if err := syscall.Exec(os.Args[0], argv, os.Environ()); err != nil {
			t.Fatal(err)
		}
	}

	var cmds []*exec.Cmd
	defer func() {
		for _, cmd := range cmds {
			cmd.Process.Kill()
		}
	}()

	args := append(append([]string(nil), os.Args[1:]...), "-test.run=^Test18146$")
	for n := attempts; n > 0; n-- {
		cmd := exec.Command(os.Args[0], args...)
		cmd.Env = append(os.Environ(), "test18146=exec")

"C", it will look for other non-Go files in the directory and compile
them as part of the Go package. Any .c, .s, .S or .sx files will be
compiled with the C compiler. Any .cc, .cpp, or .cxx files will be
compiled with the C++ compiler. Any .f, .F, .for or .f90 files will be
compiled with the fortran compiler. Any .h, .hh, .hpp, or .hxx files will

			t.Errorf(testname+" (fill 2): m == %d, expected %d", m, len(fus))
		}
		if err != nil {
			t.Errorf(testname+" (fill 3): err should always be nil, found err == %s", err)
		}
		s += fus
		check(t, testname+" (fill 4)", buf, s)
	}
	return s
}

// Fill buf through n writes of byte slice fub.
// The initial contents of buf corresponds to the string s;
// the result is the final contents of buf returned as a string.

		{
			name: "fill error, discard less",
			r: newScriptedReader(func(p []byte) (n int, err error) {
				if len(p) < 5 {
					panic("unexpected small read")
				}
				return 5, errors.New("5-then-error")
			}),
			n:            4,
			want:         4,
			wantErr:      nil,
			wantBuffered: 1,
		},
		{
			name: "fill error, discard equal",

L2::: Use of this source code is governed by a BSD-style
L3::: license that can be found in the LICENSE file.
L4:
L5:@echo off
L6:
L7:setlocal
L8:
L9:if exist make.bat goto ok
L10:echo all.bat must be run from go\src
L11::: cannot exit: would kill parent command interpreter
L12:goto end
L13::ok
L14:
L15:call .\make.bat --no-banner --no-local
L16:if %GOBUILDFAIL%==1 goto end
L17:call .\run.bat --no-rebuild --no-local
L18:if %GOBUILDFAIL%==1 goto end
L19:"%GOTOOLDIR%/dist" banner
L20:
...

limits the impact of these use-after-free bugs by preventing reuse of freed
memory regions until the garbage collector is able to determine that it is
safe. Typically, a use-after-free bug will result in a fault and a helpful
error message, but this package reserves the right to not force a fault on
freed memory. That means a valid implementation of this package is to just

	ast1, err := parser.ParseFile(fset, name, src, flags)
	if err != nil {
		if list, ok := err.(scanner.ErrorList); ok {
			// If err is a scanner.ErrorList, its String will print just
			// the first error and then (+n more errors).
			// Instead, turn it into a new Error that will return
			// details for all the errors.
			for _, e := range list {
				fmt.Fprintln(os.Stderr, e)
			}
			os.Exit(2)
		}

}

var (
	swigOnce sync.Once
	haveSwig bool
)

func mustHaveSwig(t *testing.T) {
	swigOnce.Do(func() {
		mustHaveSwigOnce(t)
		haveSwig = true
	})
	// The first call will skip t with a nice message. On later calls, we just skip.
	if !haveSwig {
		t.Skip("swig not found")
	}
}

func mustHaveSwigOnce(t *testing.T) {
	swig, err := exec.LookPath("swig")
	if err != nil {

index of the first byte of successive UTF-8-encoded code points in the string,
and the second value, of type <code>rune</code>, will be the value of
the corresponding code point.  If the iteration encounters an invalid
UTF-8 sequence, the second value will be <code>0xFFFD</code>,
the Unicode replacement character, and the next iteration will advance
a single byte in the string.
</li>

				NaN,
				0,
				null,
				true,
				false,
				globalThis,
				this,
			];
			this._goRefCounts = new Array(this._values.length).fill(Infinity); // number of references that Go has to a JS value, indexed by reference id
			this._ids = new Map([ // mapping from JS values to reference ids
				[0, 1],
				[null, 2],
				[true, 3],
				[false, 4],