This commit reduces the code surface that interacts with raw JSON data,
reducing code complexity and improving maintainability.
Files that needed to be changed drastically were additionally
cleaned up to remove any code cruft that has accrued over time.
In order to facility this the following changes were made:
* Move JSON handling from `CascadiaSettings` into `SettingsLoader`
This allows us to use STL containers for data model instances.
For instance profiles are now added to a hashmap for O(1) lookup.
* JSON parsing within `SettingsLoader` doesn't differentiate between user,
inbox and fragment JSON data, reducing code complexity and size.
It also centralizes common concerns, like profile deduplication and
ensuring that all profiles are assigned a GUID.
* Direct JSON modification, like the insertion of dynamic profiles into
settings.json were removed. This vastly reduces code complexity,
but unfortunately removes support for comments in JSON on first start.
* `ColorScheme`s cannot be layered. As such its `LayerJson` API was replaced
with `FromJson`, allowing us to remove JSON-based color scheme validation.
* `Profile`s used to test their wish to layer using `ShouldBeLayered`, which
was replaced with a GUID-based hashmap lookup on previously parsed profiles.
Further changes were made as improvements upon the previous changes:
* Compact the JSON files embedded binary, saving 28kB
* Prevent double-initialization of the color table in `ColorScheme`
* Making `til::color` getters `constexpr`, allow better optimizations
The result is a reduction of:
* 48kB binary size for the Settings.Model.dll
* 5-10% startup duration
* 26% code for the `CascadiaSettings` class
* 1% overall code in this project
Furthermore this results in the following breaking changes:
* The long deprecated "globals" settings object will not be detected and no
warning will be created during load.
* The initial creation of a new settings.json will not produce helpful comments.
Both cases are caused by the removal of manual JSON handling and the
move to representing the settings file with model objects instead
## PR Checklist
* [x] Closes#5276
* [x] Closes#7421
* [x] I work here
* [x] Tests added/passed
## Validation Steps Performed
* Out-of-box-experience is identical to before ✔️
(Except for the settings.json file lacking comments.)
* Existing user settings load correctly ✔️
* New WSL instances are added to user settings ✔️
* New fragments are added to user settings ✔️
* All profiles are assigned GUIDs ✔️
WriteUTF8FileAtomic overrides the content of the file "atomically"
by creating a temp file and then renaming it to the original path.
The problem arises when the original path is symbolic link,
as the link itself gets overridden by a file (rather than the link target).
This PR introduces a special handling of the symlinks:
if the path as a symlink we resolve the path and use:
1. target's directory to create a temp-file in
2. target itself to be replaced with the tempfile.
Symlink resolution is problematic when the target path does not exist,
as there is no good utility that resolves such link (canonical() fails).
In this corner case we skip the "atomic" approach of renaming the file
and write the link target directly.
Closes#10787
This commit introduces a basic ApplicationState class, without being used for anything yet to aid reviewers. At a later point actual usages of this new class may be added separately.
## References
This commit is an initial step towards implementing #8324.
## PR Checklist
* [x] I work here
* [x] Tests added/passed
## Validation Steps Performed
* Creating a `state.json` with `{"generatedProfiles":["{53e75ed9-2b63-4118-856d-0510c4f6b97e}"]}` updates the ApplicationState, as observed through a debugger ✔️
* Deleting the "generatedProfiles" field sets the corresponding field back to nullopt ✔️
