lua/shared: move table util funcs to vim.shared

Use `tbl_` prefix for all table-util functions. Specify in the function
docstring if it expects a list-like or map-like table.

runtime/lua/vim/shared.lua

@@ -3,14 +3,27 @@
 --    - Can run in vanilla Lua (do not require a running instance of Nvim)
 
 
---- Merge map-like tables.
+-- Checks if a list-like (vector) table contains `value`.
+local function tbl_contains(t, value)
+  if type(t) ~= 'table' then
+    error('t must be a table')
+  end
+  for _,v in ipairs(t) do
+    if v == value then
+      return true
+    end
+  end
+  return false
+end
+
+--- Merges two or more map-like tables.
 --
 --@see |extend()|
 --
 -- behavior: Decides what to do if a key is found in more than one map:
 --           "error": raise an error
---           "keep":  skip
---           "force": set the item again
+--           "keep":  use value from the leftmost map
+--           "force": use value from the rightmost map
 local function tbl_extend(behavior, ...)
   if (behavior ~= 'error' and behavior ~= 'keep' and behavior ~= 'force') then
     error('invalid "behavior": '..tostring(behavior))
@@ -33,7 +46,28 @@ local function tbl_extend(behavior, ...)
   return ret
 end
 
+-- Flattens a list-like table: unrolls and appends nested tables to table `t`.
+local function tbl_flatten(t)
+  -- From https://github.com/premake/premake-core/blob/master/src/base/table.lua
+  local result = {}
+  local function _tbl_flatten(_t)
+    local n = #_t
+    for i = 1, n do
+      local v = _t[i]
+      if type(v) == "table" then
+        _tbl_flatten(v)
+      elseif v then
+        table.insert(result, v)
+      end
+    end
+  end
+  _tbl_flatten(t)
+  return result
+end
+
 local module = {
+  tbl_contains = tbl_contains,
   tbl_extend = tbl_extend,
+  tbl_flatten = tbl_flatten,
 }
 return module

test/functional/helpers.lua

@@ -15,7 +15,7 @@ local dedent = global_helpers.dedent
 local eq = global_helpers.eq
 local ok = global_helpers.ok
 local sleep = global_helpers.sleep
-local table_contains = global_helpers.table_contains
+local tbl_contains = global_helpers.tbl_contains
 local write_file = global_helpers.write_file
 
 local start_dir = lfs.currentdir()
@@ -165,7 +165,7 @@ local function expect_msg_seq(...)
         error(cat_err(final_error,
                       string.format('got %d messages (ignored %d), expected %d',
                                     #actual_seq, nr_ignored, #expected_seq)))
-      elseif table_contains(ignore, msg_type) then
+      elseif tbl_contains(ignore, msg_type) then
         nr_ignored = nr_ignored + 1
       else
         table.insert(actual_seq, msg)
@@ -339,9 +339,9 @@ local function remove_args(args, args_rm)
   end
   local last = ''
   for _, arg in ipairs(args) do
-    if table_contains(skip_following, last) then
+    if tbl_contains(skip_following, last) then
       last = ''
-    elseif table_contains(args_rm, arg) then
+    elseif tbl_contains(args_rm, arg) then
       last = arg
     else
       table.insert(new_args, arg)

test/functional/options/defaults_spec.lua

@@ -15,7 +15,7 @@ local neq = helpers.neq
 local mkdir = helpers.mkdir
 local rmdir = helpers.rmdir
 local alter_slashes = helpers.alter_slashes
-local table_contains = helpers.table_contains
+local tbl_contains = helpers.tbl_contains
 
 describe('startup defaults', function()
   describe(':filetype', function()
@@ -261,7 +261,7 @@ describe('XDG-based defaults', function()
 
     for _,v in ipairs(rtp) do
       local m = string.match(v, [=[[/\]nvim[^/\]*[/\]site.*$]=])
-      if m and not table_contains(rv, m) then
+      if m and not tbl_contains(rv, m) then
         table.insert(rv, m)
       end
     end

test/helpers.lua

@@ -612,37 +612,6 @@ local function fixtbl_rec(tbl)
   return fixtbl(tbl)
 end
 
--- From https://github.com/premake/premake-core/blob/master/src/base/table.lua
-local function table_flatten(arr)
-  local result = {}
-  local function _table_flatten(_arr)
-    local n = #_arr
-    for i = 1, n do
-      local v = _arr[i]
-      if type(v) == "table" then
-        _table_flatten(v)
-      elseif v then
-        table.insert(result, v)
-      end
-    end
-  end
-  _table_flatten(arr)
-  return result
-end
-
--- Checks if a list-like (vector) table contains `value`.
-local function table_contains(t, value)
-  if type(t) ~= 'table' then
-    error('t must be a table')
-  end
-  for _,v in ipairs(t) do
-    if v == value then
-      return true
-    end
-  end
-  return false
-end
-
 local function hexdump(str)
   local len = string.len(str)
   local dump = ""
@@ -787,15 +756,12 @@ local module = {
   repeated_read_cmd = repeated_read_cmd,
   shallowcopy = shallowcopy,
   sleep = sleep,
-  table_contains = table_contains,
-  tbl_extend = shared.tbl_extend,
-  table_flatten = table_flatten,
   tmpname = tmpname,
   uname = uname,
   updated = updated,
   which = which,
   write_file = write_file,
 }
-module = shared.tbl_extend('error', module, Paths)
+module = shared.tbl_extend('error', module, Paths, shared)
 
 return module