Add lua argument checker

automation/include/aegisub/argcheck.moon

@@ -0,0 +1,78 @@
+-- Copyright (c) 2014, Thomas Goyne <plorkyeran@aegisub.org>
+--
+-- Permission to use, copy, modify, and distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+-- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+-- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+-- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+--
+-- Aegisub Project http://www.aegisub.org/
+
+assert   = assert
+error    = error
+select   = select
+tostring = tostring
+type     = type
+
+is_type = (v, ty, expected) ->
+  ty == expected or (ty == 'table' and v.__class and v.__class.__name == expected)
+
+(argfmt) ->
+  assert type(argfmt) == 'string'
+  min_args = 0
+  max_args = 0
+  checks = {}
+  for arg in argfmt\gmatch '[^ ]+'
+    if arg == '...'
+      max_args = nil
+      break
+
+    max_args += 1
+
+    optional = arg\sub(1, 1) == '?'
+    if optional
+      arg = arg\sub 2
+    else
+      min_args += 1
+
+    if arg\find '|'
+      types = [ty for ty in arg\gmatch '[^|]+']
+      checks[max_args] = (i, v) ->
+        if v == nil
+          return if optional
+          error "Argument ##{i} should be a #{arg}, is nil", 4
+        ty = type v
+        for argtype in *types
+          return if is_type v, ty, argtype
+        error "Argument ##{i} should be a #{arg}, is #{ty} (#{v})", 3
+    else
+      checks[max_args] = (i, v) ->
+        if v == nil
+          return if optional
+          error "Argument ##{i} should be a #{arg}, is nil", 4
+        ty = type v
+        return if is_type v, ty, arg
+        error "Argument ##{i} should be a #{arg}, is #{ty} (#{v})", 3
+
+  (fn) -> (...) ->
+    arg_count = select '#', ...
+    if arg_count < min_args or (max_args and arg_count > max_args)
+      if min_args == max_args
+        error "Expected #{min_args} arguments, got #{arg_count}", 3
+      else if max_args
+        error "Expected #{min_args}-#{max_args} arguments, got #{arg_count}", 3
+      else
+        error "Expected at least #{min_args} arguments, got #{arg_count}", 3
+
+    for i=1,arg_count
+      if not checks[i] then break
+      checks[i] i, select i, ...
+
+    fn ...
+

automation/include/aegisub/lfs.moon

@@ -15,6 +15,8 @@
 -- Aegisub Project http://www.aegisub.org/
 
 impl = require 'aegisub.__lfs_impl'
+
+check = require 'aegisub.argcheck'
 ffi = require 'ffi'
 ffi_util = require 'aegisub.ffi'
 
@@ -29,7 +31,7 @@ number_ret = (f) -> (...) ->
   res, err = f ...
   tonumber(res), err
 
-attributes = (path, field) ->
+attributes = check'string ?string' (path, field) ->
   switch field
     when 'mode'
       res, err = impl.get_mode path
@@ -62,7 +64,7 @@ class dir_iter
     if err then error err, 2
     ffi_util.string str
 
-dir = (path) ->
+dir = check'string' (path) ->
   obj, err = impl.dir_new path
   if err
     error 2, err
@@ -71,10 +73,10 @@ dir = (path) ->
 
 return {
   :attributes
-  chdir: number_ret impl.chdir
-  currentdir: string_ret impl.currentdir
+  chdir: check'string' number_ret impl.chdir
+  currentdir: check'' string_ret impl.currentdir
   :dir
-  mkdir: number_ret impl.mkdir
-  rmdir: number_ret impl.rmdir
-  touch: number_ret impl.touch
+  mkdir: check'string' number_ret impl.mkdir
+  rmdir: check'string'number_ret impl.rmdir
+  touch: check'string'number_ret impl.touch
 }

automation/include/aegisub/re.moon

@@ -20,6 +20,7 @@ type   = type
 bit = require 'bit'
 ffi = require 'ffi'
 ffi_util = require 'aegisub.ffi'
+check = require 'aegisub.argcheck'
 
 ffi.cdef[[
   typedef struct agi_re_flag {
@@ -91,12 +92,6 @@ unpack_args = (...) ->
   return 0, ... unless flags_start
   process_flags(select flags_start, ...), select_first flags_start - 1, ...
 
