From 64fd98a2bdd18cf78650cd6cabdac651d37a8a13 Mon Sep 17 00:00:00 2001
From: Thomas Lauf <thomas.lauf@tngtech.com>
Date: Thu, 27 Sep 2018 22:02:15 +0200
Subject: [PATCH] Add help and man page for command 'undo'

---
 doc/man/timew-undo.1.in  | 15 +++++++++++++++
 src/commands/CmdHelp.cpp | 16 ++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 doc/man/timew-undo.1.in

diff --git a/doc/man/timew-undo.1.in b/doc/man/timew-undo.1.in
new file mode 100644
index 00000000..72798520
--- /dev/null
+++ b/doc/man/timew-undo.1.in
@@ -0,0 +1,15 @@
+.TH timew-undo 1 2018-02-03 "${PACKAGE_STRING}" "User Manuals"
+.
+.SH NAME
+timew-undo \- revert Timewarrior commands
+.
+.SH SYNOPSIS
+.B timew undo
+.
+.SH DESCRIPTION
+The 'undo' command is used to revert the action of Timewarrior commands.
+Only commands affecting intervals or Timewarrior configuration can be reverted.
+Timewarrior keeps a journal of changes to the interval database and Timewarrior configuration.
+A call to 'undo' removes the last entry in the journal and restores the previous state.
+As long as there are entries in the journal, you can revert the respective action.
+The 'undo' command itself cannot be undone!
\ No newline at end of file
diff --git a/src/commands/CmdHelp.cpp b/src/commands/CmdHelp.cpp
index fcf159a2..9c30e02b 100644
--- a/src/commands/CmdHelp.cpp
+++ b/src/commands/CmdHelp.cpp
@@ -63,6 +63,7 @@ int CmdHelpUsage (const Extensions& extensions)
             << "       timew tag @<id> [@<id> ...] <tag> [<tag> ...]\n"
             << "       timew tags [<interval>] [<tag> ...]\n"
             << "       timew track <interval> [<tag> ...]\n"
+            << "       timew undo\n"
             << "       timew untag @<id> [@<id> ...] <tag> [<tag> ...]\n"
             << "       timew week [<interval>] [<tag> ...]\n"
             << '\n';
@@ -900,6 +901,21 @@ int CmdHelp (
                 << "same as the 'start' command.\n"
                 << '\n';
 
+    // Ruler                 1         2         3         4         5         6         7         8
+    //              12345678901234567890123456789012345678901234567890123456789012345678901234567890
+    else if (words[0] == "undo")
+    {
+      std::cout << '\n'
+                << "Syntax: timew undo\n"
+                << '\n'
+                << "The 'undo' command is used to revert the action of Timewarrior commands. Only\n"
+                << "commands affecting intervals or Timewarrior configuration can be reverted.\n"
+                << "Timewarrior keeps a journal of changes to the interval database and Timewarrior\n"
+                << "configuration. A call to 'undo' removes the last entry in the journal and\n"
+                << "restores the previous state. As long as there are entries in the journal, you\n"
+                << "can revert the respective action. The 'undo' command itself cannot be undone!"
+                << '\n';
+    }
     // Ruler                 1         2         3         4         5         6         7         8
     //              12345678901234567890123456789012345678901234567890123456789012345678901234567890
     else if (words[0] == "untag")