grep 'go 1.22.3' go.mod
! grep toolchain go.mod

go get toolchain@1.22.1
stderr '^go: downgraded go 1.22.3 => 1.22.1$'
! stderr toolchain # already gone, was not added
grep 'go 1.22.1' go.mod
! grep toolchain go.mod

env TESTGO_VERSION=go1.22.1
env GOTOOLCHAIN=local
! go get go@1.22.3
stderr 'go: updating go.mod requires go >= 1.22.3 \(running go 1.22.1; GOTOOLCHAIN=local\)$'

env TESTGO_VERSION=go1.30
go get toolchain@1.22.3

func _() {
	// An "invalid array index" compiler error signifies that the constant values have changed.
	// Re-run the stringer command to generate them again.
	var x [1]struct{}
	_ = x[PKCS1WithSHA256-1025]
	_ = x[PKCS1WithSHA384-1281]
	_ = x[PKCS1WithSHA512-1537]
	_ = x[PSSWithSHA256-2052]
	_ = x[PSSWithSHA384-2053]
	_ = x[PSSWithSHA512-2054]
	_ = x[ECDSAWithP256AndSHA256-1027]
	_ = x[ECDSAWithP384AndSHA384-1283]
	_ = x[ECDSAWithP521AndSHA512-1539]

stderr '^go: cannot load module m1_22_1 listed in go.work file: m1_22_1'${/}'go.mod requires go >= 1.22.1 \(running go 1.21; GOTOOLCHAIN=local\)$'
env GOTOOLCHAIN=auto
go work sync
stderr '^go: m1_22_1'${/}'go.mod requires go >= 1.22.1; switching to go1.22.9$'
grep '^go 1.22.1$' go.work
grep '^toolchain go1.22.9$' go.work

# work sync with newer modules should update go 1.22.1 -> 1.24rc1 and drop toolchain

# Create basic modules and work space.
env TESTGO_VERSION=go1.50
mkdir m1_22_0
go mod init -C m1_22_0
go mod edit -C m1_22_0 -go=1.22.0 -toolchain=go1.99.0
mkdir m1_22_1
go mod init -C m1_22_1
go mod edit -C m1_22_1 -go=1.22.1 -toolchain=go1.99.1
mkdir m1_24_rc0
go mod init -C m1_24_rc0
go mod edit -C m1_24_rc0 -go=1.24rc0 -toolchain=go1.99.2

go work init
grep '^go 1.50$' go.work
! grep toolchain go.work

stderr '^go: added toolchain go1.22.9$'

# go get go@1.22.1 should use 1.22.1 exactly, not a later release.
env GOTOOLCHAIN=local
cp go.mod.new go.mod
! go get go@1.22.1
stderr '^go: updating go.mod requires go >= 1.22.1 \(running go 1.21; GOTOOLCHAIN=local\)'

env GOTOOLCHAIN=auto
cp go.mod.new go.mod
go get go@1.22.1
stderr '^go: updating go.mod requires go >= 1.22.1; switching to go1.22.9$'
stderr '^go: upgraded go 1.1 => 1.22.1$'

// between 0 (no coverage) and 10 (max coverage).
func rgb(n int) string {
	if n == 0 {
		return "rgb(192, 0, 0)" // Red
	}
	// Gradient from gray to green.
	r := 128 - 12*(n-1)
	g := 128 + 12*(n-1)
	b := 128 + 3*(n-1)
	return fmt.Sprintf("rgb(%v, %v, %v)", r, g, b)
}

// colors generates the CSS rules for coverage colors.
func colors() template.CSS {
	var buf strings.Builder

cp go.mod.orig go.mod
go get go@1.22
stderr '^go: upgraded go 1.21 => 1.22.9$'
grep 'go 1.22.9' go.mod
grep 'toolchain go1.99rc1' go.mod

# go get go@patch should use the latest patch release
go get go@1.22.1
go get go@patch
stderr '^go: upgraded go 1.22.1 => 1.22.9$'
grep 'go 1.22.9' go.mod
grep 'toolchain go1.99rc1' go.mod

# go get go@1.24 does NOT find the release candidate
cp go.mod.orig go.mod
! go get go@1.24

.section .note.GNU-stack,"",@progbits
EOF

cat >umod-arm64.c <<'EOF'
typedef unsigned int u128 __attribute__((mode(TI)));

static u128 div(u128 x, u128 y, u128 *rp) {
	int n = 0;
	while((y>>(128-1)) != 1 && y < x) {
		y<<=1;
		n++;
	}
	u128 q = 0;
	for(;; n--, y>>=1, q<<=1) {
		if(x>=y) {
			x -= y;
			q |= 1;
		}
		if(n == 0)
			break;
	}
	if(rp)
		*rp = x;
	return q;

stderr 'go mod tidy'

go mod tidy
cat go.mod
go list -f '{{.Module.GoVersion}}'
stdout 1.22

# Adding a@v1.0.01 should upgrade to Go 1.23rc1.
cp go.mod go.mod1
go get example.com/a@v1.0.1
stderr '^go: upgraded go 1.22 => 1.23rc1\ngo: upgraded example.com/a v1.0.0 => v1.0.1\ngo: upgraded example.com/b v1.0.0 => v1.0.1$'
go list -f '{{.Module.GoVersion}}'
stdout 1.23rc1

# Repeating the update with go@1.24.0 should use that Go version.

    assertThat(SignedBytes.join(",", (byte) 1, (byte) 2)).isEqualTo("1,2");
    assertThat(SignedBytes.join("", (byte) 1, (byte) 2, (byte) 3)).isEqualTo("123");
    assertThat(SignedBytes.join(",", (byte) -128, (byte) -1)).isEqualTo("-128,-1");
  }

  @J2ktIncompatible // b/285319375
  public void testLexicographicalComparator() {
    List<byte[]> ordered =
        Arrays.asList(
            new byte[] {},
            new byte[] {LEAST},