[PATCH 1/2] _pandoc: do not use chache, allow multiple extensions for format

["Jun. T" <takimoto-j@xxxxxxxxxxxxxxxxx>]

[1] If use-cache style is not on, nothing is completed for

% pandoc -f <TAB>

or for any other options that use cache (--t, --highlight-style, etc.).

[2] The options -f and -t accepts FORMAT with zero, one or more EXTENSIONs
    -f FORMAT
    -f FORMAT+EXTENSION1-EXTENSION2+EXTENSION3
but the current _pandoc can complete at most one EXTENSION.

[3] To complete FORMAT{+,-}EXTENSION, _pandoc creates a list of all the
possible pairs of FORMAT{+,-}EXTENSION by calling

    pandoc --list-extensions=FORMAT

repeatedly for all the supported FORMATs (more than 60 FORMATs).
This may take some time, and I guess this is the reason that the
use-cache is required.

With this patch, "pandoc --list-extensions=FORMAT" is called only once
after the FORMAT-part has been completed, and two or more EXTENSIONs
can be completed after the FORMAT.

With this change I think we don't need to use the cache.
So I removed all the cache-related stuff.

[4] "pandoc --list-extensions=markdown" gives a list of extensions like

-abbreviations
+all_symbols_escapable
-amuse
...

Here +/- indicates it is on/off by default. But the current _pandoc
offers 'abbreviations' for -f markdown-<TAB> and 'all_symbols_escapable'
for -f markdown+<TAB>; this should be the other way round.


---
 Completion/Unix/Command/_pandoc | 257 +++++++-------------------------
 1 file changed, 56 insertions(+), 201 deletions(-)

diff --git a/Completion/Unix/Command/_pandoc b/Completion/Unix/Command/_pandoc
index 0c0672aaa..97f1190be 100644
--- a/Completion/Unix/Command/_pandoc
+++ b/Completion/Unix/Command/_pandoc
@@ -1,119 +1,29 @@
 #compdef pandoc
 
