diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index 1e097dd96f3..8bcbd3f7647 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -1708,6 +1708,10 @@
 // error. (The go command's standard error is reserved for printing
 // errors building the tests.)
 //
+// The go command places $GOROOT/bin at the beginning of $PATH
+// in the test's environment, so that tests that execute
+// 'go' commands use the same 'go' as the parent 'go test' command.
+//
 // Go test runs in two different modes:
 //
 // The first, called local directory mode, occurs when go test is