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-rw-r--r--vendor/github.com/onsi/gomega/gexec/prefixed_writer.go53
1 files changed, 53 insertions, 0 deletions
diff --git a/vendor/github.com/onsi/gomega/gexec/prefixed_writer.go b/vendor/github.com/onsi/gomega/gexec/prefixed_writer.go
new file mode 100644
index 0000000..05e695a
--- /dev/null
+++ b/vendor/github.com/onsi/gomega/gexec/prefixed_writer.go
@@ -0,0 +1,53 @@
+package gexec
+
+import (
+ "io"
+ "sync"
+)
+
+/*
+PrefixedWriter wraps an io.Writer, emiting the passed in prefix at the beginning of each new line.
+This can be useful when running multiple gexec.Sessions concurrently - you can prefix the log output of each
+session by passing in a PrefixedWriter:
+
+gexec.Start(cmd, NewPrefixedWriter("[my-cmd] ", GinkgoWriter), NewPrefixedWriter("[my-cmd] ", GinkgoWriter))
+*/
+type PrefixedWriter struct {
+ prefix []byte
+ writer io.Writer
+ lock *sync.Mutex
+ atStartOfLine bool
+}
+
+func NewPrefixedWriter(prefix string, writer io.Writer) *PrefixedWriter {
+ return &PrefixedWriter{
+ prefix: []byte(prefix),
+ writer: writer,
+ lock: &sync.Mutex{},
+ atStartOfLine: true,
+ }
+}
+
+func (w *PrefixedWriter) Write(b []byte) (int, error) {
+ w.lock.Lock()
+ defer w.lock.Unlock()
+
+ toWrite := []byte{}
+
+ for _, c := range b {
+ if w.atStartOfLine {
+ toWrite = append(toWrite, w.prefix...)
+ }
+
+ toWrite = append(toWrite, c)
+
+ w.atStartOfLine = c == '\n'
+ }
+
+ _, err := w.writer.Write(toWrite)
+ if err != nil {
+ return 0, err
+ }
+
+ return len(b), nil
+}