Sources under `packages/flutter_tools/` aren't accessible to the average
Flutter user by navigating through sources from their projects, so it
doesn't need to be as explicitly verbose with types for readability
purposes. The `always_specify_types` lint results in extremely verbose
code within the tool which adds little value.
This change disables `always_specify_types` in favor of a new set of
lints that aim to reduce verbosity by removing obvious types while also
maintaining readability in cases where variable types otherwise wouldn't
be obvious:
- `omit_obvious_local_variable_types`
- `omit_obvious_property_types`
- `specify_nonobvious_local_variable_types`
- `specify_nonobvious_property_types`
This auto-formats all *.dart files in the repository outside of the
`engine` subdirectory and enforces that these files stay formatted with
a presubmit check.
**Reviewers:** Please carefully review all the commits except for the
one titled "formatted". The "formatted" commit was auto-generated by
running `dev/tools/format.sh -a -f`. The other commits were hand-crafted
to prepare the repo for the formatting change. I recommend reviewing the
commits one-by-one via the "Commits" tab and avoiding Github's "Files
changed" tab as it will likely slow down your browser because of the
size of this PR.
---------
Co-authored-by: Kate Lovett <katelovett@google.com>
Co-authored-by: LongCatIsLooong <31859944+LongCatIsLooong@users.noreply.github.com>
This pull request aims to improve code readability, based on feedback gathered in a recent design doc.
<br>
There are two factors that hugely impact how easy it is to understand a piece of code: **verbosity** and **complexity**.
Reducing **verbosity** is important, because boilerplate makes a project more difficult to navigate. It also has a tendency to make one's eyes gloss over, and subtle typos/bugs become more likely to slip through.
Reducing **complexity** makes the code more accessible to more people. This is especially important for open-source projects like Flutter, where the code is read by those who make contributions, as well as others who read through source code as they debug their own projects.
<hr>
<br>
The following examples show how pattern-matching might affect these two factors:
<details> <summary><h3>Example 1 (GOOD)</h3> [click to expand]</summary>
```dart
if (ancestor case InheritedElement(:final InheritedTheme widget)) {
themes.add(widget);
}
```
Without using patterns, this might expand to
```dart
if (ancestor is InheritedElement) {
final InheritedWidget widget = ancestor.widget;
if (widget is InheritedTheme) {
themes.add(widget);
}
}
```
Had `ancestor` been a non-local variable, it would need to be "converted" as well:
```dart
final Element ancestor = this.ancestor;
if (ancestor is InheritedElement) {
final InheritedWidget inheritedWidget = ancestor.widget;
if (widget is InheritedTheme) {
themes.add(theme);
}
}
```
</details>
<details> <summary><h3>Example 2 (BAD) </h3> [click to expand]</summary>
```dart
if (widget case PreferredSizeWidget(preferredSize: Size(:final double height))) {
return height;
}
```
Assuming `widget` is a non-local variable, this would expand to:
```dart
final Widget widget = this.widget;
if (widget is PreferredSizeWidget) {
return widget.preferredSize.height;
}
```
<br>
</details>
In both of the examples above, an `if-case` statement simultaneously verifies that an object meets the specified criteria and performs a variable assignment accordingly.
But there are some differences: Example 2 uses a more deeply-nested pattern than Example 1 but makes fewer useful checks.
**Example 1:**
- checks that `ancestor` is an `InheritedElement`
- checks that the inherited element's `widget` is an `InheritedTheme`
**Example 2:**
- checks that `widget` is a `PreferredSizeWidget`
(every `PreferredSizeWidget` has a `size` field, and every `Size` has a `height` field)
<br>
<hr>
I feel hesitant to try presenting a set of cut-and-dry rules as to which scenarios should/shouldn't use pattern-matching, since there are an abundance of different types of patterns, and an abundance of different places where they might be used.
But hopefully the conversations we've had recently will help us converge toward a common intuition of how pattern-matching can best be utilized for improved readability.
<br><br>
- resolves https://github.com/flutter/flutter/issues/152313
- Design Doc: [flutter.dev/go/dart-patterns](https://flutter.dev/go/dart-patterns)
So there appears to be a race situation between the flutter CLI and Xcode. In the CLI, we update the `CONFIGURATION_BUILD_DIR` in the Xcode build settings and then tell Xcode to install, launch, and debug the app. When Xcode installs the app, it should use the `CONFIGURATION_BUILD_DIR` to find the bundle. However, it appears that sometimes Xcode hasn't processed the change to the build settings before the install happens, which causes it to not be able to find the bundle.
Fixes https://github.com/flutter/flutter/issues/135442
---
Since it's a timing issue, there's not really a consistent way to test it.
I was able to confirm that it works, though, by using the following steps:
1. Create a flutter project
2. Open the project in Xcode
3. `flutter clean`
4. `flutter run --profile -v`
If I saw a print line `stderr: CONFIGURATION_BUILD_DIR: build/Debug-iphoneos`, that means it first found the old and incorrect `CONFIGURATION_BUILD_DIR` before updating to the the new, so I was able to confirm that it would wait until it updated.
Fixes a couple of issues introduced in new iOS 17 physical device tooling: https://github.com/flutter/flutter/pull/131865.
1) Duplicate messages were being filtered out too aggressively.
For example, if on the counter app, you printed "Increment!" on button click, it would only print once no matter how many times you clicked.
Sometimes more than one log source is used at a time and the original intention was to filter duplicates between two log sources, so it wouldn't print the same message from both logs. However, it would also filter when the same message was added more than once via the same log.
The new solution distinguishes a "primary" and a "fallback" log source and prefers to use the primary source unless it's not working, in which it'll use the fallback. If the fallback is faster than the primary, the primary will exclude the logs received by the fallback in a 1-to-1 fashion to prevent too-aggressive filtering. Once a flutter-message has been received by the primary source, fallback messages will be ignored.
Note: iOS < 17 did not regress.
2) There was a race condition between the shutdown hooks and exiting XcodeDebug that was causing a crash when deleting a file that doesn't exist. This only affects CI - for the new integration tests and when testing with iOS 17 physical devices.
This PR includes the following changes. These changes only apply to iOS 17 physical devices.
| Command | Change Description | Changes to User Experience |
| ------------- | ------------- | ------------- |
| `flutter run --release` | Uses `devicectl` to install and launch application in release mode. | No change. |
| `flutter run` | Uses Xcode via automation scripting to run application in debug and profile mode. | Xcode will be opened in the background. Errors/crashes may be caught in Xcode and therefore may not show in terminal. |
| `flutter run --use-application-binary=xxxx` | Creates temporary empty Xcode project and use Xcode to run via automation scripting in debug and profile. | Xcode will be opened in the background. Errors/crashes may be caught in Xcode and therefore may not show in terminal. |
| `flutter install` | Uses `devicectl` to check installed apps, install app, uninstall app. | No change. |
| `flutter screenshot` | Will return error. | Will return error. |
Other changes include:
* Using `devicectl` to get information about the device
* Using `idevicesyslog` and Dart VM logging for device logs
Note:
Xcode automation scripting (used in `flutter run` for debug and profile) does not work in a headless (without a UI) interface. No known workaround.
Fixes https://github.com/flutter/flutter/issues/128827, https://github.com/flutter/flutter/issues/128531.
