier 2022-01-21 09:59:11 -05:00
Behnam MohammadiandGitHub 26baf6a174 styles: replace Array.isArray with module isArray (#23154) 2022-01-21 09:33:00 -05:00
Luna RuanandGitHub 7bee1379b7 Filter out deleted components that are added to the updaters list (#23156)
There was a bug that occurred when a destroy effect is called that causes an update. The update would be added to the updaters list even though the fiber that was calling the destroy effect was unmounted and no longer exists. This PR:

* Adds a patch to Devtools to filter out all in the update list that aren't in the fiberToIDMap (which contains all fibers currently on screen)
2022-01-20 13:29:43 -08:00
Brian VaughnandGitHub d504824780 Enable scheduling profiler flag in react-dom/testing builds (#23142) 2022-01-19 11:20:42 -05:00
Brian VaughnandGitHub 51947a14bb Refactored how React/DevTools log Timeline performance data (#23102)
Until now, DEV and PROFILING builds of React recorded Timeline profiling data using the User Timing API. This commit changes things so that React records this data by calling methods on the DevTools hook. (For now, DevTools still records that data using the User Timing API, to match previous behavior.)

This commit is large but most of it is just moving things around:

* New methods have been added to the DevTools hook (in "backend/profilingHooks") for recording the Timeline performance events.
* Reconciler's "ReactFiberDevToolsHook" has been updated to call these new methods (when they're present).
* User Timing method calls in "SchedulingProfiler" have been moved to DevTools "backend/profilingHooks" (to match previous behavior, for now).
* The old reconciler tests, "SchedulingProfiler-test" and "SchedulingProfilerLabels-test", have been moved into DevTools "TimelineProfiler-test" to ensure behavior didn't change unexpectedly.
* Two new methods have been added to the injected renderer interface: injectProfilingHooks() and getLaneLabelMap().

Relates to #22529.
2022-01-13 14:55:54 -05:00
Brian VaughnandGitHub 911f92a44d DevTools: Support mulitple DevTools instances per page (#22949)
This is being done so that we can embed DevTools within the new React (beta) docs.

The primary changes here are to `react-devtools-inline/backend`:
* Add a new `createBridge` API
* Add an option to the `activate` method to support passing in the custom bridge object.

The `react-devtools-inline` README has been updated to include these new methods.

To verify these changes, this commit also updates the test shell to add a new entry-point for multiple DevTools.

This commit also replaces two direct calls to `window.postMessage()` with `bridge.send()` (and adds the related Flow types).
2021-12-14 12:16:16 -05:00
Brian VaughnandGitHub 3b3daf5573 Advocate for StrictMode usage within Components tree (#22886)
Adds the concept of subtree modes to DevTools to bridge protocol as follows:
1. Add-root messages get two new attributes: one specifying whether the root is running in strict mode and another specifying whether the root (really the root's renderer) supports the concept of strict mode.
2. A new backend message type (TREE_OPERATION_SET_SUBTREE_MODE). This type specifies a subtree root (id) and a mode (bitmask). For now, the only mode this message deals with is strict mode.

The DevTools frontend has been updated as well to highlight non-StrictMode compliant components.

The changes to the bridge protocol require incrementing the bridge protocol version number, which will also require updating the version of react-devtools-core backend that is shipped with React Native.
2021-12-10 11:05:18 -05:00
Brian VaughnandGitHub ad607469c5 StyleX plug-in for resolving atomic styles to values for props.xstyle (#22808)
Adds the concept of "plugins" to the inspected element payload. Also adds the first plugin, one that resolves StyleX atomic style names to their values and displays them as a unified style object (rather than a nested array of objects and booleans).

Source file names are displayed first, in dim color, followed by an ordered set of resolved style values.

For builds with the new feature flag disabled, there is no observable change.

