In service of https://github.com/flutter/flutter/issues/143348
This PR makes hot reloads reflect changes to transformer configurations under the `assets` section in pubspec.yaml.
This PR is optimized for ease of implementation, and should not be merged as-is. If it is merged as-is, seriously consider creating a tech debt issue and assigning it to someone to make sure it gets resolved.
This is in service of https://github.com/flutter/flutter/pull/141194
This will make it easier to get the `flutter run -d <browser>` and `flutter build fuschia` cases easier to get under test.
Refactors `ShaderTarget` to make it opaque as to whether it's using Impeller or SkSL and instead has it focus on the target platform it's generating for.
ImpellerC includes SkSL right now whether you ask for it or not.
The tester target also might need SkSL or Vulkan depending on whether `--enable-impeller` is passed.
Part of work on [#101077](https://github.com/flutter/flutter/pull/141194). This is done as a separate PR to avoid a massive diff.
## Context
1. The `FakeCommand` class accepts a list of patterns that's used to match a command given to its `FakeProcessManager`. Since `FakeCommand` can match a list of patterns, not just specifically strings, it can be used to match commands where the exact value of some arguments can't (easily) known ahead of time. For example, a part of the tool may invoke a command with an argument that is the path of a temporarily file that has a randomly-generated basename.
2. The `FakeCommand` class provides on `onRun` parameter, which is a callback that is run when the `FakeProcessManager` runs a command that matches the `FakeCommand` in question.
## Issue
In the event that a `FakeCommand` is constructed using patterns, the test code can't know the exact values used for arguments in the command. This PR proposes changing the type of `onRun` from `VoidCallback?` to `void Function(List<String>)?`. When run, the value `List<String>` parameter will be the full command that the `FakeCommand` matched.
Example:
```dart
FakeCommand(
command: <Pattern>[
artifacts.getArtifactPath(Artifact.engineDartBinary),
'run',
'vector_graphics_compiler',
RegExp(r'--input=/.*\.temp'),
RegExp(r'--output=/.*\.temp'),
],
onRun: (List<String> command) {
final outputPath = (() {
// code to parse `--output` from `command`
})();
testFileSystem.file(outputPath).createSync(recursive: true);
},
)
```
Part of work on https://github.com/flutter/flutter/pull/141194
The [`AssetBundle`](0833929c99/packages/flutter_tools/lib/src/asset.dart (L80)) class contains two members, `entries` and `entryKinds`. `entries` contains asset data indexed by asset key. `entryKinds` contains the "kinds" of these assets, again indexed by asset key.
**Change.** Rather than have two separate maps, this PR proposes combining these maps into one by wrapping the asset data and kind into a single data type `AssetBundleEntry`.
**Purpose.** In https://github.com/flutter/flutter/pull/141194, I am considering associating more information with an asset. In particular, what transformers are meant to be applied to it when copying it to the build output. Rather than adding another map member onto `AssetBundle` (e.g. `entryTransformers`), I decided to make things neater by introducing the `AssetBundleEntry` type.
Fixes https://github.com/flutter/flutter/issues/140665 by replacing use of `setUpAll` and `teardownAll` with `setUp` and `teardown` respectively.
My theory has to how this issue happened (and how this PR fixes it) is that `setUpAll` is not guaranteed to run after any `setUp` in any parent test groups. However, `setUp` is guaranteed to run after any set-up callbacks in parent groups. From the [documentation](https://api.flutter.dev/flutter/flutter_test/setUp.html):
> If this is called within a test group, it applies only to tests in that group. The body will be run after any set-up callbacks in parent groups or at the top level.
Meanwhile, [`setUpAll`](https://api.flutter.dev/flutter/flutter_test/setUpAll.html) has a weaker documented guarantee that applies only to other `setUpAll` calls:
> If this is called within a test group, The body will run before all tests in that group. It will be run after any [setUpAll](https://api.flutter.dev/flutter/flutter_test/setUpAll.html) callbacks in parent groups or at the top level. It won't be run if none of the tests in the group are run.
Reverts flutter/flutter#132985
Initiated by: christopherfujino
This change reverts the following previous change:
Original Description:
Provides support for conditional bundling of assets through the existing `--flavor` option for `flutter build` and `flutter run`. Closes https://github.com/flutter/flutter/issues/21682. Resolves https://github.com/flutter/flutter/issues/136092
## Change
Within the `assets` section pubspec.yaml, the user can now specify one or more `flavors` that an asset belongs to. Consider this example:
```yaml
# pubspec.yaml
flutter:
assets:
- assets/normal-asset.png
- path: assets/vanilla/ice-cream.png
flavors:
- vanilla
- path: assets/strawberry/ice-cream.png
flavors:
- strawberry
```
With this pubspec,
* `flutter run --flavor vanilla` will not include `assets/strawberry/ice-cream.png` in the build output.
