github.com/awirix/lua@v1.6.0/_lua5.1-tests/sort.lua (about)

     1  print"testing sort"
     2  
     3  
     4  function check (a, f)
     5    f = f or function (x,y) return x<y end;
     6    for n=table.getn(a),2,-1 do
     7      assert(not f(a[n], a[n-1]))
     8    end
     9  end
    10  
    11  a = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep",
    12       "Oct", "Nov", "Dec"}
    13  
    14  table.sort(a)
    15  check(a)
    16  
    17  limit = 30000
    18  if rawget(_G, "_soft") then limit = 5000 end
    19  
    20  a = {}
    21  for i=1,limit do
    22    a[i] = math.random()
    23  end
    24  
    25  local x = os.clock()
    26  table.sort(a)
    27  print(string.format("Sorting %d elements in %.2f sec.", limit, os.clock()-x))
    28  check(a)
    29  
    30  x = os.clock()
    31  table.sort(a)
    32  print(string.format("Re-sorting %d elements in %.2f sec.", limit, os.clock()-x))
    33  check(a)
    34  
    35  a = {}
    36  for i=1,limit do
    37    a[i] = math.random()
    38  end
    39  
    40  x = os.clock(); i=0
    41  table.sort(a, function(x,y) i=i+1; return y<x end)
    42  print(string.format("Invert-sorting other %d elements in %.2f sec., with %i comparisons",
    43        limit, os.clock()-x, i))
    44  check(a, function(x,y) return y<x end)
    45  
    46  
    47  table.sort{}  -- empty array
    48  
    49  for i=1,limit do a[i] = false end
    50  x = os.clock();
    51  table.sort(a, function(x,y) return nil end)
    52  print(string.format("Sorting %d equal elements in %.2f sec.", limit, os.clock()-x))
    53  check(a, function(x,y) return nil end)
    54  for i,v in pairs(a) do assert(not v or i=='n' and v==limit) end
    55  
    56  a = {"álo", "\0first :-)", "alo", "then this one", "45", "and a new"}
    57  table.sort(a)
    58  check(a)
    59  
    60  table.sort(a, function (x, y)
    61            -- loadstring(string.format("a[%q] = ''", x))()
    62            -- collectgarbage()
    63            return x<y
    64          end)
    65  
    66  
    67  tt = {__lt = function (a,b) return a.val < b.val end}
    68  a = {}
    69  for i=1,10 do  a[i] = {val=math.random(100)}; setmetatable(a[i], tt); end
    70  table.sort(a)
    71  check(a, tt.__lt)
    72  check(a)
    73  
    74  print"OK"