}
	}
}

// testNonEmptyWriter wraps an io.Writer and ensures that
// Write is never called with an empty buffer.
type testNonEmptyWriter struct{ io.Writer }

func (w testNonEmptyWriter) Write(b []byte) (int, error) {
	if len(b) == 0 {
		return 0, errors.New("unexpected empty Write call")
	}
	return w.Writer.Write(b)
}

func TestFileWriter(t *testing.T) {
	type (

	func C.GoBytes(unsafe.Pointer, C.int) []byte

As a special case, C.malloc does not call the C library malloc directly
but instead calls a Go helper function that wraps the C library malloc
but guarantees never to return nil. If C's malloc indicates out of memory,
the helper function crashes the program, like when Go itself runs out
of memory. Because C.malloc cannot fail, it has no two-result form
that returns errno.

		Context: context,
	})
}

// Save calls to C.xxx for later processing.
func (f *File) saveCall(call *ast.CallExpr, context astContext) {
	sel, ok := call.Fun.(*ast.SelectorExpr)
	if !ok {
		return
	}
	if l, ok := sel.X.(*ast.Ident); !ok || l.Name != "C" {
		return
	}
	c := &Call{Call: call, Deferred: context == ctxDefer}
	f.Calls = append(f.Calls, c)
}

</pre>

<p>
The expression must be a function or method call; it cannot be parenthesized.
Calls of built-in functions are restricted as for
<a href="#Expression_statements">expression statements</a>.
</p>

<p>
Each time a "defer" statement
executes, the function value and parameters to the call are
<a href="#Calls">evaluated as usual</a>
and saved anew but the actual function is not invoked.

func TestEqual(t *testing.T) {
	// Run the tests and check for allocation at the same time.
	allocs := testing.AllocsPerRun(10, func() {
		for _, tt := range compareTests {
			eql := Equal(tt.a, tt.b)
			if eql != (tt.i == 0) {
				t.Errorf(`Equal(%q, %q) = %v`, tt.a, tt.b, eql)
			}
		}
	})
	if allocs > 0 {
		t.Errorf("Equal allocated %v times", allocs)
	}
}

func TestEqualExhaustive(t *testing.T) {
	var size = 128

	0x001d 00029 (x.go:4)	PCDATA	$0, $0
	0x001d 00029 (x.go:4)	PCDATA	$1, $0
	0x001d 00029 (x.go:4)	CALL	runtime.printlock(SB)
	0x0022 00034 (x.go:4)	MOVQ	$3, (SP)
	0x002a 00042 (x.go:4)	CALL	runtime.printint(SB)
	0x002f 00047 (x.go:4)	CALL	runtime.printnl(SB)
	0x0034 00052 (x.go:4)	CALL	runtime.printunlock(SB)
	0x0039 00057 (x.go:5)	MOVQ	8(SP), BP
	0x003e 00062 (x.go:5)	ADDQ	$16, SP
	0x0042 00066 (x.go:5)	RET

	buf := NewReader(r)
	allocs := testing.AllocsPerRun(100, func() {
		r.Seek(0, io.SeekStart)
		buf.Reset(r)

		_, err := buf.ReadString('\n')
		if err != nil {
			t.Fatal(err)
		}
	})
	if allocs != 1 {
		t.Errorf("Unexpected number of allocations, got %f, want 1", allocs)
	}
}

func TestWriter(t *testing.T) {
	var data [8192]byte

			readBytes, _ := buf.Read(tmp)
			yBytes := Repeat(y, growLen)
			allocs := testing.AllocsPerRun(100, func() {
				buf.Grow(growLen)
				buf.Write(yBytes)
			})
			// Check no allocation occurs in write, as long as we're single-threaded.
			if allocs != 0 {
				t.Errorf("allocation occurred during write")
			}
			// Check that buffer has correct data.

		buf.Write(fb)
	}
	buf.Write(frag)
	return buf.String(), err
}

// WriteTo implements io.WriterTo.
// This may make multiple calls to the [Reader.Read] method of the underlying [Reader].
// If the underlying reader supports the [Reader.WriteTo] method,
// this calls the underlying [Reader.WriteTo] without buffering.
func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
	b.lastByte = -1
	b.lastRuneSize = -1

	io.Writer
	fileState

	ReadFrom(io.Reader) (int64, error)
}

// Flush finishes writing the current file's block padding.
// The current file must be fully written before Flush can be called.
//
// This is unnecessary as the next call to [Writer.WriteHeader] or [Writer.Close]
// will implicitly flush out the file's padding.
func (tw *Writer) Flush() error {
	if tw.err != nil {
		return tw.err
	}