+ LuaMacro

1 files changed, 74 insertions, 0 deletions

diff --git a/Tools/LuaMacro/macro/assert.lua b/Tools/LuaMacro/macro/assert.lua
new file mode 100644
index 0000000..b25daaf
--- /dev/null
+++ b/Tools/LuaMacro/macro/assert.lua
@@ -0,0 +1,74 @@
+--- a simple testing framework.
+-- Defines a single statment macro assert_ which has the following syntax:
+--
+--  - assert_ val1 == val2
+--  - assert_ val1 > val2
+--  - assert_ val1 < val2
+--  - assert_ val1 matches val2 (using string matching)
+--  - assert_ val1 throws val2  (ditto, on exception string)
+--
+-- The `==` case has some special forms. If `val2` is `(v1,v2,..)` then
+-- it's assumed that the expression `val1` returns multiple values. `==` will
+-- also do value equality for plain tables.  If `val2` is a number given in
+-- %f format (such as 3.14) then it will match `vall` up to that specified
+-- number of digits.
+--
+--     assert_ {one=1,two=2} == {two=2,one=1}
+--     assert_ 'hello' matches '^hell'
+--     assert_ 2 > 1
+--     assert_ ('hello'):find 'll' == (3,4)
+--     assert_ a.x throws 'attempt to index global'
+-- @module macro.assert
+
+local M = require 'macro'
+local relop = {
+    ['=='] = 'eq',
+    ['<'] = 'lt',
+    ['>'] = 'gt'
+}
+
+local function numfmt (x)
+    local int,frac = x:match('(%d+)%.(%d+)')
+    if not frac then return nil end
+    return '%'..#x..'.'..#frac..'f', x
+end
+
+--- assert that two values match the desired relation.
+-- @macro assert_
+M.define('assert_',function(get,put)
+    local testx,tok = get:upto(function(t,v)
+        return relop[t] or (t == 'iden' and (v == 'matches' or v == 'throws'))
+    end)
+    local testy,eos = get:line()
+    local otesty = testy
+    testx = tostring(testx)
+    testy = tostring(testy)
+    local t,v,op = tok[1],tok[2]
+    if relop[t] then
+        op = relop[t]
+        if t == '==' then
+            if testy:match '^%(.+%)$' then
+                testx = 'T_.tuple('..testx..')'
+                testy = 'T_.tuple'..testy
+            elseif #otesty == 1 and otesty[1][1] == 'number' then
+                local num = otesty[1][2]
+                local fmt,num = numfmt(num)
+                if fmt then -- explicit floating-point literal
+                    testy = '"'..num..'"'
+                    testx = '("'..fmt..'"):format('..testx..')'
+                    op = 'match'
+                end
+            end
+        end
+    elseif v == 'matches' then
+        op = 'match'
+    elseif v == 'throws' then
+        op = 'match'
+        testx = 'T_.pcall_no(function() return '..testx..' end)'
+    end
+    return ('T_.assert_%s(%s,%s)%s'):format(op,testx,testy,tostring(eos))
+end)
+
+return function()
+    return "T_ = require 'macro.lib.test'"
+end