We've been converging the implementations of educational notes and
diagnostic groups, where both provide category information in
diagnostics (e.g., `[#StrictMemorySafety]`) and corresponding
short-form documentation files. The diagnostic group model is more
useful in a few ways:
* It provides warnings-as-errors control for warnings in the group
* It is easier to associate a diagnostic with a group with
GROUPED_ERROR/GROUPED_WARNING than it is to have a separate diagnostic
ID -> mapping.
* It is easier to see our progress on diagnostic-group coverage
* It provides an easy name to use for diagnostic purposes.
Collapse the educational-notes infrastructure into diagnostic groups,
migrating all of the existing educational notes into new groups.
Simplify the code paths that dealt with multiple educational notes to
have a single, possibly-missing "category documentation URL", which is
how we're treating this.
This commit makes a number of adjustments to how the diagnostic verifier handles source buffers and source locations. Specifically:
• Files named by `-verify-additional-file` are read as late as possible so that if some other component of the compiler has already loaded the file, even in some exotic way (e.g. ClangImporter’s source buffer mirroring), it will use the same buffer.
• Expectation source locations now ignore virtual files and other trickery; they are based on the source buffer and physical location in the file.
Hopefully this will make `-verify-additional-file` work better on Windows. As an unintended side effect, it also changes how expectations work in tests that use `#sourceLocation()`.
This enables one to use varying prefixes when checking diagnostics with the
DiagnosticVerifier. So for instance, I can make a test work both with and
without send-non-sendable enabled by adding additional prefixes. As an example:
```swift
// RUN: %target-swift-frontend ... -verify-additional-prefix no-sns-
// RUN: %target-swift-frontend ... -verify-additional-prefix sns-
let x = ... // expected-error {{This is always checked no matter what prefixes I added}}
let y = ... // expected-no-sns-error {{This is only checked if send non sendable is disabled}}
let z = ... // expected-sns-error {{This is only checked if send non sendable is enabled}}
let w = ... // expected-no-sns-error {{This is checked for a specific error when sns is disabled...}}
// expected-sns-error @-1 {{and for a different error when sns is enabled}}
```
rdar://114643840
You can now put `||` between two fix-its to indicate that the test succeeds if either of them is present. This is meant for situations where a fix-it might vary slightly in different subtests or test configurations.
Also fixes a bug in the diagnostic verifier where "expected-whatever" would search beyond the same line for its opening "{{", potentially finding one many lines away and giving a bad diagnostic and poor recovery behavior.
This change adds a frontend flag, -verify-additional-file, which can be used to pass extra files directly to the diagnostic verifier. These files are not otherwise considered to be Swift source files; they are not compiled or even properly parsed.
This feature can be used to verify diagnostics emitted in non-source files, such as in module interfaces or header files.
Request-based incremental dependencies are enabled by default. For the time being, add a flag that will turn them off and switch back to manual dependency tracking.
When enabled at the driver level, the frontends will inherit the flag. For each frontend that recieves this option, all primaries will have their reference dependencies validated.
Enables Chris's auto-apply-fixes mode for -verify: if an expected-*
annotation has the wrong message, or if the expected fix-its are
incorrect, this option will **edit the original file** to update them.
This is a tool for compiler developers only; it doesn't affect
normal diagnostic printing or normal fix-its.