A next step to build on top of this could be to make the style values editable, but change the logic such that editing one directly added an inline style to the item (rather than modifying the stylex class– which may be shared between multiple other components).
2021-12-07 20:04:12 -05:00
Brian VaughnandGitHub 56efc65e58 DevTools should properly report re-renders due to (use)context changes (#22746)
Note that this only fixes things for newer versions of React (e.g. 18 alpha). Older versions will remain broken because there's not a good way to read the most recent context value for a location in the tree after render has completed. This is because React maintains a stack of context values during render, but by the time DevTools is called– render has finished and the stack is empty.
2021-11-11 14:22:22 -05:00
Brian VaughnandGitHub a44a7a2a3f Filter empty commits (all Fibers bailed out) from Profiler (#22745) 2021-11-11 10:35:16 -05:00
Sebastian SilbermannandGitHub ee069065db devtools: Display root type for root updates in "what caused this update?" (#22599) 2021-11-05 11:58:35 -04:00
Konstantin PopovandGitHub 54f6ae9b1c Fix small typos (#22701) 2021-11-04 19:49:06 -04:00
Brian VaughnandGitHub 51c558aeb6 Rename (some) "scheduling profiler" references to "timeline" (#22690) 2021-11-03 15:10:29 -04:00
Andrew ClarkandGitHub 75f3ddebfa Remove experimental useOpaqueIdentifier API (#22672)
useId is the updated version of this API.
2021-11-01 15:02:39 -07:00
Brian VaughnandGitHub 4ba20579da Scheduling Profiler: De-emphasize React internal frames (#22588)
This commit adds code to all React bundles to explicitly register the beginning and ending of the module. This is done by creating Error objects (which capture the file name, line number, and column number) and passing them explicitly to a DevTools hook (when present).

Next, as the Scheduling Profiler logs metadata to the User Timing API, it prints these module ranges along with other metadata (like Lane values and profiler version number).

Lastly, the Scheduling Profiler UI compares stack frames to these ranges when drawing the flame graph and dims or de-emphasizes frames that fall within an internal module.

The net effect of this is that user code (and 3rd party code) stands out clearly in the flame graph while React internal modules are dimmed.

Internal module ranges are completely optional. Older profiling samples, or ones recorded without the React DevTools extension installed, will simply not dim the internal frames.
2021-10-21 14:40:41 -04:00
Konstantin PopovandGitHub f6abf4b400 Fix typos (#22494) 2021-10-20 23:22:41 -04:00
Brian VaughnandGitHub 8ee4ff8836 Surface backend errors during inspection in the frontend UI (#22546) 2021-10-13 10:35:21 -04:00
JuanandGitHub afcb9cdc93 [DevTools] Update Fiber logic in backend renderer to match implementation in React (#22527)
* [DevTools] Update isMountedImpl to match implementation in React

* Also sync findCurrentFiberUsingSlowPathById
2021-10-08 16:19:54 -04:00
Brian VaughnandGitHub 47177247f8 DevTools: Fixed potential cache miss when insepcting elements (#22472) 2021-09-30 12:48:53 -04:00
Brian VaughnandGitHub 2e41568313 DevTools encoding supports multibyte characters (e.g. "🟩") (#22424)
Changes our text encoding approach to properly support multibyte characters following this algorithm. Based on benchmarking, this new approach is roughly equivalent in terms of performance (sometimes slightly faster, sometimes slightly slower).

I also considered using TextEncoder/TextDecoder for this, but it was much slower (~85%).
2021-09-27 13:34:39 -04:00
Justin GrantandGitHub c88fb49d37 Improve DEV errors if string coercion throws (Temporal.*, Symbol, etc.) (#22064)
* Revise ESLint rules for string coercion

Currently, react uses `'' + value` to coerce mixed values to strings.
This code will throw for Temporal objects or symbols.

To make string-coercion safer and to improve user-facing error messages,
This commit adds a new ESLint rule called `safe-string-coercion`.

This rule has two modes: a production mode and a non-production mode.
* If the `isProductionUserAppCode` option is true, then `'' + value`
  coercions are allowed (because they're faster, although they may
  throw) and `String(value)` coercions are disallowed. Exception:
  when building error messages or running DEV-only code in prod
  files, `String()` should be used because it won't throw.
* If the `isProductionUserAppCode` option is false, then `'' + value`
  coercions are disallowed (because they may throw, and in non-prod
  code it's not worth the risk) and `String(value)` are allowed.

Production mode is used for all files which will be bundled with
developers' userland apps. Non-prod mode is used for all other React
code: tests, DEV blocks, devtools extension, etc.

In production mode, in addiiton to flagging `String(value)` calls,
the rule will also flag `'' + value` or `value + ''` coercions that may
throw. The rule is smart enough to silence itself in the following
"will never throw" cases:
* When the coercion is wrapped in a `typeof` test that restricts to safe
  (non-symbol, non-object) types. Example:
    if (typeof value === 'string' || typeof value === 'number') {
      thisWontReport('' + value);
    }
* When what's being coerced is a unary function result, because unary
   functions never return an object or a symbol.
* When the coerced value is a commonly-used numeric identifier:
  `i`, `idx`, or `lineNumber`.
* When the statement immeidately before the coercion is a DEV-only
  call to a function from shared/CheckStringCoercion.js. This call is a
  no-op in production, but in DEV it will show a console error
  explaining the problem, then will throw right after a long explanatory
  code comment so that debugger users will have an idea what's going on.
  The check function call must be in the following format:
    if (__DEV__) {
      checkXxxxxStringCoercion(value);
    };

Manually disabling the rule is usually not necessary because almost all
prod use of the `'' + value` pattern falls into one of the categories
above. But in the rare cases where the rule isn't smart enough to detect
safe usage (e.g. when a coercion is inside a nested ternary operator),
manually disabling the rule will be needed.

