git-prompt: Document GIT_PS1_DESCRIBE_STYLE

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index 29b1ec9eb1797e0f2c3c9f7067222432150ba85f..5ab488cd65a40abeb211ed5934bd4741972cd556 100644 (file)
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -34,9 +34,10 @@
 #
 # If you would like to see the difference between HEAD and its upstream,
 # set GIT_PS1_SHOWUPSTREAM="auto".  A "<" indicates you are behind, ">"
-# indicates you are ahead, and "<>" indicates you have diverged.  You
-# can further control behaviour by setting GIT_PS1_SHOWUPSTREAM to a
-# space-separated list of values:
+# indicates you are ahead, "<>" indicates you have diverged and "="
+# indicates that there is no difference. You can further control
+# behaviour by setting GIT_PS1_SHOWUPSTREAM to a space-separated list
+# of values:
 #
 #     verbose       show number of commits ahead/behind (+/-) upstream
 #     legacy        don't use the '--count' option available in recent
@@ -48,6 +49,15 @@
 # find one, or @{upstream} otherwise.  Once you have set
 # GIT_PS1_SHOWUPSTREAM, you can override it on a per-repository basis by
 # setting the bash.showUpstream config variable.
+#
+# If you would like to see more information about the identity of
+# commits checked out as a detached HEAD, set GIT_PS1_DESCRIBE_STYLE
+# to one of these values:
+#
+#     contains      relative to newer annotated tag (v1.6.3.2~35)
+#     branch        relative to newer tag or branch (master~4)
+#     describe      relative to older annotated tag (v1.6.3.1-13-gdd42c2f)
+#     default       exactly matching tag
 
 # __gitdir accepts 0 or 1 arguments (i.e., location)
 # returns location of .git repo