Support specifying a command after `yadm enter`

test/test_enter.py

@@ -58,8 +58,9 @@ def test_enter(runner, yadm_y, paths, shell, success):
         'csh',
         'zsh',
     ])
+@pytest.mark.parametrize('cmd', [False, True], ids=['no-cmd', 'cmd'])
 @pytest.mark.usefixtures('ds1_copy')
-def test_enter_shell_ops(runner, yadm_y, paths, shell, opts, path):
+def test_enter_shell_ops(runner, yadm_y, paths, shell, opts, path, cmd):
     """Enter tests for specific shell options"""
 
     # Create custom shell to detect options passed
@@ -67,11 +68,24 @@ def test_enter_shell_ops(runner, yadm_y, paths, shell, opts, path):
     custom_shell.write('#!/bin/sh\necho OPTS=$*\necho PROMPT=$PROMPT')
     custom_shell.chmod(0o775)
 
+    test_cmd = ['test1', 'test2', 'test3']
+
+    enter_cmd = ['enter']
+    if cmd:
+        enter_cmd += test_cmd
+
     env = os.environ.copy()
     env['SHELL'] = custom_shell
 
-    run = runner(command=yadm_y('enter'), env=env)
+    run = runner(command=yadm_y(*enter_cmd), env=env)
     assert run.success
     assert run.err == ''
     assert f'OPTS={opts}' in run.out
     assert f'PROMPT=yadm shell ({paths.repo}) {path} >' in run.out
+    if cmd:
+        assert '-c ' + ' '.join(test_cmd) in run.out
+        assert 'Entering yadm repo' not in run.out
+        assert 'Leaving yadm repo' not in run.out
+    else:
+        assert 'Entering yadm repo' in run.out
+        assert 'Leaving yadm repo' in run.out

yadm

@@ -900,6 +900,7 @@ function encrypt() {
 }
 
 function enter() {
+  command="$*"
   require_shell
   require_repo
 
@@ -913,12 +914,17 @@ function enter() {
     shell_path="%~"
   fi
 
-  echo "Entering yadm repo"
+  shell_cmd=()
+  if [ -n "$command" ]; then
+    shell_cmd=('-c' "$*")
+  fi
+
+  [ "${#shell_cmd[@]}" -eq 0 ] && echo "Entering yadm repo"
 
   yadm_prompt="yadm shell ($YADM_REPO) $shell_path > "
-  PROMPT="$yadm_prompt" PS1="$yadm_prompt" "$SHELL" $shell_opts
+  PROMPT="$yadm_prompt" PS1="$yadm_prompt" "$SHELL" $shell_opts "${shell_cmd[@]}"
 
-  echo "Leaving yadm repo"
+  [ "${#shell_cmd[@]}" -eq 0 ] && echo "Leaving yadm repo"
 }
 
 function git_command() {

yadm.1

@@ -47,7 +47,7 @@ list
 
 .BR yadm " encrypt
 
-.BR yadm " enter
+.BR yadm " enter [ command ]
 
 .BR yadm " decrypt
 .RB [ -l ]
@@ -187,10 +187,14 @@ See the ENCRYPTION section for more details.
 Run a sub-shell with all Git variables set. Exit the sub-shell the same way you
 leave your normal shell (usually with the "exit" command). This sub-shell can
 be used to easily interact with your yadm repository using "git" commands. This
-could be useful if you are using a tool which uses Git directly.
+could be useful if you are using a tool which uses Git directly, such as tig,
+vim-fugitive, git-cola, etc.
 
-For example, Emacs Tramp and Magit can manage files by using this
-configuration:
+Optionally, you can provide a command after "enter", and instead of invoking
+your shell, that command will be run with all of the Git variables exposed to
+the command's environment.
+
+Emacs Tramp and Magit can manage files by using this configuration:
 
 .RS
     (add-to-list 'tramp-methods