* `flutter run --flavor strawberry` will not include `assets/vanilla/ice-cream.png`.
* `flutter run` will only include `assets/normal-asset.png`.
## Open questions
* Should this be supported for all platforms, or should this change be limited to ones with documented `--flavor` support (Android, iOS, and (implicitly) MacOS)? This PR currently only enables this feature for officially supported platforms.
## Design thoughts, what this PR does not do, etc.
### This does not provide an automatic mapping/resolution of asset keys/paths to others based on flavor at runtime.
The implementation in this PR represents a simplest approach. Notably, it does not give Flutter the ability to dynamically choose an asset based on flavor using a single asset key. For example, one can't use `Image.asset('config.json')` to dynamically choose between different "flavors" of `config.json` (such as `dev-flavor/config.json` or `prod-flavor/config.json`). However, a user could always implement such a mechanism in their project or in a library by examining the flavor at runtime.
### When multiple entries affect the same file and 1) at least one of these entries have a `flavors` list provided and 2) these lists are not equivalent, we always consider the manifest to be ambiguous and will throw a `ToolExit`.
<details>
For example, these manifests would all be considered ambiguous:
```yaml
assets:
- assets/
- path: assets/vanilla.png
flavors:
- vanilla
assets:
- path: assets/vanilla/
flavors:
- vanilla
- path: assets/vanilla/cherry.png
flavor:
- cherry
# Thinking towards the future where we might add glob/regex support and more conditions other than flavor:
assets:
- path: assets/vanilla/**
flavors:
- vanilla
- path: assets/**/ios/**
platforms:
- ios
# Ambiguous in the case of assets like "assets/vanilla/ios/icon.svg" since we
# don't know if flavor `vanilla` and platform `ios` should be combined using or-logic or and-logic.
```
See [this review comment thread](https://github.com/flutter/flutter/pull/132985#discussion_r1381909942) for the full story on how I arrived at this decision.
</details>
### This does not support Android's multidimensional flavors feature (in an intuitive way)
<details>
Conder this excerpt from a Flutter project's android/app/build.gradle file:
```groovy
android {
// ...
flavorDimensions "mode", "api"
productFlavors {
free {
dimension "mode"
applicationIdSuffix ".free"
}
premium {
dimension "mode"
applicationIdSuffix ".premium"
}
minApi23 {
dimension "api"
versionNameSuffix "-minApi23"
}
minApi21 {
dimension "api"
versionNameSuffix "-minApi21"
}
}
}
```
In this setup, the following values are valid `--flavor` are valid `freeMinApi21`, `freeMinApi23`, `premiumMinApi21`, and `premiumMinApi23`. We call these values "flavor combinations". Consider the following from the Android documentation[^1]:
> In addition to the source set directories you can create for each individual product flavor and build variant, you can also create source set directories for each combination of product flavors. For example, you can create and add Java sources to the src/demoMinApi24/java/ directory, and Gradle uses those sources only when building a variant that combines those two product flavors.
>
> Source sets you create for product flavor combinations have a higher priority than source sets that belong to each individual product flavor. To learn more about source sets and how Gradle merges resources, read the section about how to [create source sets](https://developer.android.com/build/build-variants#sourcesets).
This feature will not behave in this way. If a user utilizes this feature and also Android's multidimensional flavors feature, they will have to list out all flavor combinations that contain the flavor they want to limit an asset to:
```yaml
assets:
- assets/free/
flavors:
- freeMinApi21
- freeMinApi23
```
This is mostly due to a technical limitation in the hot-reload feature of `flutter run`. During a hot reload, the tool will try to update the asset bundle on the device, but the tool does not know the flavors contained within the flavor combination (that the user passes to `--flavor`). Gradle is the source of truth of what flavors were involved in the build, and `flutter run` currently does not access to that information since it's an implementation detail of the build process. We could bubble up this information, but it would require a nontrivial amount of engineering work, and it's unclear how desired this functionality is. It might not be worth implementing.
</details>
See https://flutter.dev/go/flavor-specific-assets for the (outdated) design document.
<summary>Pre-launch Checklist</summary>
</details>
[^1]: https://developer.android.com/build/build-variants#flavor-dimensions
Provides support for conditional bundling of assets through the existing `--flavor` option for `flutter build` and `flutter run`. Closes https://github.com/flutter/flutter/issues/21682. Resolves https://github.com/flutter/flutter/issues/136092
## Change
Within the `assets` section pubspec.yaml, the user can now specify one or more `flavors` that an asset belongs to. Consider this example:
```yaml
# pubspec.yaml
flutter:
assets:
- assets/normal-asset.png
- path: assets/vanilla/ice-cream.png
flavors:
- vanilla
- path: assets/strawberry/ice-cream.png
flavors:
- strawberry
```
With this pubspec,
* `flutter run --flavor vanilla` will not include `assets/strawberry/ice-cream.png` in the build output.
