In this PR, we add a generic views.ValuePointer type that can be used as a view for pointers
to basic types and struct types that do not require deep cloning and do not have corresponding
view types. Its Get/GetOk methods return stack-allocated shallow copies of the underlying value.
We then update the cmd/viewer codegen to produce getters that return either concrete views
when available or ValuePointer views when not, for pointer fields in generated view types.
This allows us to avoid unnecessary allocations compared to returning pointers to newly
allocated shallow copies.
Updates #14570
Signed-off-by: Nick Khyl <nickk@tailscale.com>
We have several checked type assertions to *types.Named in both cmd/cloner and cmd/viewer.
As Go 1.23 updates the go/types package to produce Alias type nodes for type aliases,
these type assertions no longer work as expected unless the new behavior is disabled
with gotypesalias=0.
In this PR, we add codegen.NamedTypeOf(t types.Type), which functions like t.(*types.Named)
but also unrolls type aliases. We then use it in place of type assertions in the cmd/cloner and
cmd/viewer packages where appropriate.
We also update type switches to include *types.Alias alongside *types.Named in relevant cases,
remove *types.Struct cases when switching on types.Type.Underlying and update the tests
with more cases where type aliases can be used.
Updates #13224
Updates #12912
Signed-off-by: Nick Khyl <nickk@tailscale.com>
Go 1.23 updates the go/types package to produce Alias type nodes for type aliases, unless disabled with gotypesalias=0.
This new default behavior breaks codegen.LookupMethod, which uses checked type assertions to types.Named and
types.Interface, as only named types and interfaces have methods.
In this PR, we update codegen.LookupMethod to perform method lookup on the right-hand side of the alias declaration
and clearly switch on the supported type nodes types. We also improve support for various edge cases, such as when an alias
is used as a type parameter constraint, and add tests for the LookupMethod function.
Additionally, we update cmd/viewer/tests to include types with aliases used in type fields and generic type constraints.
Updates #13224
Updates #12912
Signed-off-by: Nick Khyl <nickk@tailscale.com>
This PR modifies viewTypeForContainerType to use the last type parameter of a container type
as the value type, enabling the implementation of map-like container types where the second-to-last
(usually first) type parameter serves as the key type.
It also adds a MapContainer type to test the code generation.
Updates #12736
Signed-off-by: Nick Khyl <nickk@tailscale.com>
This adds support for container-like types such as Container[T] that
don't explicitly specify a view type for T. Instead, a package implementing
a container type should also implement and export a ContainerView[T, V] type
and a ContainerViewOf(*Container[T]) ContainerView[T, V] function, which
returns a view for the specified container, inferring the element view type V
from the element type T.
Updates #12736
Signed-off-by: Nick Khyl <nickk@tailscale.com>
This adds support for generic types and interfaces to our cloner and viewer codegens.
It updates these packages to determine whether to make shallow or deep copies based
on the type parameter constraints. Additionally, if a template parameter or an interface
type has View() and Clone() methods, we'll use them for getters and the cloner of the
owning structure.
Updates #12736
Signed-off-by: Nick Khyl <nickk@tailscale.com>
We had a misstep with the semantics when applying an optimization that
showed up in the roll into corp. This test ensures that case and related
cases must be retained.
Updates #9410
Updates #9601
Signed-off-by: James Tucker <james@tailscale.com>
This reverts commit ee90cd02fd.
The outcome is not identical for empty slices. Cloner really needs
tests!
Updates #9601
Signed-off-by: James Tucker <james@tailscale.com>
tailcfg.Node zero-value clone equality checks failed when I added a
[]*foo to the structure, as the zero value and it's clone contained a
different slice header.
Updates #9377
Updates #9408
Signed-off-by: James Tucker <james@tailscale.com>
I noticed cmd/{cloner,viewer} didn't support structs with embedded
fields while working on a change in another repo. This adds support.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This updates all source files to use a new standard header for copyright
and license declaration. Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.
This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.
Updates #6865
Signed-off-by: Will Norris <will@tailscale.com>
Nick Khyl
James Tucker
Maisem Ali
Brad Fitzpatrick
Will Norris