Upgrade react-router from 7.18.0 to 8.0.1 - #522
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- Bump react-router from 7.18.0 to 8.0.1 (requires React 19.2.7+) - Add import.meta transform to Jest babel config (react-router 8 uses import.meta.hot which Jest cannot parse without it) - Consolidate transformIgnorePatterns into single pattern including react-router alongside d3 and has-ansi All 552 test suites pass (2911 tests).
routerCompat.js was a re-export shim from the v5→v6→v7 migration — all 295 imports now use react-router directly. The history package (used by 191 test files for createMemoryHistory) is replaced by a Jest moduleNameMapper shim that delegates to react-router's UNSAFE_createMemoryHistory with v5Compat enabled. No test file changes needed — they still import from 'history' and the mapper redirects to the shim.
react-router 8 re-exports everything from a single module, so separate import lines from 'react-router' trigger ESLint's import-x/no-duplicates rule. Merge them into single imports. Also fix rtlContexts.js to import createMemoryHistory from the local historyShim instead of the removed 'history' package.
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* Upgrade react-router from 7.18.0 to 8.0.1 - Bump react-router from 7.18.0 to 8.0.1 (requires React 19.2.7+) - Add import.meta transform to Jest babel config (react-router 8 uses import.meta.hot which Jest cannot parse without it) - Consolidate transformIgnorePatterns into single pattern including react-router alongside d3 and has-ansi All 552 test suites pass (2911 tests). * Remove routerCompat.js indirection and history devDependency routerCompat.js was a re-export shim from the v5→v6→v7 migration — all 295 imports now use react-router directly. The history package (used by 191 test files for createMemoryHistory) is replaced by a Jest moduleNameMapper shim that delegates to react-router's UNSAFE_createMemoryHistory with v5Compat enabled. No test file changes needed — they still import from 'history' and the mapper redirects to the shim. * Merge duplicate react-router imports and fix history shim react-router 8 re-exports everything from a single module, so separate import lines from 'react-router' trigger ESLint's import-x/no-duplicates rule. Merge them into single imports. Also fix rtlContexts.js to import createMemoryHistory from the local historyShim instead of the removed 'history' package.
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SUMMARY
Upgrade react-router from 7.18.0 to 8.0.1 and clean up two migration-era leftovers.
react-router 8 upgrade
@babel/plugin-syntax-import-metaand a smallimport.meta→({})transform — react-router 8 usesimport.meta.hotinternally, which Jest cannot parse in CJS moded3|has-ansi|react-router) so react-router is Babel-transformed during testsCleanup: remove routerCompat.js
routerCompat.jswas a re-export shim introduced during the v5→v6→v7 migration. All 295 files that imported from it now import directly from'react-router'. The file is deleted.Cleanup: remove
historydevDependencyThe
historypackage was used by 191 test files forcreateMemoryHistory. It is replaced by a JestmoduleNameMappershim (testUtils/historyShim.js) that delegates to react-router's built-inUNSAFE_createMemoryHistorywithv5Compatenabled. Test files continue to importfrom 'history'unchanged — the mapper redirects to the shim at test time.Depends on: PR #521 (React 19 upgrade) — react-router 8.0.1 has a hard peer dependency on React 19.2.7+.
ISSUE TYPE
COMPONENT NAME
ASCENDER VERSION
ADDITIONAL INFORMATION
Test results: All 552 test suites pass (2911 tests, 0 failures).
This completes the React modernization roadmap critical path:
react-dev-utilswas considered for removal but it is deeply wired into the CRA build scripts (webpack config, dev server, build.js, paths.js) — removing it requires rewriting the build toolchain and is deferred to a future PR.