Moves to official vendoring solution

vendor/github.com/onsi/gomega/gbytes/buffer.go

@@ -0,0 +1,229 @@
+/*
+Package gbytes provides a buffer that supports incrementally detecting input.
+
+You use gbytes.Buffer with the gbytes.Say matcher.  When Say finds a match, it fastforwards the buffer's read cursor to the end of that match.
+
+Subsequent matches against the buffer will only operate against data that appears *after* the read cursor.
+
+The read cursor is an opaque implementation detail that you cannot access.  You should use the Say matcher to sift through the buffer.  You can always
+access the entire buffer's contents with Contents().
+
+*/
+package gbytes
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"regexp"
+	"sync"
+	"time"
+)
+
+/*
+gbytes.Buffer implements an io.Writer and can be used with the gbytes.Say matcher.
+
+You should only use a gbytes.Buffer in test code.  It stores all writes in an in-memory buffer - behavior that is inappropriate for production code!
+*/
+type Buffer struct {
+	contents     []byte
+	readCursor   uint64
+	lock         *sync.Mutex
+	detectCloser chan interface{}
+	closed       bool
+}
+
+/*
+NewBuffer returns a new gbytes.Buffer
+*/
+func NewBuffer() *Buffer {
+	return &Buffer{
+		lock: &sync.Mutex{},
+	}
+}
+
+/*
+BufferWithBytes returns a new gbytes.Buffer seeded with the passed in bytes
+*/
+func BufferWithBytes(bytes []byte) *Buffer {
+	return &Buffer{
+		lock:     &sync.Mutex{},
+		contents: bytes,
+	}
+}
+
+/*
+Write implements the io.Writer interface
+*/
+func (b *Buffer) Write(p []byte) (n int, err error) {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	if b.closed {
+		return 0, errors.New("attempt to write to closed buffer")
+	}
+
+	b.contents = append(b.contents, p...)
+	return len(p), nil
+}
+
+/*
+Read implements the io.Reader interface. It advances the
+cursor as it reads.
+
+Returns an error if called after Close.
+*/
+func (b *Buffer) Read(d []byte) (int, error) {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	if b.closed {
+		return 0, errors.New("attempt to read from closed buffer")
+	}
+
+	if uint64(len(b.contents)) <= b.readCursor {
+		return 0, io.EOF
+	}
+
+	n := copy(d, b.contents[b.readCursor:])
+	b.readCursor += uint64(n)
+
+	return n, nil
+}
+
+/*
+Close signifies that the buffer will no longer be written to
+*/
+func (b *Buffer) Close() error {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	b.closed = true
+
+	return nil
+}
+
+/*
+Closed returns true if the buffer has been closed
+*/
+func (b *Buffer) Closed() bool {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	return b.closed
+}
+
+/*
+Contents returns all data ever written to the buffer.
+*/
+func (b *Buffer) Contents() []byte {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	contents := make([]byte, len(b.contents))
+	copy(contents, b.contents)
+	return contents
+}
+
+/*
+Detect takes a regular expression and returns a channel.
+
+The channel will receive true the first time data matching the regular expression is written to the buffer.
+The channel is subsequently closed and the buffer's read-cursor is fast-forwarded to just after the matching region.
+
+You typically don't need to use Detect and should use the ghttp.Say matcher instead.  Detect is useful, however, in cases where your code must
+be branch and handle different outputs written to the buffer.
+
+For example, consider a buffer hooked up to the stdout of a client library.  You may (or may not, depending on state outside of your control) need to authenticate the client library.
+
+You could do something like:
+
+select {
+case <-buffer.Detect("You are not logged in"):
+	//log in
+case <-buffer.Detect("Success"):
+	//carry on
+case <-time.After(time.Second):
+	//welp
+}
+buffer.CancelDetects()
+
+You should always call CancelDetects after using Detect.  This will close any channels that have not detected and clean up the goroutines that were spawned to support them.
+
+Finally, you can pass detect a format string followed by variadic arguments.  This will construct the regexp using fmt.Sprintf.
+*/
+func (b *Buffer) Detect(desired string, args ...interface{}) chan bool {
+	formattedRegexp := desired
+	if len(args) > 0 {
+		formattedRegexp = fmt.Sprintf(desired, args...)
+	}
+	re := regexp.MustCompile(formattedRegexp)
+
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	if b.detectCloser == nil {
+		b.detectCloser = make(chan interface{})
+	}
+
+	closer := b.detectCloser
+	response := make(chan bool)
+	go func() {
+		ticker := time.NewTicker(10 * time.Millisecond)
+		defer ticker.Stop()
+		defer close(response)
+		for {
+			select {
+			case <-ticker.C:
+				b.lock.Lock()
+				data, cursor := b.contents[b.readCursor:], b.readCursor
+				loc := re.FindIndex(data)
+				b.lock.Unlock()
+
+				if loc != nil {
+					response <- true
+					b.lock.Lock()
+					newCursorPosition := cursor + uint64(loc[1])
+					if newCursorPosition >= b.readCursor {
+						b.readCursor = newCursorPosition
+					}
+					b.lock.Unlock()
+					return
+				}
+			case <-closer:
+				return
+			}
+		}
+	}()
+
+	return response
+}
+
+/*
+CancelDetects cancels any pending detects and cleans up their goroutines.  You should always call this when you're done with a set of Detect channels.
+*/
+func (b *Buffer) CancelDetects() {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	close(b.detectCloser)
+	b.detectCloser = nil
+}
+
+func (b *Buffer) didSay(re *regexp.Regexp) (bool, []byte) {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+
+	unreadBytes := b.contents[b.readCursor:]
+	copyOfUnreadBytes := make([]byte, len(unreadBytes))
+	copy(copyOfUnreadBytes, unreadBytes)
+
+	loc := re.FindIndex(unreadBytes)
+
+	if loc != nil {
+		b.readCursor += uint64(loc[1])
+		return true, copyOfUnreadBytes
+	} else {
+		return false, copyOfUnreadBytes
+	}
+}