From 25fa3abe999ea0e9d3fb10b79da343bec9ecb8fd Mon Sep 17 00:00:00 2001
From: Ingo Karkat <swdev@ingo-karkat.de>
Date: Fri, 18 May 2018 21:41:35 +0200
Subject: [PATCH] Extract generic ingo#plugin#cmdcomplete#MakeCompleteFunc()

This removes a bit of duplication in the existing two functions in this module, and the functionality is useful on its own to some clients.
---
 README.md                            |  1 +
 autoload/ingo/plugin/cmdcomplete.vim | 73 ++++++++++++++++++----------
 doc/ingo-library.txt                 |  1 +
 3 files changed, 50 insertions(+), 25 deletions(-)

diff --git a/README.md b/README.md
index 42107d6..5716d8f 100644
--- a/README.md
+++ b/README.md
@@ -93,6 +93,7 @@ HISTORY
 - Add ingo/lists/find.vim module.
 - Add ingo/folds/containment.vim module.
 - Add ingo/ftplugin/setting.vim module.
+- Extract generic ingo#plugin#cmdcomplete#MakeCompleteFunc().
 
 ##### 1.034   13-Feb-2018
 - Add ingo/regexp/split.vim module.
diff --git a/autoload/ingo/plugin/cmdcomplete.vim b/autoload/ingo/plugin/cmdcomplete.vim
index fa6d26e..d9a16d6 100644
--- a/autoload/ingo/plugin/cmdcomplete.vim
+++ b/autoload/ingo/plugin/cmdcomplete.vim
@@ -2,7 +2,7 @@
 "
 " DEPENDENCIES:
 "
-" Copyright: (C) 2013-2017 Ingo Karkat
+" Copyright: (C) 2013-2018 Ingo Karkat
 "   The VIM LICENSE applies to this script; see ':help copyright'.
 "
 " Maintainer:	Ingo Karkat <ingo@karkat.de>
@@ -10,25 +10,27 @@ let s:save_cpo = &cpo
 set cpo&vim
 
 let s:completeFuncCnt = 0
-function! ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc( argumentList, ... )
+function! ingo#plugin#cmdcomplete#MakeCompleteFunc( implementation, ... )
 "******************************************************************************
 "* PURPOSE:
-"   Define a complete function for :command -complete=customlist that completes
-"   from a static list of possible arguments.
+"   Generically define a complete function for :command -complete=customlist
+"   with a:implementation as the function body.
 "* USAGE:
-"   call ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc(
-"   \   ['foo', 'fox', 'bar'], 'FooCompleteFunc')
+"   call ingo#plugin#cmdcomplete#MakeCompleteFunc(
+"   \   'return a:ArgLead ==? "f" ? "Foo" : "Bar"', 'FooCompleteFunc')
 "   command! -complete=customlist,FooCompleteFunc Foo ...
 "	or alternatively
 "   execute 'command! -complete=customlist,' .
-"	ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc(
-"	\   ['foo', 'fox', 'bar']) . 'Foo ...'
+"	ingo#plugin#cmdcomplete#MakeCompleteFunc(
+"	\   'return a:ArgLead ==? "f" ? "Foo" : "Bar"') 'Foo ...'
 "* ASSUMPTIONS / PRECONDITIONS:
 "   None.
 "* EFFECTS / POSTCONDITIONS:
 "   Defines function.
 "* INPUTS:
-"   a:argumentList  List of possible arguments.
+"   a:implementation    String representing the function body of the completion
+"                       function. It can refer to the completion arguments
+"                       a:ArgLead, a:CmdLine, a:CursorPos.
 "   a:funcName      Optional name for the complete function; when not specified,
 "		    a unique name is generated.
 "* RETURN VALUES:
@@ -43,12 +45,42 @@ function! ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc( argumentList, ... )
 
     execute
     \   printf('function! %s( ArgLead, CmdLine, CursorPos )', l:funcName) . "\n" .
-    \   printf('    return filter(%s, ''v:val =~ "\\V\\^" . escape(a:ArgLead, "\\")'')', string(a:argumentList)) . "\n" .
-    \          'endfunction'
+    \       a:implementation . "\n" .
+    \       'endfunction'
 
