Error map
componentWillMount renamed Warning: componentWillMount has been renamed, and is not recommended for use.
React · layer 1, On your device
Centre: this error. First ring: errors it is linked with (11). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (11)
Warning: Function components cannot be given refs. Attempts to access this ref will fail. Did you mean to use React.forwardRef()?
A ref was passed to a function component that doesn’t forward it.
Warning: findDOMNode is deprecated and will be removed in the next major release.
A component (often an old library like react-transition-group v1, react-draggable) uses findDOMNode, which StrictMode flags and R…
DeprecationWarning: Buffer() is deprecated due to security and usability issues (DEP0005)
Code (yours or a dependency) uses the deprecated new Buffer() constructor.
[vite] hmr invalidate … Could not Fast Refresh. Export is incompatible.
Fast Refresh fell back to a full reload because the file exports non-components alongside components.
TestingLibraryElementError: Unable to find an element with the text: x
getBy* found no matching element in the rendered output.
npm WARN deprecated package@1.2.3: This package is no longer supported.
A dependency (often a transitive one) is deprecated by its author.
npm WARN config global `--global`, `--local` are deprecated. Use `--location=global` instead.
A deprecation warning printed by npm 8.11–8.12 for the --global flag.
Deprecated: Creation of dynamic property Foo::$bar is deprecated
PHP 8.2+ deprecates creating properties that aren’t declared in the class.
Warning: Support for defaultProps will be removed from function components in a future major release.
A function component (often inside a library) uses Component.defaultProps.
DeprecationWarning: The `punycode` module is deprecated (DEP0040)
A dependency imports Node’s built-in punycode module, deprecated since Node 21.
WARN: the attribute `version` is obsolete, it will be ignored
A harmless Compose v2 warning: the top-level version: line in docker-compose.yml is no longer used.
Two steps away (32)
Warning: A component is changing an uncontrolled input to be controlled
An input’s `value` started as `undefined` (uncontrolled) and later became a defined value (controlled), or vice versa.
error: cannot lock ref 'refs/remotes/origin/x': is at … but expected … / unable to update local ref
Git couldn’t update a reference — stale remote-tracking refs, case-only branch name clashes, or a leftover lock file.
warning: ignoring broken ref refs/remotes/origin/HEAD
A ref file is empty or points to a missing object — usually refs/remotes/origin/HEAD after the default branch changed.
Authentication plugin 'caching_sha2_password' cannot be loaded
An old MySQL client/driver can’t use MySQL 8’s default authentication plugin.
Warning: ReactDOM.render is no longer supported in React 18. Use createRoot instead.
The app uses the legacy root API, so React 18 features (concurrent rendering, automatic batching) are disabled.
no matches for kind "Ingress" in version "extensions/v1beta1" (resource mapping not found)
The manifest uses an apiVersion/kind the cluster doesn’t serve — a removed beta API, or a CRD that isn’t installed.
Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
An Express/Node handler tried to send a second response (or set headers) after one was already sent.
TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json"
An ES module imported a .json file without the required import attribute.
Error: Unhandled 'error' event (events.js / node:events)
An EventEmitter (stream, socket, child process, server) emitted 'error' and nothing listened for it, so Node crashed.
Adjacent JSX elements must be wrapped in an enclosing tag. Did you want a JSX fragment <>...</>?
A component returns two sibling JSX elements without a single parent.
Warning: Cannot update a component (`Parent`) while rendering a different component (`Child`)
A child component updated a parent’s state during its render instead of in an effect or event handler.
[vite] Internal server error: Failed to resolve import "x" from "src/App.jsx". Does the file exist?
Vite couldn’t find an imported file or package.
Warning: An update to Component inside a test was not wrapped in act(...)
A component updated state after the test’s synchronous assertions — async work wasn’t awaited.
Jest: SyntaxError: Cannot use import statement outside a module (Jest encountered an unexpected token)
Jest tried to run untransformed ES module syntax — usually from a dependency in node_modules.
npm ERR! code ERESOLVE — unable to resolve dependency tree
npm 7+ found conflicting peer dependency requirements and refuses to install a broken tree.
npm ERR! code E404 — 404 Not Found: package@version is not in this registry
npm asked the registry for a package (or version) that doesn’t exist there — a typo, a private/scoped package without auth, or th…
npm ERR! code ETARGET — No matching version found for package@^9.9.9
The version range in package.json doesn’t match any published version of the package.
npm WARN old lockfile — The package-lock.json file was created with an old version of npm, so supplemental metadata must be fetched
The lockfile is lockfileVersion 1 (npm 6) and npm 7+ is upgrading it.
npm ERR! cb() never called!
An old npm crash during install — usually network/cache corruption.
Error: Cannot find matching keyid (Corepack signature verification)
An older Corepack couldn’t verify the signature of a newly published pnpm/yarn release after npm rotated its signing keys.
Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated
PHP 8.1+ warns when null is passed to a built-in function that expects a string/int.
Fatal error: Uncaught TypeError: Unsupported operand types: string + int
An arithmetic or array operator was used with incompatible types (PHP 8 is stricter than PHP 7).
Deprecated: Implicit conversion from float 2.5 to int loses precision
PHP 8.1+ warns when a float with a fractional part is silently converted to int (array keys, % operator, int parameters).
/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found
The binary was built on a newer Linux than the one you run it on, and needs a newer glibc than your system has.
Windows upgrade error 0xC1900101 (driver error, rolled back)
A Windows feature update failed and rolled back because a driver crashed or was incompatible during installation.
Minimum supported Gradle version is 8.7. Current version is 8.2
The Android Gradle Plugin (AGP) version in your build needs a newer Gradle wrapper version.
Error: Cannot find module 'x' (MODULE_NOT_FOUND)
Node can’t resolve the module path — the package isn’t installed, or a relative path/extension is wrong.
Gradle: Could not resolve all files for configuration / Could not resolve dependency
Gradle couldn’t download a dependency — wrong coordinates/version, missing repository, offline mode, or network/proxy issues.
java.lang.ClassNotFoundException / NoClassDefFoundError
The JVM couldn’t find a class on the classpath at runtime.
docker compose: services.x Additional property y is not allowed / yaml: line N: mapping values are not allowed
The compose file is invalid YAML or uses a key Compose doesn’t recognise at that level (usually an indentation mistake).
Error response from daemon: network X not found
The container or Compose project refers to a Docker network that doesn’t exist (any more).
Error response from daemon: Pool overlaps with other one on this address space
Docker tried to create a network whose subnet clashes with an existing Docker network (or a VPN/host route).
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