feat(tar): use long option compression options

Previously we only used single letter options to decide what file
extensions to complete for extracting archives, make it also consider
long options (gnu style).

Co-Authored-By: Koichi Murase <myoga.murase@gmail.com>

completions/tar

@@ -205,10 +205,15 @@ _comp_cmd_tar__preparse_cmdline()
         case "$i" in
             --delete | --test-label | --catenate | --concatenate | --extract | --get | --update | --list | --append | --create)
                 tar_mode=${i:2:100}
-                # FIXME: We don't set $tar_mode_arg since it's used for combined
-                #        single letter options, but that means we don't handle
-                #        compression formats.
-                break
+                ;;
+            --bzip2 | --xz | --lzip | --lzma | --lzop | --zstd)
+                tar_compression_mode=${i:2:100}
+                ;;
+            --gzip | --gunzip | --ungzip)
+                tar_compression_mode="gzip"
+                ;;
+            --compress | --uncompress)
+                tar_compression_mode="compress"
                 ;;
             --*)
                 # skip
@@ -439,10 +444,15 @@ _comp_cmd_tar__cleanup_prev()
     fi
 }
 
+_comp_cmd_tar__is_bsdtar()
+{
+    [[ ${COMP_WORDS[0]} == ?(*/)bsdtar ]]
+}
+
 _comp_cmd_tar__detect_ext()
 {
     local tars='@(@(tar|spkg)?(.@(Z|[bgx]z|bz2|lz?(ma|o)|zst))|t@([abglx]z|b?(z)2|zst)|cbt|gem|xbps)'
-    if [[ ${COMP_WORDS[0]} == ?(*/)bsdtar ]]; then
+    if _comp_cmd_tar__is_bsdtar; then
         # https://github.com/libarchive/libarchive/wiki/LibarchiveFormats
         tars=${tars/%\)/|pax|cpio|iso|zip|@(j|x)ar|mtree|a|7z|warc}
         if _comp_cmd_tar__extract_like_mode; then
@@ -455,33 +465,44 @@ _comp_cmd_tar__detect_ext()
     fi
     ext="$tars"
 
-    case "$tar_mode_arg" in
-        --*)
-            # FIXME: get correct extensions for long options (gnu style)
-            ;;
-        ?(-)*[cr]*f)
+    if ! _comp_cmd_tar__extract_like_mode; then
+        if ! _comp_cmd_tar__is_bsdtar; then
             ext='@(tar|gem|spkg|cbt|xpbs)'
-            case ${words[1]} in
-                *a*) ext="$tars" ;;
-                *z*) ext='t?(ar.)gz' ;;
-                *Z*) ext='ta@(r.Z|z)' ;;
-                *[jy]*) ext='t@(?(ar.)bz?(2)|b2)' ;;
-                *J*) ext='t?(ar.)xz' ;;
-            esac
-            ;;
-        +([^ZzJjy])f)
-            # Pass through using defaults above
-            ;;
-        *[Zz]*f)
-            ext='@(@(t?(ar.)|spkg.)@(gz|Z)|taz)'
-            ;;
-        *[jy]*f)
-            ext='@(t?(ar.)bz?(2)|spkg|tb2)'
-            ;;
-        *[J]*f)
-            ext='@(@(tar|spkg).@(lzma|xz)|t[lx]z)'
-            ;;
-    esac
+        fi
+        case $tar_mode_arg:$tar_compression_mode in
+            *a*:none | *:auto-compress)
+                ext="$tars"
+                ;;
+            *z*:none | *:gzip)
+                ext='t?(ar.)gz'
+                ;;
+            *Z*:none | *:compress)
+                ext='ta@(r.Z|z)'
+                ;;
+            *[jy]*:none | *:bzip2)
+                ext='t@(?(ar.)bz?(2)|b2)'
+                ;;
+            *J*:none | *:xz)
+                ext='t?(ar.)xz'
+                ;;
+        esac
+    else
+        #TODO: lzip, lzma, lzop
+        case $tar_mode_arg:$tar_compression_mode in
+            *[Zz]*f:none | *:gzip | *:compress)
+                ext='@(@(t?(ar.)|spkg.)@(gz|Z)|taz)'
+                ;;
+            *[jy]*f:none | *:bzip2)
+                ext='@(t?(ar.)bz?(2)|spkg|tb2)'
+                ;;
+            *J*f:none | *:xz)
+                ext='@(@(tar|spkg).@(lzma|xz)|t[lx]z)'
+                ;;
+            *:zstd)
+                ext='t?(ar.)zst'
+                ;;
+        esac
+    fi
 }
 
 _comp_cmd_tar__gnu()
@@ -496,9 +517,11 @@ _comp_cmd_tar__gnu()
     local tar_mode=none
 
     # The mode argument, e.g. -cpf or -c
-    # FIXME: handle long options
     local tar_mode_arg=
 
+    # Compression mode - from long options
+    local tar_compression_mode=none
+
     if [[ -v _comp_cmd_tar__debug ]]; then
         set -x
         local PS4='$BASH_SOURCE:$LINENO: '
@@ -683,6 +706,9 @@ _comp_cmd_tar__posix()
     # The mode argument, e.g. -cpf or -c
     local tar_mode_arg=
 
+    # Compression mode - from long options
+    local tar_compression_mode=none
+
     local cur prev words cword was_split comp_args
 
     _comp_initialize -s -- "$@" || return

test/t/test_tar.py

@@ -127,4 +127,9 @@ def test_23(self, completion):
     def test_24(self, completion):
         assert completion == "archive.tar.xz dir/ dir2/".split()
 
+    # Test compression detection of gnu style options
+    @pytest.mark.complete("tar --extract --xz --file ", cwd="tar")
+    def test_25(self, completion):
+        assert completion == "archive.tar.xz dir/ dir2/".split()
+
     # TODO: "tar tf escape.tar a/b"