// license that can be found in the LICENSE file.

package types2

import (
	"fmt"
	"go/version"
	"internal/goversion"
)

// A goVersion is a Go language version string of the form "go1.%d"
// where d is the minor version number. goVersion strings don't
// contain release numbers ("go1.20.1" is not a valid goVersion).
type goVersion string

// derived & expanded from cmd/compile/internal/types2/testdata/fixedbugs/issue44688.go2

package main

type A1[T any] struct {
	val T
}

func (p *A1[T]) m1(val T) {
	p.val = val
}

type A2[T any] interface {
	m2(T)
}

type B1[T any] struct {
	filler int
	*A1[T]
	A2[T]
}

type B2[T any] interface {
	A2[T]
}

type ImpA2[T any] struct {
	f T
}

	return t.Underlying()
}

// If t is not a type parameter, coreType returns the underlying type.
// If t is a type parameter, coreType returns the single underlying
// type of all types in its type set if it exists, or nil otherwise. If the
// type set contains only unrestricted and restricted channel types (with
// identical element types), the single underlying type is the restricted
// channel type if the restrictions are always the same, or nil otherwise.

			})
		}
	})
}

func mustInstantiate(tb testing.TB, orig Type, targs ...Type) Type {
	inst, err := Instantiate(nil, orig, targs, true)
	if err != nil {
		tb.Fatal(err)
	}
	return inst
}

// Test that types do not expand infinitely, as in go.dev/issue/52715.
func TestFiniteTypeExpansion(t *testing.T) {
	const src = `
package p

type Tree[T any] struct {
	*Node[T]
}

// Source: ../../cmd/compile/internal/types2/package.go

// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package types

import (
	"fmt"
)

// A Package describes a Go package.
type Package struct {
	path      string
	name      string
	scope     *Scope

}

// Implements reports whether type V implements interface T.
//
// The behavior of Implements is unspecified if V is Typ[Invalid] or an uninstantiated
// generic type.
func Implements(V Type, T *Interface) bool {
	if T.Empty() {
		// All types (even Typ[Invalid]) implement the empty interface.
		return true
	}
	// Checker.implements suppresses errors for invalid types, so we need special
	// handling here.

// This file implements isTerminating.

package types2

import (
	"cmd/compile/internal/syntax"
)

// isTerminating reports if s is a terminating statement.
// If s is labeled, label is the label name; otherwise s
// is "".
func (check *Checker) isTerminating(s syntax.Stmt, label string) bool {
	switch s := s.(type) {
	default:
		panic("unreachable")

		}
	}

	return nil
}

// update de-duplicates n against previously seen types with the hash h.  If an
// identical type is found with the type hash h, the previously seen type is
// returned. Otherwise, n is returned, and recorded in the Context for the hash
// h.
func (ctxt *Context) update(h string, orig Type, targs []Type, inst Type) Type {
	assert(inst != nil)

	ctxt.mu.Lock()
	defer ctxt.mu.Unlock()

// Source: ../../cmd/compile/internal/types2/api_predicates.go

// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// This file implements exported type predicates.

package types

// AssertableTo reports whether a value of type V can be asserted to have type T.
//

package types2

import "strings"

// A termlist represents the type set represented by the union
// t1 ∪ y2 ∪ ... tn of the type sets of the terms t1 to tn.
// A termlist is in normal form if all terms are disjoint.
// termlist operations don't require the operands to be in
// normal form.
type termlist []*term

// allTermlist represents the set of all types.
// It is in normal form.