diff --git a/README.md b/README.md
index 91b829f1dd..fe4b73cd19 100644
--- a/README.md
+++ b/README.md
@@ -152,6 +152,15 @@ This happens when a new import is added. Run `dep ensure` to install the missing
As `dep status` suggests, run `dep ensure` to update your lockfile. Then run `dep status` again, and the lock mismatch should go away.
+### Visualizing dependencies
+
+Generate a visual representation of the dependency tree by piping the output of `dep status -dot` to [graphviz](http://www.graphviz.org/).
+```
+$ brew install graphviz
+$ dep status -dot | dot -T png | open -f -a /Applications/Preview.app
+```
+

+
### Updating dependencies
Updating brings the version of a dependency in `Gopkg.lock` and `vendor/` to the latest version allowed by the constraints in `Gopkg.toml`.
diff --git a/docs/img/StatusGraph.png b/docs/img/StatusGraph.png
new file mode 100644
index 0000000000..ab506ca146
Binary files /dev/null and b/docs/img/StatusGraph.png differ
diff --git a/internal/fs/fs.go b/internal/fs/fs.go
index 84f0346856..90d6f87908 100644
--- a/internal/fs/fs.go
+++ b/internal/fs/fs.go
@@ -318,6 +318,13 @@ func copyFile(src, dst string) (err error) {
return
}
+ // Temporary fix for Go < 1.9
+ //
+ // See: https://github.com/golang/dep/issues/774
+ // and https://github.com/golang/go/issues/20829
+ if runtime.GOOS == "windows" {
+ dst = fixLongPath(dst)
+ }
err = os.Chmod(dst, si.Mode())
return
@@ -400,3 +407,133 @@ func IsSymlink(path string) (bool, error) {
return l.Mode()&os.ModeSymlink == os.ModeSymlink, nil
}
+
+// fixLongPath returns the extended-length (\\?\-prefixed) form of
+// path when needed, in order to avoid the default 260 character file
+// path limit imposed by Windows. If path is not easily converted to
+// the extended-length form (for example, if path is a relative path
+// or contains .. elements), or is short enough, fixLongPath returns
+// path unmodified.
+//
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath
+func fixLongPath(path string) string {
+ // Do nothing (and don't allocate) if the path is "short".
+ // Empirically (at least on the Windows Server 2013 builder),
+ // the kernel is arbitrarily okay with < 248 bytes. That
+ // matches what the docs above say:
+ // "When using an API to create a directory, the specified
+ // path cannot be so long that you cannot append an 8.3 file
+ // name (that is, the directory name cannot exceed MAX_PATH
+ // minus 12)." Since MAX_PATH is 260, 260 - 12 = 248.
+ //
+ // The MSDN docs appear to say that a normal path that is 248 bytes long
+ // will work; empirically the path must be less then 248 bytes long.
+ if len(path) < 248 {
+ // Don't fix. (This is how Go 1.7 and earlier worked,
+ // not automatically generating the \\?\ form)
+ return path
+ }
+
+ // The extended form begins with \\?\, as in
+ // \\?\c:\windows\foo.txt or \\?\UNC\server\share\foo.txt.
+ // The extended form disables evaluation of . and .. path
+ // elements and disables the interpretation of / as equivalent
+ // to \. The conversion here rewrites / to \ and elides
+ // . elements as well as trailing or duplicate separators. For
+ // simplicity it avoids the conversion entirely for relative
+ // paths or paths containing .. elements. For now,
+ // \\server\share paths are not converted to
+ // \\?\UNC\server\share paths because the rules for doing so
+ // are less well-specified.
+ if len(path) >= 2 && path[:2] == `\\` {
+ // Don't canonicalize UNC paths.