-# {{{ helper: cache policy for available formats and other variables
-(( $+functions[__pandoc_cache_policy] )) ||
-__pandoc_cache_policy(){
-  local cache_file="$1"
-  if [[ -f "${commands[pandoc]}" && -f "${cache_file}" ]]; then
-    # if the manifest file is newer then the cache:
-    if [[ "${commands[pandoc]}" -nt "${cache_file}" ]]; then
-      return 0
-    else
-      return 1
-    fi
+# {{{ input or output formats with optional extensions
+# required option: -T (input|output)
+(( $+functions[_pandoc_format] )) ||
+_pandoc_format() {
+  local -a inout expl
+  zparseopts -D -E - T:=inout
+  local format=${PREFIX%%(+|-)*}
+  if compset -P '*(+|-)'; then
+    local pm=${IPREFIX[-1]}   # '+' or '-'
+    local -a extensions=(${${$(pandoc --list-extensions=$format):#$pm*}#(+|-)})
+    _wanted extensions expl 'extension' compadd -S '+' -r '-+ ' -a extensions
   else
-    return 0
+    local -a formats=( $(pandoc --list-$inout[2]-formats) )
+    _wanted formats expl 'format' compadd -S '+' -r '-+ ' -a formats
   fi
 }
 # }}}
-# {{{ choose a format among supported output format
-(( $+functions[_pandoc_output_format] )) ||
-_pandoc_output_format(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  if _cache_invalid pandoc_output_formats_simple; then
-    output_formats_simple=($(pandoc --list-output-formats))
-    _store_cache pandoc_output_formats_simple output_formats_simple
-  else
-    _retrieve_cache pandoc_output_formats_simple
-  fi
-  if _cache_invalid pandoc_output_formats_plus_extensible || _cache_invalid pandoc_output_formats_minus_extensible; then
-    for f in ${output_formats_simple[*]}; do
-      for e in $(pandoc --list-extensions=${f}); do
-        if [[ "${e}" =~ '^\+' ]]; then
-          output_formats_plus_extensible+=("${f}${e}")
-        elif [[ "${e}" =~ '^\-' ]]; then
-          output_formats_minus_extensible+=("${f}${e}")
-        fi
-      done
-    done
-    _store_cache pandoc_output_formats_minus_extensible output_formats_minus_extensible
-    _store_cache pandoc_output_formats_plus_extensible output_formats_plus_extensible
-  else
-    _retrieve_cache pandoc_output_formats_minus_extensible
-    _retrieve_cache pandoc_output_formats_plus_extensible
-  fi
-  _alternative \
-    'formats_plus:format:{_multi_parts "+" output_formats_plus_extensible}' \
-    'formats_minus:format:{_multi_parts -- "-" output_formats_minus_extensible}'
-}
-# }}}
-# {{{ choose a format among supported input format
-(( $+functions[_pandoc_input_format] )) ||
-_pandoc_input_format(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  if _cache_invalid pandoc_input_formats_simple; then
-    input_formats_simple=($(pandoc --list-input-formats))
-    _store_cache pandoc_input_formats_simple input_formats_simple
-  else
-    _retrieve_cache pandoc_input_formats_simple
-  fi
-  if _cache_invalid pandoc_input_formats_plus_extensible || _cache_invalid pandoc_input_formats_minus_extensible; then
-    for f in ${input_formats_simple[*]}; do
-      for e in $(pandoc --list-extensions=${f}); do
-        if [[ "${e}" =~ '^\+' ]]; then
-          input_formats_plus_extensible+=("${f}${e}")
-        elif [[ "${e}" =~ '^\-' ]]; then
-          input_formats_minus_extensible+=("${f}${e}")
-        fi
-      done
-    done
-    _store_cache pandoc_input_formats_minus_extensible input_formats_minus_extensible
-    _store_cache pandoc_input_formats_plus_extensible input_formats_plus_extensible
-  else
-    _retrieve_cache pandoc_input_formats_minus_extensible
-    _retrieve_cache pandoc_input_formats_plus_extensible
-  fi
-  _alternative \
-    'formats_plus:format:{_multi_parts "+" input_formats_plus_extensible}' \
-    'formats_minus:format:{_multi_parts -- "-" input_formats_minus_extensible}'
-}
-# }}}
-# {{{ choose a format among all supported formats
+# {{{ all supported formats
 (( $+functions[_pandoc_all_formats] )) ||
 _pandoc_all_formats(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  if _cache_invalid pandoc_input_formats_simple; then
-    input_formats_simple=($(pandoc --list-input-formats))
-    _store_cache pandoc_input_formats_simple input_formats_simple
-  else
-    _retrieve_cache pandoc_input_formats_simple
-  fi
-  if _cache_invalid pandoc_output_formats_simple; then
-    output_formats_simple=($(pandoc --list-output-formats))
-    _store_cache pandoc_output_formats_simple output_formats_simple
-  else
-    _retrieve_cache pandoc_output_formats_simple
-  fi
-  if _cache_invalid pandoc_all_formats; then
-    all_formats=(${output_formats_simple} ${input_formats_simple})
-    all_formats=($(sort -u <<<"${all_formats[*]}"))
-    _store_cache pandoc_all_formats all_formats
-  else
-    _retrieve_cache pandoc_all_formats
-  fi
-  _describe "format" all_formats
+  local -a expl
+  local -aU formats
+  formats=( $(pandoc --list-input-formats) $(pandoc --list-output-formats) )
+  _wanted formats expl 'format' compadd -a formats
 }
 # }}}
 # {{{ pdf engine choice
@@ -141,113 +51,58 @@ _pandoc_pdf_engine_opts(){
   esac
 }
 # }}}
-# {{{ choose data-dir
-(( $+functions[_pandoc_data_dir] )) ||
-_pandoc_data_dir(){
-  _files -/
+# {{{ data-dir specified by --data-dir option, or the default dir