* `flutter run --flavor strawberry` will not include `assets/vanilla/ice-cream.png`.
* `flutter run` will only include `assets/normal-asset.png`.
## Open questions
* Should this be supported for all platforms, or should this change be limited to ones with documented `--flavor` support (Android, iOS, and (implicitly) MacOS)? This PR currently only enables this feature for officially supported platforms.
## Design thoughts, what this PR does not do, etc.
### This does not provide an automatic mapping/resolution of asset keys/paths to others based on flavor at runtime.
The implementation in this PR represents a simplest approach. Notably, it does not give Flutter the ability to dynamically choose an asset based on flavor using a single asset key. For example, one can't use `Image.asset('config.json')` to dynamically choose between different "flavors" of `config.json` (such as `dev-flavor/config.json` or `prod-flavor/config.json`). However, a user could always implement such a mechanism in their project or in a library by examining the flavor at runtime.
### When multiple entries affect the same file and 1) at least one of these entries have a `flavors` list provided and 2) these lists are not equivalent, we always consider the manifest to be ambiguous and will throw a `ToolExit`.
<details>
For example, these manifests would all be considered ambiguous:
```yaml
assets:
- assets/
- path: assets/vanilla.png
flavors:
- vanilla
assets:
- path: assets/vanilla/
flavors:
- vanilla
- path: assets/vanilla/cherry.png
flavor:
- cherry
# Thinking towards the future where we might add glob/regex support and more conditions other than flavor:
assets:
- path: assets/vanilla/**
flavors:
- vanilla
- path: assets/**/ios/**
platforms:
- ios
# Ambiguous in the case of assets like "assets/vanilla/ios/icon.svg" since we
# don't know if flavor `vanilla` and platform `ios` should be combined using or-logic or and-logic.
```
See [this review comment thread](https://github.com/flutter/flutter/pull/132985#discussion_r1381909942) for the full story on how I arrived at this decision.
</details>
### This does not support Android's multidimensional flavors feature (in an intuitive way)
<details>
Conder this excerpt from a Flutter project's android/app/build.gradle file:
```groovy
android {
// ...
flavorDimensions "mode", "api"
productFlavors {
free {
dimension "mode"
applicationIdSuffix ".free"
}
premium {
dimension "mode"
applicationIdSuffix ".premium"
}
minApi23 {
dimension "api"
versionNameSuffix "-minApi23"
}
minApi21 {
dimension "api"
versionNameSuffix "-minApi21"
}
}
}
```
In this setup, the following values are valid `--flavor` are valid `freeMinApi21`, `freeMinApi23`, `premiumMinApi21`, and `premiumMinApi23`. We call these values "flavor combinations". Consider the following from the Android documentation[^1]:
> In addition to the source set directories you can create for each individual product flavor and build variant, you can also create source set directories for each combination of product flavors. For example, you can create and add Java sources to the src/demoMinApi24/java/ directory, and Gradle uses those sources only when building a variant that combines those two product flavors.
>
> Source sets you create for product flavor combinations have a higher priority than source sets that belong to each individual product flavor. To learn more about source sets and how Gradle merges resources, read the section about how to [create source sets](https://developer.android.com/build/build-variants#sourcesets).
This feature will not behave in this way. If a user utilizes this feature and also Android's multidimensional flavors feature, they will have to list out all flavor combinations that contain the flavor they want to limit an asset to:
```yaml
assets:
- assets/free/
flavors:
- freeMinApi21
- freeMinApi23
```
This is mostly due to a technical limitation in the hot-reload feature of `flutter run`. During a hot reload, the tool will try to update the asset bundle on the device, but the tool does not know the flavors contained within the flavor combination (that the user passes to `--flavor`). Gradle is the source of truth of what flavors were involved in the build, and `flutter run` currently does not access to that information since it's an implementation detail of the build process. We could bubble up this information, but it would require a nontrivial amount of engineering work, and it's unclear how desired this functionality is. It might not be worth implementing.
</details>
See https://flutter.dev/go/flavor-specific-assets for the (outdated) design document.
<summary>Pre-launch Checklist</summary>
</details>
[^1]: https://developer.android.com/build/build-variants#flavor-dimensions
This PR modifies the web build slightly to create an `AssetManifest.json`, that is a JSON(base64)-encoded version of the `AssetManifest.bin` file.
_(This should enable all browsers to download the file without any interference, and all servers to serve it with the correct headers.)_
It also modifies Flutter's `AssetManifest` class so it loads and uses said file `if (kIsWeb)`.
### Issues
* Fixes https://github.com/flutter/flutter/issues/124883
### Tests
* Unit tests added.
* Some tests that run on the Web needed to be informed of the new filename, but their behavior didn't have to change (binary contents are the same across all platforms).
* I've deployed a test app, so users affected by the BIN issue may take a look at the PR in action:
* https://dit-tests.web.app