The rule should also be manually disabled in prod error handling code
where `String(value)` should be used for coercions, because it'd be
bad to throw while building an error message or stack trace!

The prod and non-prod modes have differentiated error messages to
explain how to do a proper coercion in that mode.

If a production check call is needed but is missing or incorrect
(e.g. not in a DEV block or not immediately before the coercion), then
a context-sensitive error message will be reported so that developers
can figure out what's wrong and how to fix the problem.

Because string coercions are now handled by the `safe-string-coercion`
rule, the `no-primitive-constructor` rule no longer flags `String()`
usage. It still flags `new String(value)` because that usage is almost
always a bug.

* Add DEV-only string coercion check functions

This commit adds DEV-only functions to check whether coercing
values to strings using the `'' + value` pattern will throw. If it will
throw, these functions will:
1. Display a console error with a friendly error message describing
   the problem and the developer can fix it.
2. Perform the coercion, which will throw. Right before the line where
   the throwing happens, there's a long code comment that will help
   debugger users (or others looking at the exception call stack) figure
   out what happened and how to fix the problem.

One of these check functions should be called before all string coercion
of user-provided values, except when the the coercion is guaranteed not
to throw, e.g.
* if inside a typeof check like `if (typeof value === 'string')`
* if coercing the result of a unary function like `+value` or `value++`
* if coercing a variable named in a whitelist of numeric identifiers:
  `i`, `idx`, or `lineNumber`.

The new `safe-string-coercion` internal ESLint rule enforces that
these check functions are called when they are required.

Only use these check functions in production code that will be bundled
with user apps.  For non-prod code (and for production error-handling
code), use `String(value)` instead which may be a little slower but will
never throw.

* Add failing tests for string coercion

Added failing tests to verify:
* That input, select, and textarea elements with value and defaultValue
  set to Temporal-like objects which will throw when coerced to string
  using the `'' + value` pattern.
* That text elements will throw for Temporal-like objects
* That dangerouslySetInnerHTML will *not* throw for Temporal-like
  objects because this value is not cast to a string before passing to
  the DOM.
* That keys that are Temporal-like objects will throw

All tests above validate the friendly error messages thrown.

* Use `String(value)` for coercion in non-prod files

This commit switches non-production code from `'' + value` (which
throws for Temporal objects and symbols) to instead use `String(value)`
which won't throw for these or other future plus-phobic types.

"Non-produciton code" includes anything not bundled into user apps:
* Tests and test utilities. Note that I didn't change legacy React
  test fixtures because I assumed it was good for those files to
  act just like old React, including coercion behavior.
* Build scripts
* Dev tools package - In addition to switching to `String`, I also
  removed special-case code for coercing symbols which is now
  unnecessary.

* Add DEV-only string coercion checks to prod files

This commit adds DEV-only function calls to to check if string coercion
using `'' + value` will throw, which it will if the value is a Temporal
object or a symbol because those types can't be added with `+`.

If it will throw, then in DEV these checks will show a console error
to help the user undertsand what went wrong and how to fix the
problem. After emitting the console error, the check functions will
retry the coercion which will throw with a call stack that's easy (or
at least easier!) to troubleshoot because the exception happens right
after a long comment explaining the issue. So whether the user is in
a debugger, looking at the browser console, or viewing the in-browser
DEV call stack, it should be easy to understand and fix the problem.

In most cases, the safe-string-coercion ESLint rule is smart enough to
detect when a coercion is safe. But in rare cases (e.g. when a coercion
is inside a ternary) this rule will have to be manually disabled.

This commit also switches error-handling code to use `String(value)`
for coercion, because it's bad to crash when you're trying to build
an error message or a call stack!  Because `String()` is usually
disallowed by the `safe-string-coercion` ESLint rule in production
code, the rule must be disabled when `String()` is used.
2021-09-27 10:05:07 -07:00
Behnam MohammadiandGitHub c9d64e5f4c add hasOwnProperty to devTools backend (#22437) 2021-09-27 08:56:56 -04:00