Add some instructions for testing changes with the simulator

docs/easy-testing.md

@@ -0,0 +1,96 @@
+# Testing changes with AnkiDroid on an X86_64 sim (Linux)
+
+## Setup
+
+Make sure you can build AnkiDroid first.
+
+Install NDK:
+
+- Download https://developer.android.com/studio#command-tools
+- Rename cmdline-tools to $ANDROID_SDK_ROOT/cmdline-tools/latest
+- Get ndk version from rslib/build.grade
+- .github/scripts/install_ndk.sh 22.0.7026061
+
+Install Rust:
+
+- rustup install 1.54.0
+- rustup target add x86_64-linux-android
+- sudo ln -sf /usr/bin/gcc /usr/bin/x86_64--unknown-linux-gnu-gcc
+
+Install protobuf:
+
+- Install protobuf with your package manager
+- pip install protobuf, or see the venv section below
+
+## Limit build to x86_64
+
+So you don't need to install cross compilers, patch the sources to
+only build the x86_64 image for the aar file:
+
+```diff
+diff --git a/rsdroid/build.gradle b/rsdroid/build.gradle
+index bc3a401..7c69a5b 100644
+--- a/rsdroid/build.gradle
++++ b/rsdroid/build.gradle
+@@ -72,7 +72,7 @@ dependencies {
+
+ }
+
+-preBuild.dependsOn "cargoBuild"
++preBuild.dependsOn "cargoBuildX86_64"
+
+ signing {
+     def hasPrivate = project.hasProperty('SIGNING_PRIVATE_KEY')
+```
+
+## Using a custom python venv
+
+To use a Python venv instead of the system-wide one:
+
+```diff
+diff --git a/tools/protoc-gen/protoc-gen.sh b/tools/protoc-gen/protoc-gen.sh
+index d4039ec..3ac5d29 100755
+--- a/tools/protoc-gen/protoc-gen.sh
++++ b/tools/protoc-gen/protoc-gen.sh
+@@ -1,2 +1,3 @@
+ #!/bin/bash
+-./tools/protoc-gen/protoc-gen.py
++
++$HOME/Local/python/misc/bin/python3 ./tools/protoc-gen/protoc-gen.py
+```
+
+## Build
+
+```
+export ANDROID_SDK_ROOT=$HOME/Android/Sdk
+export PATH=$HOME/Android/Sdk/cmdline-tools/latest/bin/:$PATH
+./gradlew assembleRelease
+```
+
+## Modify AnkiDroid to use built library
+
+Tell gradle to load the compiled .aar file from disk:
+
+```diff
+diff --git a/AnkiDroid/build.gradle b/AnkiDroid/build.gradle
+index a5fa4d6d2..8007dedf4 100644
+--- a/AnkiDroid/build.gradle
++++ b/AnkiDroid/build.gradle
+@@ -263,10 +263,10 @@ dependencies {
+     implementation 'com.github.CanHub:Android-Image-Cropper:4.2.1'
+
+     // build with ./gradlew rsdroid:assembleRelease
+-    // In my experience, using `files()` currently requires a reindex operation.
+-    // implementation files("C:\\GitHub\\Rust-Test\\rsdroid\\build\\outputs\\aar\\rsdroid-release.aar")
++    // after changing one of the lines below, you must run a gradle sync
++    // implementation "io.github.david-allison-1:anki-android-backend:$ankidroid_backend_version"
++    implementation files("../../Anki-Android-Backend/rsdroid/build/outputs/aar/rsdroid-release.aar")
+     implementation 'com.google.protobuf:protobuf-java:3.21.1' // This is required when loading from a file
+-    implementation "io.github.david-allison-1:anki-android-backend:$ankidroid_backend_version"
+     // build with ./gradlew rsdroid-testing:assembleRelease
+     // RobolectricTest.java: replace RustBackendLoader.init(); with RustBackendLoader.loadRsdroid(path);
+     // A path for a testing library is typically under rsdroid-testing/assets
+```
+
+After making the change, force a gradle sync, and then you should be able to build
+and run the project on an x86_64 emulator.