--- Typecheck a variable and throw an error if it fails
-check_arg = (arg, expected_type, argn, func_name, level) ->
-  if type(arg) != expected_type
-    error "Argument #{argn} to #{func_name} should be a '#{expected_type}', is '#{type(arg)}' (#{arg})",
-      level + 1
-
 -- Replace a match with the value returned from func when passed the match
 replace_match = (match, func, str, last, acc) ->
   -- Copy everything between the last match and this match
@@ -155,9 +150,7 @@ class RegEx
 
   new: (@_regex, @_level) =>
 
-  gsplit: (str, skip_empty, max_split) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'gsplit', @_level
+  gsplit: check'RegEx string ?boolean ?number' (str, skip_empty, max_split) =>
     if not max_split or max_split <= 0 then max_split = str\len()
 
     start = 0
@@ -187,15 +180,10 @@ class RegEx
 
     do_split
 
-  split: (str, skip_empty, max_split) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'split', @_level
+  split: check'RegEx string ?boolean ?number' (str, skip_empty, max_split) =>
     [v for v in @gsplit str, skip_empty, max_split]
 
-  gfind: (str) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'gfind', @_level
-
+  gfind: check'RegEx string' (str) =>
     start = 0
     ->
       first, last = search(@_regex, str, start)
@@ -204,31 +192,19 @@ class RegEx
       start = if last > start then last else start + 1
       str\sub(first, last), first, last
 
-  find: (str) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'find', @_level
-
+  find: check'RegEx string' (str) =>
     ret = [str: s, first: f, last: l for s, f, l in @gfind(str)]
     next(ret) and ret
 
-  sub: (str, repl, max_count) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'sub', @_level
-    if max_count != nil
-      check_arg max_count, 'number', 4, 'sub', @_level
-
+  sub: check'RegEx string string|function ?number' (str, repl, max_count) =>
     max_count = str\len() + 1 if not max_count or max_count == 0
 
     if type(repl) == 'function'
        do_replace_fun @, repl, str, max_count
     elseif type(repl) == 'string'
       replace @_regex, repl, str, max_count
-    else
-      error "Argument 2 to sub should be a string or function, is '#{type(repl)}' (#{repl})", @_level
 
-  gmatch: (str, start) =>
-    @_check_self!
-    check_arg str, 'string', 2, 'gmatch', @_level
+  gmatch: check'RegEx string ?number' (str, start) =>
     start = if start then start - 1 else 0
 
     m = match @_regex, str, start
@@ -245,10 +221,7 @@ class RegEx
         last: last + start
       }
 
-  match: (str, start) =>
-    @_check_self!
-    check_arg(str, 'string', 2, 'match', @_level)
-
+  match: check'RegEx string ?number' (str, start) =>
     ret = [v for v in @gmatch str, start]
     -- Return nil rather than a empty table so that if re.match(...) works
     return nil if next(ret) == nil
@@ -271,16 +244,13 @@ invoke = (str, pattern, fn, flags, ...) ->
   compiled_regex[fn](compiled_regex, str, ...)
 
 -- Generate a static version of a method with arg type checking
-gen_wrapper = (impl_name) -> (str, pattern, ...) ->
-  check_arg str, 'string', 1, impl_name, 2
-  check_arg pattern, 'string', 2, impl_name, 2
+gen_wrapper = (impl_name) -> check'string string ...' (str, pattern, ...) ->
   invoke str, pattern, impl_name, unpack_args ...
 
 -- And now at last the actual public API
 do
   re = {
-    compile: (pattern, ...) ->
-      check_arg pattern, 'string', 1, 'compile', 2
+    compile: check'string ...' (pattern, ...) ->
       real_compile pattern, 2, process_flags(...), 2
 
     split:  gen_wrapper 'split'

automation/include/aegisub/unicode.moon

@@ -29,11 +29,13 @@
 -- http://www.ietf.org/rfc/rfc2279.txt
 
 impl = require 'aegisub.__unicode_impl'
+
+check = require 'aegisub.argcheck'
 ffi = require 'ffi'
 ffi_util = require 'aegisub.ffi'
 
 err_buff = ffi.new 'char *[1]'
-conv_func = (f) -> (str) ->
+conv_func = (f) -> check'string' (str) ->
   err_buff[0] = nil
   result = f str, err_buff
   errmsg = ffi_util.string err_buff[0]
@@ -44,7 +46,7 @@ conv_func = (f) -> (str) ->
 local unicode
 unicode =
   -- Return the number of bytes occupied by the character starting at the i'th byte in s
-  charwidth: (s, i) ->
+  charwidth: check'string ?number' (s, i) ->
     b = s\byte i or 1
     -- FIXME, something in karaskel results in this case, shouldn't happen
     -- What would "proper" behaviour be? Zero? Or just explode?
@@ -55,7 +57,7 @@ unicode =
     else                4
 
   -- Returns an iterator function for iterating over the characters in s
-  chars: (s) ->
+  chars: check'string' (s) ->
     curchar, i = 0, 1
     ->
       return if i > s\len()
@@ -67,13 +69,13 @@ unicode =
 
   -- Returns the number of characters in s
   -- Runs in O(s:len()) time!
-  len: (s) ->
+  len: check'string' (s) ->
     n = 0
     n += 1 for c in unicode.chars s
     n
 
   -- Get codepoint of first char in s
-  codepoint: (s) ->
+  codepoint: check'string' (s) ->
     -- Basic case, ASCII
     b = s\byte 1
     return b if b < 128

automation/include/aegisub/util.moon

@@ -20,14 +20,16 @@ sformat  = string.format
 tonumber = tonumber
 type     = type
 
