Use generics for providers API

Using generics for the providers API allows a type to be associated
with a ProviderKey, resulting in a type-safe API without that doesn't
require runtime type assertions by every caller.

Unfortunately, Go does not allow generic types in methods, only in
functions [1].  This prevents a type-safe API on ModuleContext, and
requires moving the API to be functions that take a ModuleContext as
a parameter.

This CL creates the new API, but doesn't convert all of the callers.

[1] https://go.googlesource.com/proposal/+/refs/heads/master/design/43651-type-parameters.md#no-parameterized-methods)

Bug: 316410648
Test: builds
Change-Id: I3e30d68b966b730efd968166a38a25cc144bd6de
This commit is contained in:
Colin Cross
2023-12-12 14:13:26 -08:00
parent e8eeec913f
commit 3c0a83d19f
12 changed files with 212 additions and 30 deletions

View File

@@ -79,26 +79,30 @@ type BaseModuleContext interface {
// not set it returns the zero value of the type of the provider, so the return value can always
// be type asserted to the type of the provider. The value returned may be a deep copy of the
// value originally passed to SetProvider.
OtherModuleProvider(m blueprint.Module, provider blueprint.ProviderKey) interface{}
OtherModuleProvider(m blueprint.Module, provider blueprint.AnyProviderKey) any
// OtherModuleHasProvider returns true if the provider for the given module has been set.
OtherModuleHasProvider(m blueprint.Module, provider blueprint.ProviderKey) bool
OtherModuleHasProvider(m blueprint.Module, provider blueprint.AnyProviderKey) bool
otherModuleProvider(m blueprint.Module, provider blueprint.AnyProviderKey) (any, bool)
// Provider returns the value for a provider for the current module. If the value is
// not set it returns the zero value of the type of the provider, so the return value can always
// be type asserted to the type of the provider. It panics if called before the appropriate
// mutator or GenerateBuildActions pass for the provider. The value returned may be a deep
// copy of the value originally passed to SetProvider.
Provider(provider blueprint.ProviderKey) interface{}
Provider(provider blueprint.AnyProviderKey) any
// HasProvider returns true if the provider for the current module has been set.
HasProvider(provider blueprint.ProviderKey) bool
HasProvider(provider blueprint.AnyProviderKey) bool
provider(provider blueprint.AnyProviderKey) (any, bool)
// SetProvider sets the value for a provider for the current module. It panics if not called
// during the appropriate mutator or GenerateBuildActions pass for the provider, if the value
// is not of the appropriate type, or if the value has already been set. The value should not
// be modified after being passed to SetProvider.
SetProvider(provider blueprint.ProviderKey, value interface{})
SetProvider(provider blueprint.AnyProviderKey, value interface{})
GetDirectDepsWithTag(tag blueprint.DependencyTag) []Module
@@ -260,19 +264,35 @@ func (b *baseModuleContext) OtherModuleReverseDependencyVariantExists(name strin
func (b *baseModuleContext) OtherModuleType(m blueprint.Module) string {
return b.bp.OtherModuleType(m)
}
func (b *baseModuleContext) OtherModuleProvider(m blueprint.Module, provider blueprint.ProviderKey) interface{} {
func (b *baseModuleContext) OtherModuleProvider(m blueprint.Module, provider blueprint.AnyProviderKey) any {
value, _ := b.bp.OtherModuleProvider(m, provider)
return value
}
func (b *baseModuleContext) OtherModuleHasProvider(m blueprint.Module, provider blueprint.AnyProviderKey) bool {
_, ok := b.bp.OtherModuleProvider(m, provider)
return ok
}
func (b *baseModuleContext) otherModuleProvider(m blueprint.Module, provider blueprint.AnyProviderKey) (any, bool) {
return b.bp.OtherModuleProvider(m, provider)
}
func (b *baseModuleContext) OtherModuleHasProvider(m blueprint.Module, provider blueprint.ProviderKey) bool {
return b.bp.OtherModuleHasProvider(m, provider)
func (b *baseModuleContext) Provider(provider blueprint.AnyProviderKey) any {
value, _ := b.bp.Provider(provider)
return value
}
func (b *baseModuleContext) Provider(provider blueprint.ProviderKey) interface{} {
func (b *baseModuleContext) HasProvider(provider blueprint.AnyProviderKey) bool {
_, ok := b.bp.Provider(provider)
return ok
}
func (b *baseModuleContext) provider(provider blueprint.AnyProviderKey) (any, bool) {
return b.bp.Provider(provider)
}
func (b *baseModuleContext) HasProvider(provider blueprint.ProviderKey) bool {
return b.bp.HasProvider(provider)
}
func (b *baseModuleContext) SetProvider(provider blueprint.ProviderKey, value interface{}) {
func (b *baseModuleContext) SetProvider(provider blueprint.AnyProviderKey, value any) {
b.bp.SetProvider(provider, value)
}