Support git-crypt (#168)

Support is inherently provided by `enter`, which now supports a command.
I've added a `git-crypt` command, which is really just an alias
under-the-hood for "enter git-crypt".

test/conftest.py

@@ -89,6 +89,7 @@ def supported_commands():
         'decrypt',
         'encrypt',
         'enter',
+        'git-crypt',
         'gitconfig',
         'help',
         'init',

test/test_git_crypt.py

@@ -0,0 +1,42 @@
+"""Test git-crypt"""
+
+import pytest
+
+
+@pytest.mark.parametrize(
+    'crypt',
+    [False, 'installed', 'installed-but-failed'],
+    ids=['not-installed', 'installed', 'installed-but-failed']
+)
+def test_git_crypt(runner, yadm, paths, tmpdir, crypt):
+    """git-crypt tests"""
+
+    paths.repo.ensure(dir=True)
+    bindir = tmpdir.mkdir('bin')
+    pgm = bindir.join('test-git-crypt')
+
+    if crypt:
+        pgm.write(f'#!/bin/sh\necho git-crypt ran\n')
+        pgm.chmod(0o775)
+    if crypt == 'installed-but-failed':
+        pgm.write('false\n', mode='a')
+
+    script = f"""
+        YADM_TEST=1 source {yadm}
+        YADM_REPO={paths.repo}
+        GIT_CRYPT_PROGRAM="{pgm}"
+        git_crypt "param1"
+    """
+
+    run = runner(command=['bash'], inp=script)
+
+    if crypt:
+        if crypt == 'installed-but-failed':
+            assert run.failure
+        else:
+            assert run.success
+        assert run.out.strip() == 'git-crypt ran'
+    else:
+        assert run.failure
+        assert f"command '{pgm}' cannot be located" in run.out
+    assert run.err == ''

yadm

@@ -41,6 +41,7 @@ FULL_COMMAND=""
 GPG_PROGRAM="gpg"
 GIT_PROGRAM="git"
 AWK_PROGRAM=("gawk" "awk")
+GIT_CRYPT_PROGRAM="git-crypt"
 J2CLI_PROGRAM="j2"
 ENVTPL_PROGRAM="envtpl"
 LSB_RELEASE_PROGRAM="lsb_release"
@@ -76,16 +77,20 @@ function main() {
 
   # parse command line arguments
   local retval=0
-  internal_commands="^(alt|bootstrap|clean|clone|config|decrypt|encrypt|enter|help|init|introspect|list|perms|upgrade|version)$"
+  internal_commands="^(alt|bootstrap|clean|clone|config|decrypt|encrypt|enter|git-crypt|help|init|introspect|list|perms|upgrade|version)$"
   if [ -z "$*" ] ; then
     # no argumnts will result in help()
     help
   elif [[ "$1" =~ $internal_commands ]] ; then
     # for internal commands, process all of the arguments
-    YADM_COMMAND="$1"
+    YADM_COMMAND="${1/-/_}"
     YADM_ARGS=()
     shift
 
+    # commands listed below do not process any of the parameters
+    if [[ "$YADM_COMMAND" =~ ^(enter|git_crypt)$ ]] ; then
+      YADM_ARGS=("$@")
+    else
       while [[ $# -gt 0 ]] ; do
         key="$1"
         case $key in
@@ -115,6 +120,7 @@ function main() {
         esac
         shift
       done
+    fi
     [ ! -d "$YADM_WORK" ] && error_out "Work tree does not exist: [$YADM_WORK]"
     HOOK_COMMAND="$YADM_COMMAND"
     invoke_hook "pre"
@@ -901,6 +907,11 @@ function encrypt() {
 
 }
 
+function git_crypt() {
+  require_git_crypt
+  enter "${GIT_CRYPT_PROGRAM} $*"
+}
+
 function enter() {
   command="$*"
   require_shell
@@ -983,6 +994,8 @@ Commands:
   yadm encrypt               - Encrypt files
   yadm decrypt [-l]          - Decrypt files
   yadm perms                 - Fix perms for private files
+  yadm enter [COMMAND]       - Run sub-shell with GIT variables set
+  yadm git-crypt [OPTIONS]   - Run git-crypt commands for the yadm repo
 
 Files:
   \$HOME/.config/yadm/config    - yadm's configuration file
@@ -1037,6 +1050,7 @@ decrypt
 encrypt
 enter
 gitconfig
+git-crypt
 help
 init
 introspect
@@ -1842,6 +1856,10 @@ function require_repo() {
 function require_shell() {
   [ -x "$SHELL" ] || error_out "\$SHELL does not refer to an executable."
 }
+function require_git_crypt() {
+  command -v "$GIT_CRYPT_PROGRAM" &> /dev/null ||
+    error_out "This functionality requires git-crypt to be installed, but the command '$GIT_CRYPT_PROGRAM' cannot be located."
+}
 function bootstrap_available() {
   [ -f "$YADM_BOOTSTRAP" ] && [ -x "$YADM_BOOTSTRAP" ] && return
   return 1