gotosocial/vendor/codeberg.org/gruf/go-mangler/load.go
kim b93087ceb4
[chore] update go-structr and go-mangler to no longer rely on modern-go/reflect2 ()
* updates go-structr and go-mangler to no longer rely on modern-go/reflect2 (*phew* now we're go1.23 safe)

* update go-structr version

* bump go-structr to improve memory usage (v. slightly) in certain conditions
2024-06-21 16:43:17 +01:00

224 lines
4.5 KiB
Go

package mangler
import (
"reflect"
)
// loadMangler is the top-most Mangler load function. It guarantees that a Mangler
// function will be returned for given value interface{} and reflected type. Else panics.
func loadMangler(t reflect.Type) Mangler {
ctx := typecontext{rtype: t}
// Load mangler fn
mng := load(ctx)
if mng != nil {
return mng
}
// No mangler function could be determined
panic("cannot mangle type: " + t.String())
}
// load will load a Mangler or reflect Mangler for given type and iface 'a'.
// Note: allocates new interface value if nil provided, i.e. if coming via reflection.
func load(ctx typecontext) Mangler {
if ctx.rtype == nil {
// There is no reflect type to search by
panic("cannot mangle nil interface{} type")
}
// Search by reflection.
mng := loadReflect(ctx)
if mng != nil {
return mng
}
return nil
}
// loadReflect will load a Mangler (or rMangler) function for the given reflected type info.
// NOTE: this is used as the top level load function for nested reflective searches.
func loadReflect(ctx typecontext) Mangler {
switch ctx.rtype.Kind() {
case reflect.Pointer:
return loadReflectPtr(ctx)
case reflect.String:
return mangle_string
case reflect.Struct:
return loadReflectStruct(ctx)
case reflect.Array:
return loadReflectArray(ctx)
case reflect.Slice:
return loadReflectSlice(ctx)
case reflect.Bool:
return mangle_bool
case reflect.Int,
reflect.Uint,
reflect.Uintptr:
return mangle_int
case reflect.Int8, reflect.Uint8:
return mangle_8bit
case reflect.Int16, reflect.Uint16:
return mangle_16bit
case reflect.Int32, reflect.Uint32:
return mangle_32bit
case reflect.Int64, reflect.Uint64:
return mangle_64bit
case reflect.Float32:
return mangle_32bit
case reflect.Float64:
return mangle_64bit
case reflect.Complex64:
return mangle_64bit
case reflect.Complex128:
return mangle_128bit
default:
return nil
}
}
// loadReflectPtr loads a Mangler (or rMangler) function for a ptr's element type.
// This also handles further dereferencing of any further ptr indrections (e.g. ***int).
func loadReflectPtr(ctx typecontext) Mangler {
var n uint
// Iteratively dereference ptrs
for ctx.rtype.Kind() == reflect.Pointer {
ctx.rtype = ctx.rtype.Elem()
n++
}
// Search for elemn type mangler.
if mng := load(ctx); mng != nil {
return deref_ptr_mangler(ctx, mng, n)
}
return nil
}
// loadReflectKnownSlice loads a Mangler function for a
// known slice-of-element type (in this case, primtives).
func loadReflectKnownSlice(ctx typecontext) Mangler {
switch ctx.rtype.Kind() {
case reflect.String:
return mangle_string_slice
case reflect.Bool:
return mangle_bool_slice
case reflect.Int,
reflect.Uint,
reflect.Uintptr:
return mangle_int_slice
case reflect.Int8, reflect.Uint8:
return mangle_8bit_slice
case reflect.Int16, reflect.Uint16:
return mangle_16bit_slice
case reflect.Int32, reflect.Uint32:
return mangle_32bit_slice
case reflect.Int64, reflect.Uint64:
return mangle_64bit_slice
case reflect.Float32:
return mangle_32bit_slice
case reflect.Float64:
return mangle_64bit_slice
case reflect.Complex64:
return mangle_64bit_slice
case reflect.Complex128:
return mangle_128bit_slice
default:
return nil
}
}
// loadReflectSlice ...
func loadReflectSlice(ctx typecontext) Mangler {
// Set nesting type.
ctx.ntype = ctx.rtype
// Get nested element type.
ctx.rtype = ctx.rtype.Elem()
// Preferably look for known slice mangler func
if mng := loadReflectKnownSlice(ctx); mng != nil {
return mng
}
// Use nested mangler iteration.
if mng := load(ctx); mng != nil {
return iter_slice_mangler(ctx, mng)
}
return nil
}
// loadReflectArray ...
func loadReflectArray(ctx typecontext) Mangler {
// Set nesting type.
ctx.ntype = ctx.rtype
// Get nested element type.
ctx.rtype = ctx.rtype.Elem()
// Use manglers for nested iteration.
if mng := load(ctx); mng != nil {
return iter_array_mangler(ctx, mng)
}
return nil
}
// loadReflectStruct ...
func loadReflectStruct(ctx typecontext) Mangler {
var mngs []Mangler
// Set nesting type.
ctx.ntype = ctx.rtype
// Gather manglers for all fields.
for i := 0; i < ctx.ntype.NumField(); i++ {
// Field typectx.
ctx := typecontext{
ntype: ctx.ntype,
rtype: ctx.ntype.Field(i).Type,
}
// Load mangler.
mng := load(ctx)
if mng == nil {
return nil
}
// Append next to map.
mngs = append(mngs, mng)
}
// Use manglers for nested iteration.
return iter_struct_mangler(ctx, mngs)
}