+_pandoc_default_dir() {
+  if (( $+opt_args[--data-dir] )); then
+    echo ${opt_args[--data-dir]:a}
+  else
+    # XXX Some versions of pandoc may output two user data directories:
+    #          ~/.local/share/pandoc or ~/.pandoc
+    #     Here we use only the first one.
+    pandoc --version | sed -ne 's/.*[Uu]ser data directory: \([^ ]*\).*/\1/p'
+  fi
 }
-# }}}
-# {{{ choose template from data-dir
+# {{{ template file in $PWD or data-dir/templates/, or URL
 (( $+functions[_pandoc_template] )) ||
 _pandoc_template(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  if _cache_invalid pandoc_output_formats_simple; then
-    output_formats_simple=($(pandoc --list-output-formats))
-    _store_cache pandoc_output_formats_simple output_formats_simple
-  else
-    _retrieve_cache pandoc_output_formats_simple
-  fi
-  local data_dir=${opt_args[--data-dir]}
-  if [[ -z $data_dir ]]; then
-    if _cache_invalid pandoc_default_data_dir; then
-      default_data_dir=$(pandoc --version | sed -ne 's/Default user data directory: \(.*\)/\1/p')
-      _store_cache pandoc_default_data_dir default_data_dir
-    else
-      _retrieve_cache pandoc_default_data_dir
-    fi
-    data_dir=${default_data_dir}
-  fi
-  _pandoc_template_find_args="-name '*.'${output_formats_simple[1]}"
-  for ((i = 2; i < ${#output_formats_simple[@]}; i++ )); do
-    _pandoc_template_find_args=$_pandoc_template_find_args" -or -name '*.'${output_formats_simple[$i]}"
-  done
-  templates=($(eval find -L ${data_dir}/templates ${_pandoc_template_find_args} 2>/dev/null | sed -e 's/.*\///' -e 's/\.[^.]*$//'))
-  if [[ -z "${templates}" ]]; then
-    templates=default
-  fi
-  _describe 'templates from default data-dir' templates
+  # find output format from '-t format' or '-o xxx.format'
+  local format=${${(v)opt_args[(i)(-t|--to|-w|--write)]}%%(+|-)*}
+  [[ -z $format ]] && format=${(v)opt_args[(i)(-o|--output)]:e}
+  local pat="'*'"   # or '*.*' ?
+  [[ -n $format ]] && pat="'*.$format'"
+  local template_dir=$(_pandoc_default_dir)/templates
+  _alternative \
+    "local-templates:local template:_files -g $pat" \
+    "data-dir-templates:template in data-dir:_files -W $template_dir -g $pat" \
+    'urls: :_urls'
 }
 # }}}
 # {{{ choose highlight-style
 (( $+functions[_pandoc_highlight_style] )) ||
 _pandoc_highlight_style(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  if _cache_invalid pandoc_highlighting_styles; then
-    highlighting_styles=($(pandoc --list-highlight-styles))
-    _store_cache pandoc_highlighting_styles highlighting_styles
-  else
-    _retrieve_cache pandoc_highlighting_styles
-  fi
   _alternative \
-    'styles:style:{_values "syntax builting style" ${highlighting_styles[*]}}' \
-    'style_files_here:style:{_files -g "*.theme"}'
+    'styles:style:( $(pandoc --list-highlight-styles) )' \
+    'style-files:style file:_files -g "*.theme"'
 }
 # }}}
-# {{{ choose filter from specified or default data-dir
+# {{{ filter file in $PWD, data-dir/filters/ or $PATH
 (( $+functions[_pandoc_filter] )) ||
 _pandoc_filter(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  local data_dir=${opt_args[--data-dir]}
-  if [[ -z $data_dir ]]; then
-    if _cache_invalid pandoc_default_data_dir; then
-      default_data_dir=$(pandoc --version | sed -ne 's/Default user data directory: \(.*\)/\1/p')
-      _store_cache pandoc_default_data_dir default_data_dir
-    else
-      _retrieve_cache pandoc_default_data_dir
-    fi
-    data_dir=${default_data_dir}
-  fi
-  local filters_dir=$data_dir"/filters"
+  local filters_dir=$(_pandoc_default_dir)/filters
   _alternative \
-    'local_filter:filter:{_files -g "*.lua"}' \
-    'data_dir_filter:filter:{_files -W filters_dir -g "*.lua"}'
+    'local-filters:local filter:_files' \
+    'data-dir-filters:filter in data-dir:_files -W filters_dir' \
+    'commands: : _command_names -e'
 }
 # }}}
-# {{{ choose lua filter from specified or default data-dir
+# {{{ lua filter in $PWD or data-dir/filters/
 (( $+functions[_pandoc_lua_filter] )) ||
 _pandoc_lua_filter(){
-  local update_policy
-  zstyle -s ":completion:${curcontext}:" cache-policy update_policy
-  if [[ -z "$update_policy" ]]; then
-    zstyle ":completion:${curcontext}:" cache-policy __pandoc_cache_policy
-  fi
-  local data_dir=${opt_args[--data-dir]}
-  if [[ -z $data_dir ]]; then
-    if _cache_invalid pandoc_default_data_dir; then
-      default_data_dir=$(pandoc --version | sed -ne 's/Default user data directory: \(.*\)/\1/p')
-      _store_cache pandoc_default_data_dir default_data_dir
-    else
-      _retrieve_cache pandoc_default_data_dir
-    fi
-    data_dir=${default_data_dir}
-  fi
-  local filters_dir=$data_dir"/filters"
+  local filters_dir=$(_pandoc_default_dir)/filters
   _alternative \
-    'local_filter:filter:{_files -g "(#q*)(.)"}' \
-    'data_dir_filter:filter:{_files -W filters_dir -g "(#q*)(.)"}'
-  }
+    'local-filters:local filter:_files -g "*.lua"' \
+    'data-dir-filters:filter in data-dir:_files -W filters_dir -g "*.lua"'
+}
 # }}}
 # {{{ choose reference location
 (( $+functions[_pandoc_reference_location] )) ||
@@ -328,11 +183,11 @@ _pandoc_track_changes() {
 # }}}
 
