diff -r 5e4027db52f4 -r bfcd5c7cbf9a mercurial/commands.py
--- a/mercurial/commands.py	Wed Jul 11 21:51:47 2018 +0900
+++ b/mercurial/commands.py	Wed Jul 11 22:06:04 2018 +0900
@@ -2515,12 +2515,11 @@
     Search revision history for a regular expression in the specified
     files or the entire project.
 
-    By default, grep searches the expression on the working directory.
-    To search history and show the most recent revision number for each
-    file in which it finds a match, use :hg:`grep -r tip:0`.
-    To get it to print every revision that contains a change in match status
-    ("-" for a match that becomes a non-match, or "+" for a non-match that
-    becomes a match), use the --diff flag.
+    By default, grep prints the most recent revision number for each
+    file in which it finds a match. To get it to print every revision
+    that contains a change in match status ("-" for a match that becomes
+    a non-match, or "+" for a non-match that becomes a match), use the
+    --diff flag.
 
     PATTERN can be any Python (roughly Perl-compatible) regular
     expression.