lua: metatable dispatch (__index/__newindex/arith/cmp/__call/__len) +23 tests

lib/lua/test.sh

@@ -594,6 +594,71 @@ cat > "$TMPFILE" << 'EPOCHS'
 (epoch 770)
 (eval "(lua-eval-ast \"local t = {} local s = t s.x = 42 return t.x\")")
 
+;; ── Phase 4: metatables ────────────────────────────────────────
+;; setmetatable / getmetatable
+(epoch 800)
+(eval "(lua-eval-ast \"local t = {} local r = setmetatable(t, {}) if r == t then return 1 else return 0 end\")")
+(epoch 801)
+(eval "(lua-eval-ast \"local mt = {} local t = setmetatable({}, mt) if getmetatable(t) == mt then return 1 else return 0 end\")")
+
+;; type()
+(epoch 810)
+(eval "(lua-eval-ast \"return type(1)\")")
+(epoch 811)
+(eval "(lua-eval-ast \"return type(\\\"s\\\")\")")
+(epoch 812)
+(eval "(lua-eval-ast \"return type({})\")")
+(epoch 813)
+(eval "(lua-eval-ast \"return type(nil)\")")
+(epoch 814)
+(eval "(lua-eval-ast \"return type(true)\")")
+(epoch 815)
+(eval "(lua-eval-ast \"return type(function() end)\")")
+
+;; __index
+(epoch 820)
+(eval "(lua-eval-ast \"local base = {x = 10} local t = setmetatable({}, {__index = base}) return t.x\")")
+(epoch 821)
+(eval "(lua-eval-ast \"local base = {x = 10} local t = setmetatable({y = 20}, {__index = base}) return t.x + t.y\")")
+(epoch 822)
+(eval "(lua-eval-ast \"local t = setmetatable({}, {__index = function(tbl, k) return k .. \\\"!\\\" end}) return t.hi\")")
+
+;; __newindex
+(epoch 830)
+(eval "(lua-eval-ast \"local log = {} local t = setmetatable({}, {__newindex = function(tbl, k, v) log[1] = k end}) t.foo = 1 return log[1]\")")
+
+;; Arithmetic metamethods
+(epoch 840)
+(eval "(lua-eval-ast \"local mt = {__add = function(a, b) return 99 end} local x = setmetatable({}, mt) return x + 1\")")
+(epoch 841)
+(eval "(lua-eval-ast \"local mt = {__add = function(a, b) return a.v + b.v end} local x = setmetatable({v = 3}, mt) local y = setmetatable({v = 4}, mt) return x + y\")")
+(epoch 842)
+(eval "(lua-eval-ast \"local mt = {__sub = function(a, b) return 7 end, __mul = function(a, b) return 11 end} local t = setmetatable({}, mt) return t - t + (t * t)\")")
+(epoch 843)
+(eval "(lua-eval-ast \"local mt = {__unm = function(a) return 42 end} local t = setmetatable({}, mt) return -t\")")
+(epoch 844)
+(eval "(lua-eval-ast \"local mt = {__concat = function(a, b) return \\\"cat\\\" end} local t = setmetatable({}, mt) return t .. \\\"x\\\"\")")
+
+;; Comparison metamethods
+(epoch 850)
+(eval "(lua-eval-ast \"local mt = {__eq = function(a, b) return true end} local x = setmetatable({}, mt) local y = setmetatable({}, mt) if x == y then return 1 else return 0 end\")")
+(epoch 851)
+(eval "(lua-eval-ast \"local mt = {__lt = function(a, b) return true end} local x = setmetatable({}, mt) local y = setmetatable({}, mt) if x < y then return 1 else return 0 end\")")
+(epoch 852)
+(eval "(lua-eval-ast \"local mt = {__le = function(a, b) return true end} local x = setmetatable({}, mt) local y = setmetatable({}, mt) if x <= y then return 1 else return 0 end\")")
+
+;; __call
+(epoch 860)
+(eval "(lua-eval-ast \"local mt = {__call = function(t, x) return x + 100 end} local obj = setmetatable({}, mt) return obj(5)\")")
+
+;; __len
+(epoch 870)
+(eval "(lua-eval-ast \"local mt = {__len = function(t) return 99 end} local t = setmetatable({}, mt) return #t\")")
+
+;; Classic OO pattern
+(epoch 880)
+(eval "(lua-eval-ast \"local Animal = {} Animal.__index = Animal function Animal:new(name) local o = setmetatable({name = name}, self) return o end function Animal:getName() return self.name end local a = Animal:new(\\\"Rex\\\") return a:getName()\")")
+
 EPOCHS
 
 OUTPUT=$(timeout 60 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
@@ -899,6 +964,31 @@ check 760 "t[k]=v reads via t.foo"          '88'
 check 761 "t[concat]=v reads via t.xy"      '7'
 check 770 "reference semantics t=s"         '42'
 
+# ── Phase 4: metatables ───────────────────────────────────────
+check 800 "setmetatable returns t"          '1'
+check 801 "getmetatable roundtrip"          '1'
+check 810 "type(1)"                         '"number"'
+check 811 "type(string)"                    '"string"'
+check 812 "type({})"                        '"table"'
+check 813 "type(nil)"                       '"nil"'
+check 814 "type(true)"                      '"boolean"'
+check 815 "type(function)"                  '"function"'
+check 820 "__index table lookup"            '10'
+check 821 "__index chain + self"            '30'
+check 822 "__index as function"             '"hi!"'
+check 830 "__newindex fires"                '"foo"'
+check 840 "__add table+number"              '99'
+check 841 "__add two tables"                '7'
+check 842 "__sub + __mul chain"             '18'
+check 843 "__unm"                           '42'
+check 844 "__concat"                        '"cat"'
+check 850 "__eq"                            '1'
+check 851 "__lt"                            '1'
+check 852 "__le"                            '1'
+check 860 "__call"                          '105'
+check 870 "__len"                           '99'
+check 880 "OO pattern self:m()"             '"Rex"'
+
 TOTAL=$((PASS + FAIL))
 if [ $FAIL -eq 0 ]; then
   echo "ok $PASS/$TOTAL Lua-on-SX tests passed"