Fix: preview for clean when file names contain backslashes (#465)

This is a breaking change: flag arguments provided to forgit clean are
now passed to git ls-files instead of git clean -n. This change is
necessary because git clean does not have a -z option that would prevent
it from escaping file names containing backslashes. However, git ls-files
is way more flexible than git clean, so all use cases covered by git
clean (and more) should still be possible.

bin/git-forgit

@@ -608,13 +608,8 @@ _forgit_clean_preview() {
     fi
 }
 
-# git clean selector
-_forgit_clean() {
-    _forgit_inside_work_tree || return 1
-    _forgit_contains_non_flags "$@" && { git clean -q "$@"; return $?; }
-    local files opts
-    _forgit_clean_git_opts=()
-    _forgit_parse_array _forgit_clean_git_opts "$FORGIT_CLEAN_GIT_OPTS"
+_forgit_clean_select_files() {
+    local opts
     opts="
         $FORGIT_FZF_DEFAULT_OPTS
         --preview=\"$FORGIT clean_preview {}\"
@@ -622,7 +617,17 @@ _forgit_clean() {
         $FORGIT_CLEAN_FZF_OPTS
     "
     # Note: Postfix '/' in directory path should be removed. Otherwise the directory itself will not be removed.
-    files=$(git -c core.quotePath=false clean -xdffn "$@"| sed 's/^Would remove //' | FZF_DEFAULT_OPTS="$opts" fzf |sed 's#/$##')
+    _forgit_list_files --others "$@" | FZF_DEFAULT_OPTS="$opts" fzf | sed 's#/$##'
+}
+
+# git clean selector
+_forgit_clean() {
+    _forgit_inside_work_tree || return 1
+    _forgit_contains_non_flags "$@" && { git clean -q "$@"; return $?; }
+    local files
+    _forgit_clean_git_opts=()
+    _forgit_parse_array _forgit_clean_git_opts "$FORGIT_CLEAN_GIT_OPTS"
+    files=$(_forgit_clean_select_files "$@")
     [[ -n "$files" ]] && echo "$files" | tr '\n' '\0' | xargs -0 -I% git clean "${_forgit_clean_git_opts[@]}" -xdff '%' && git status --short && return
     echo 'Nothing to clean.'
 }

tests/clean-select-files.test.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+function set_up_before_script() {
+    source bin/git-forgit
+
+    # create a new git repository in a temp directory
+    cd "$(temp_dir)" || return 1
+    git init --quiet
+
+    # create files to test against
+    touch file.txt
+    touch file_with\\backslashes\\.txt
+    touch "file with spaces.txt"
+    touch "file_with\ttab.txt"
+}
+
+# @data_provider provider_clean_select_files
+function test_forgit_clean_select_files_preview() {
+    mock "fzf" "sed -n ${1}p"
+
+    local file
+    file=$(_forgit_clean_select_files)
+
+    assert_file_exists "$file"
+}
+
+ function provider_clean_select_files() {
+     data_set 1
+     data_set 2
+     data_set 3
+     data_set 4
+ }