+check = require 'aegisub.argcheck'
+
 local *
 
 -- Make a shallow copy of a table
-copy = (tbl) -> {k, v for k, v in pairs tbl}
+copy = check'table' (tbl) -> {k, v for k, v in pairs tbl}
 
 -- Make a deep copy of a table
 -- Retains equality of table references inside the copy and handles self-referencing structures
-deep_copy = (tbl) ->
+deep_copy = check'table' (tbl) ->
   seen = {}
   copy = (val) ->
     return val if type(val) != 'table'
@@ -44,7 +46,7 @@ ass_alpha = (a) -> sformat "&H%02X&", a
 ass_style_color = (r, g, b, a) -> sformat "&H%02X%02X%02X%02X", a, b, g, r
 
 -- Extract colour components of an ASS colour
-extract_color = (s) ->
+extract_color = check'string' (s) ->
   local a, b, g, r
 
   -- Try a style first
@@ -68,10 +70,10 @@ extract_color = (s) ->
     return tonumber(r, 16), tonumber(g, 16) or 0, tonumber(b, 16) or 0, tonumber(a, 16) or 0
 
 -- Create an alpha override code from a style definition colour code
-alpha_from_style = (scolor) -> ass_alpha select 4, extract_color scolor
+alpha_from_style = check'string' (scolor) -> ass_alpha select 4, extract_color scolor
 
 -- Create an colour override code from a style definition colour code
-color_from_style = (scolor) ->
+color_from_style = check'string' (scolor) ->
   r, g, b = extract_color scolor
   ass_color r or 0, g or 0, b or 0
 

automation/tests/modules/argcheck.moon

@@ -0,0 +1,80 @@
+-- Copyright (c) 2014, Thomas Goyne <plorkyeran@aegisub.org>
+--
+-- Permission to use, copy, modify, and distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+-- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+-- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+-- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+--
+-- Aegisub Project http://www.aegisub.org/
+
+check = require 'aegisub.argcheck'
+
+describe 'argcheck', ->
+  it 'should permit simple valid calls', ->
+    assert.has_no.errors -> (check'string' ->) ''
+    assert.has_no.errors -> (check'number' ->) 10
+    assert.has_no.errors -> (check'boolean' ->) true
+    assert.has_no.errors -> (check'table' ->) {}
+
+  it 'should support multiple arguments', ->
+    assert.has_no.errors -> (check'string number' ->) '', 10
+    assert.has_no.errors -> (check'string table number' ->) '', {}, 10
+
+  it 'should support moonscript classes', ->
+    class Foo
+    assert.has_no.errors -> (check'Foo' (->) Foo)
+
+  it 'should support optional arguments', ->
+    assert.has_no.errors -> (check'?number' ->) nil
+    assert.has_no.errors -> (check'?number ?number' ->) 5
+
+  it 'should support ...', ->
+    assert.has_no.errors -> (check'number ...' ->) 5
+    assert.has_no.errors -> (check'number ...' ->) 5, 5
+    assert.has_no.errors -> (check'number ...' ->) 5, 5, ''
+
+  it 'should support alternates', ->
+    assert.has_no.errors -> (check'number|string' ->) 5
+    assert.has_no.errors -> (check'number|string' ->) ''
+
+  it 'should support optional alternates', ->
+    assert.has_no.errors -> (check'?number|string' ->) 5
+    assert.has_no.errors -> (check'?number|string' ->) ''
+    assert.has_no.errors -> (check'?number|string' ->) nil
+
+  it 'should reject simple invalid calls', ->
+    assert.has.errors -> (check'string' ->) 10
+    assert.has.errors -> (check'number' ->) ''
+
+  it 'should reject inccorect numbers of arguments', ->
+    assert.has.errors -> (check'string number' ->) ''
+    assert.has_no.errors -> (check'string ?number' ->) ''
+    assert.has.errors -> (check'string number' ->) '', 5, 5
+
+  it 'should reject non-optional nil arguments', ->
+    assert.has.errors -> (check'string number' ->) nil, nil
+
+  it 'should reject invalid matches with alternates', ->
+    assert.has.errors -> (check'number|string' ->) {}
+
+  it 'should report the correct error levels', ->
+    valid_err_loc = (fn) ->
+      _, err = pcall fn
+      err\find('tests/modules/argcheck.moon') != nil
+
+    assert.is.true valid_err_loc -> (check'number' ->) {}
+    assert.is.true valid_err_loc -> (check'number' ->) nil
+    assert.is.true valid_err_loc -> (check'number|string' ->) {}
+    assert.is.true valid_err_loc -> (check'number|string' ->) nil
+    assert.is.true valid_err_loc -> (check'number string' ->) {}
+    assert.is.true valid_err_loc -> (check'?number ?string' ->) 1, 2, 3
+    assert.is.true valid_err_loc -> (check'number string ...' ->) {}
+    prevent_tail_call_so_that_this_shows_up_in_backtrace = 1
+