     return l:funcName
 endfunction
 
+function! ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc( argumentList, ... )
+"******************************************************************************
+"* PURPOSE:
+"   Define a complete function for :command -complete=customlist that completes
+"   from a static list of possible arguments.
+"* USAGE:
+"   call ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc(
+"   \   ['foo', 'fox', 'bar'], 'FooCompleteFunc')
+"   command! -complete=customlist,FooCompleteFunc Foo ...
+"	or alternatively
+"   execute 'command! -complete=customlist,' .
+"	ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc(
+"	\   ['foo', 'fox', 'bar']) 'Foo ...'
+"* ASSUMPTIONS / PRECONDITIONS:
+"   None.
+"* EFFECTS / POSTCONDITIONS:
+"   Defines function.
+"* INPUTS:
+"   a:argumentList  List of possible arguments.
+"   a:funcName      Optional name for the complete function; when not specified,
+"		    a unique name is generated.
+"* RETURN VALUES:
+"   Name of the defined complete function.
+"******************************************************************************
+    return call('ingo#plugin#cmdcomplete#MakeCompleteFunc',
+    \   [printf('return filter(%s, ''v:val =~ "\\V\\^" . escape(a:ArgLead, "\\")'')', string(a:argumentList))] +
+    \   a:000
+    \)
+endfunction
+
 function! ingo#plugin#cmdcomplete#MakeListExprCompleteFunc( argumentExpr, ... )
 "******************************************************************************
 "* PURPOSE:
@@ -61,7 +93,7 @@ function! ingo#plugin#cmdcomplete#MakeListExprCompleteFunc( argumentExpr, ... )
 "	or alternatively
 "   execute 'command! -complete=customlist,' .
 "	ingo#plugin#cmdcomplete#MakeFixedListCompleteFunc(
-"	\   'map(copy(g:values), "v:val[0:3]")') ...
+"	\   'map(copy(g:values), "v:val[0:3]")') 'Foo ...'
 "* ASSUMPTIONS / PRECONDITIONS:
 "   None.
 "* EFFECTS / POSTCONDITIONS:
@@ -74,19 +106,10 @@ function! ingo#plugin#cmdcomplete#MakeListExprCompleteFunc( argumentExpr, ... )
 "* RETURN VALUES:
 "   Name of the defined complete function.
 "******************************************************************************
-    if a:0
-	let l:funcName = a:1
-    else
-	let s:completeFuncCnt += 1
-	let l:funcName = printf('CompleteFunc%d', s:completeFuncCnt)
-    endif
-
-    execute
-    \   printf('function! %s( ArgLead, CmdLine, CursorPos )', l:funcName) . "\n" .
-    \   printf('    return filter(%s, ''v:val =~ "\\V\\^" . escape(a:ArgLead, "\\")'')', a:argumentExpr) . "\n" .
-    \          'endfunction'
-
-    return l:funcName
+    return call('ingo#plugin#cmdcomplete#MakeCompleteFunc',
+    \   [printf('return filter(%s, ''v:val =~ "\\V\\^" . escape(a:ArgLead, "\\")'')', a:argumentExpr)] +
+    \   a:000
+    \)
 endfunction
 
 let &cpo = s:save_cpo
diff --git a/doc/ingo-library.txt b/doc/ingo-library.txt
index cd4c253..72ecd73 100644
--- a/doc/ingo-library.txt
+++ b/doc/ingo-library.txt
@@ -107,6 +107,7 @@ HISTORY							*ingo-library-history*
 - Add ingo/lists/find.vim module.
 - Add ingo/folds/containment.vim module.
 - Add ingo/ftplugin/setting.vim module.
+- Extract generic ingo#plugin#cmdcomplete#MakeCompleteFunc().
 
 1.034	13-Feb-2018
 - Add ingo/regexp/split.vim module.