+ return path
+ }
+ if !isAbs(path) {
+ // Relative path
+ return path
+ }
+
+ const prefix = `\\?`
+
+ pathbuf := make([]byte, len(prefix)+len(path)+len(`\`))
+ copy(pathbuf, prefix)
+ n := len(path)
+ r, w := 0, len(prefix)
+ for r < n {
+ switch {
+ case os.IsPathSeparator(path[r]):
+ // empty block
+ r++
+ case path[r] == '.' && (r+1 == n || os.IsPathSeparator(path[r+1])):
+ // /./
+ r++
+ case r+1 < n && path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])):
+ // /../ is currently unhandled
+ return path
+ default:
+ pathbuf[w] = '\\'
+ w++
+ for ; r < n && !os.IsPathSeparator(path[r]); r++ {
+ pathbuf[w] = path[r]
+ w++
+ }
+ }
+ }
+ // A drive's root directory needs a trailing \
+ if w == len(`\\?\c:`) {
+ pathbuf[w] = '\\'
+ w++
+ }
+ return string(pathbuf[:w])
+}
+
+func isAbs(path string) (b bool) {
+ v := volumeName(path)
+ if v == "" {
+ return false
+ }
+ path = path[len(v):]
+ if path == "" {
+ return false
+ }
+ return os.IsPathSeparator(path[0])
+}
+
+func volumeName(path string) (v string) {
+ if len(path) < 2 {
+ return ""
+ }
+ // with drive letter
+ c := path[0]
+ if path[1] == ':' &&
+ ('0' <= c && c <= '9' || 'a' <= c && c <= 'z' ||
+ 'A' <= c && c <= 'Z') {
+ return path[:2]
+ }
+ // is it UNC
+ if l := len(path); l >= 5 && os.IsPathSeparator(path[0]) && os.IsPathSeparator(path[1]) &&
+ !os.IsPathSeparator(path[2]) && path[2] != '.' {
+ // first, leading `\\` and next shouldn't be `\`. its server name.
+ for n := 3; n < l-1; n++ {
+ // second, next '\' shouldn't be repeated.
+ if os.IsPathSeparator(path[n]) {
+ n++
+ // third, following something characters. its share name.
+ if !os.IsPathSeparator(path[n]) {
+ if path[n] == '.' {
+ break
+ }
+ for ; n < l; n++ {
+ if os.IsPathSeparator(path[n]) {
+ break
+ }
+ }
+ return path[:n]
+ }
+ break
+ }
+ }
+ }
+ return ""
+}
diff --git a/internal/fs/fs_test.go b/internal/fs/fs_test.go
index 163b26e647..e16f772c9c 100644
--- a/internal/fs/fs_test.go
+++ b/internal/fs/fs_test.go
@@ -547,6 +547,37 @@ func TestCopyFileSymlink(t *testing.T) {
}
}
+func TestCopyFileLongFilePath(t *testing.T) {
+ if runtime.GOOS != "windows" {
+ // We want to ensure the temporary fix actually fixes the issue with
+ // os.Chmod and long file paths. This is only applicable on Windows.
+ t.Skip("skipping on non-windows")
+ }
+
+ h := test.NewHelper(t)
+ h.TempDir(".")
+
+ tmpPath := h.Path(".")
+
+ // Create a directory with a long-enough path name to cause the bug in #774.
+ dirName := ""
+ for len(tmpPath+string(os.PathSeparator)+dirName) <= 300 {
+ dirName += "directory"
+ }
+
+ h.TempDir(dirName)
+ h.TempFile(dirName+string(os.PathSeparator)+"src", "")
+
+ tmpDirPath := tmpPath + string(os.PathSeparator) + dirName + string(os.PathSeparator)
+
+ err := copyFile(tmpDirPath+"src", tmpDirPath+"dst")
+ if err != nil {
+ t.Fatalf("unexpected error while copying file: %v", err)
+ }
+}
+
+// C:\Users\appveyor\AppData\Local\Temp\1\gotest639065787\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890\dir4567890
+
func TestCopyFileFail(t *testing.T) {
if runtime.GOOS == "windows" {
// XXX: setting permissions works differently in