 # The real thing
-_arguments -C \
-  {-f,-r,--from=,--read=}'[specify input format]:format:_pandoc_input_format' \
-  {-t,-w,--to=,--write=}'[specify output format]:format:_pandoc_output_format' \
+_arguments -s \
+  {-f+,-r+,--from=,--read=}'[specify input format]: :_pandoc_format -T input' \
+  {-t+,-w+,--to=,--write=}'[specify output format]: :_pandoc_format -T output' \
   {-o,--output=}'[write output to FILE instead of stdout]:file:_files' \
-  '--data-dir=[specify the user data directory to search for pandoc data files]:dir:_pandoc_data_dir' \
+  '--data-dir=[specify the user data directory to search for pandoc data files]:data directory:_files -/' \
   '--base-header-level=[specify the base level for headers (defaults to 1)]:number:_pandoc_header_level' \
   '--strip-empty-paragraphs[deprecated. Use the +empty_paragraphs extension instead]: :' \
   '--indented-code-classes=[classes to use for indented code blocks]:class:{_message "Classes separated with ,"}' \
@@ -347,7 +202,7 @@ _arguments -C \
   '--template=[use FILE as a custom template for the generated document. Implies --standalone]: :_pandoc_template' \
   {\*-M,\*--metadata=}'[set the metadata field KEY to the value VALUE]:key\:value: ' \
   {\*-V,\*--variable=}'[set the variable KEY to the value VALUE]:key\:value: ' \
-  '(- :)'{-D,--print-default-template=}'[print the system default template for an output]:format:_pandoc_output_format' \
+  '(- :)'{-D+,--print-default-template=}"[print the system default template for an output]:format:( $(pandoc --list-output-formats) )" \
   '(- :)--print-default-data-file=[print a system default data file]:file: ' \
   '(- :)--print-highlight-style=[prints a JSON version of a highlighting style]:style|file: ' \
   '--dpi=[specify the dpi (dots per inch) value for conversion from pixels to inch/centimeters and vice versa]:number: ' \
-- 
2.21.1 (Apple Git-122.3)