docs: clarify the Android Hermes vendoring steps - #411
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The Android setup has two separate requirements — building React Native from source and pointing it at the vendored Hermes — and the doc ran them together without saying why either is needed. - Split them into their own sections and say up front that this is the manual equivalent of what `pod install` does on Apple platforms. - Note that apps based on react-native-test-app get the dependency substitutions from `react.buildFromSource=true` instead of editing settings.gradle themselves, as apps/test-app does. - Spell out that REACT_NATIVE_OVERRIDE_HERMES_DIR is read from the environment (Gradle cannot set it for its own build), so it has to be exported for every shell — or for the environment Android Studio is launched from — and what goes wrong without it. Also drop the last two references to a "patched" Hermes from the host README, left over from before we adopted Hermes' first-party Node-API. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01HX4imsygeawVtsmoP1sj3F
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The Android setup has two separate requirements — building React Native from source and pointing it at the vendored Hermes — and the doc ran them together without saying why either is needed. - Split them into their own sections and say up front that this is the manual equivalent of what `pod install` does on Apple platforms. - Note that apps based on react-native-test-app get the dependency substitutions from `react.buildFromSource=true` instead of editing settings.gradle themselves, as apps/test-app does. - Spell out that REACT_NATIVE_OVERRIDE_HERMES_DIR is read from the environment (Gradle cannot set it for its own build), so it has to be exported for every shell — or for the environment Android Studio is launched from — and what goes wrong without it. Also drop the last two references to a "patched" Hermes from the host README, left over from before we adopted Hermes' first-party Node-API. Claude-Session: https://claude.ai/code/session_01HX4imsygeawVtsmoP1sj3F Co-authored-by: Claude <noreply@anthropic.com>
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docs/ANDROID.mdlisted the two Android requirements — building React Nativefrom source, and pointing that build at the vendored Hermes — as one run-on
section, without saying why either is needed or what happens when the
environment variable isn't set.
equivalent of what the podspec does during
pod installon Apple platforms.react-native-test-appdon't hand-editsettings.gradle: it applies the same dependency substitutions whenreact.buildFromSource=trueis set, which is howapps/test-appin thisrepository builds.
REACT_NATIVE_OVERRIDE_HERMES_DIRis read from theenvironment —
ReactAndroid/hermes-engine/build.gradle.ktsusesSystem.getenv, and Gradle cannot set a variable for its own build — so ithas to be exported for every shell that invokes Gradle, or for the
environment Android Studio is launched from. Without it React Native builds
its own Hermes and the app fails to link
hermes_napi_create_env.Also drops the last two "patched Hermes" references from the host README, left
over from before #372 adopted Hermes' first-party Node-API.
No behavior changes, so no changeset.
Generated by Claude Code