0xfffffffd,
		0xfffffffe,
		0xffffffff,
	}
	for _, x := range testCases {
		for _, y := range testCases {
			if got, want := sqDiff(x, y), orig(x, y); got != want {
				t.Fatalf("sqDiff(%#x, %#x): got %d, want %d", x, y, got, want)
			}
		}
	}
	if err := quick.CheckEqual(orig, sqDiff, &quick.Config{MaxCountScale: 10}); err != nil {
		t.Fatal(err)
	}

# 'go list' accepts package paths with pluses.
cp go.mod.orig go.mod
go get example.net/cmd
go list example.net/cmd/x++

# 'go list -m' rejects module paths with pluses.
! go list -versions -m 'example.net/bad++'
stderr '^go: malformed module path "example.net/bad\+\+": invalid char ''\+''$'

# 'go get' accepts package paths with pluses.
cp go.mod.orig go.mod
go get example.net/cmd/x++
go list -m example.net/cmd

	// that case, re-use the existing instance.
	for i, ctxt := range ctxts {
		if inst := ctxt.lookup(hashes[i], orig, targs); inst != nil {
			return updateContexts(inst)
		}
	}

	switch orig := orig.(type) {
	case *Named:
		res = check.newNamedInstance(pos, orig, targs, expanding) // substituted lazily

	case *Alias:
		// TODO(gri) is this correct?

# subcommands when certain kinds of cycles were present
# in the build graph.

env GO111MODULE=on

cp go.mod go.mod.orig
go mod tidy
cmp go.mod go.mod.orig

# If the go.mod file is already tidy, 'go mod graph' should not modify it.
go mod graph
cmp go.mod go.mod.orig

-- go.mod --
module root

go 1.13

replace (
	a v0.1.0 => ./a1
	b v0.1.0 => ./b1
	b v0.2.0 => ./b2
	c v0.1.0 => ./c1

#         |
#         + ------------- requireincompatible v0.1.0 ---- incompatible v2.0.0+incompatible

cp go.mod go.mod.orig
go mod tidy
cmp go.mod go.mod.orig

# Make sure that -diff behaves the same as tidy.
[exec:patch] mv go.mod go.mod.tidyResult
[exec:patch] mv go.sum go.sum.tidyResult
[exec:patch] cp go.mod.orig go.mod
[exec:patch] ! go mod tidy -diff
[exec:patch] cp stdout diff.patch
[exec:patch] exec patch -p1 -i diff.patch

# a lower compatible version when upgrading.
cp go.mod go.mod.orig
go mod tidy
cmp go.mod.orig go.mod
grep '^example.com/incompatiblewithsub v2\.0\.0\+incompatible' go.sum
! grep '^example.com/incompatiblewithsub v1.0.0' go.sum

go get example.com/incompatiblewithsub/sub
cmp go.mod.orig go.mod
! grep '^example.com/incompatiblewithsub v1.0.0' go.sum

		assert(n.loader == nil)     // instances are created by instantiation, in which case n.loader is nil

		orig := n.inst.orig
		orig.resolve()
		underlying := n.expandUnderlying()

		n.tparams = orig.tparams
		n.underlying = underlying
		n.fromRHS = orig.fromRHS // for cycle detection

		if len(orig.methods) == 0 {
			n.setState(complete) // nothing further to do
			n.inst.ctxt = nil
		} else {

		assert(n.loader == nil)     // instances are created by instantiation, in which case n.loader is nil

		orig := n.inst.orig
		orig.resolve()
		underlying := n.expandUnderlying()

		n.tparams = orig.tparams
		n.underlying = underlying
		n.fromRHS = orig.fromRHS // for cycle detection

		if len(orig.methods) == 0 {
			n.setState(complete) // nothing further to do
			n.inst.ctxt = nil
		} else {

    policies:
      ns[foo]-policy[httpbin]-rule[0]:
        permissions:
        - andRules:
            rules:
            - any: true
        principals:
        - andIds:
            ids:
            - orIds:
                ids:
                - authenticated:
                    principalName:
                      exact: spiffe://td1/ns/rule[0]/sa/from[0]-principal[0]
                - authenticated:

cp go.mod go.mod.orig
go mod tidy
cmp go.mod go.mod.orig

-- go.mod --
module m.test

go 1.16
-- .ignore.go --
package p