infer by if not x or x.y then

Author: sumneko

script/vm/node.lua

@@ -10,6 +10,7 @@ vm.nodeCache = {}
 ---@field [integer] vm.object
 local mt = {}
 mt.__index    = mt
+mt.id         = 0
 mt.type       = 'vm.node'
 mt.optional   = nil
 mt.lastInfer  = nil
@@ -273,11 +274,16 @@ function vm.clearNodeCache()
     vm.nodeCache = {}
 end
 
+local ID = 0
+
 ---@param a? vm.node | vm.object
 ---@param b? vm.node | vm.object
 ---@return vm.node
 function vm.createNode(a, b)
-    local node = setmetatable({}, mt)
+    ID = ID + 1
+    local node = setmetatable({
+        id = ID,
+    }, mt)
     if a then
         node:merge(a)
     end

script/vm/runner.lua

@@ -72,35 +72,29 @@ function mt:_compileNarrowByFilter(filter, outStep, blockStep)
             self:_compileNarrowByFilter(filter[2], outStep, blockStep)
         end
         if filter.op.type == 'or' then
-            local orRightStep = {
+            local dummyStep = {
                 type  = 'load',
-                tag   = 'orRight',
+                tag   = 'dummy',
                 copy  = true,
                 ref1  = outStep,
                 pos   = filter.start - 1,
             }
-            local orLeftStep = {
+            self.steps[#self.steps+1] = dummyStep
+            self:_compileNarrowByFilter(filter[1], outStep, dummyStep)
+            dummyStep = {
                 type  = 'load',
-                tag   = 'orLeft',
+                tag   = 'dummy',
                 copy  = true,
                 ref1  = outStep,
-                pos   = filter.start - 1,
-            }
-            self.steps[#self.steps+1] = orRightStep
-            self.steps[#self.steps+1] = orLeftStep
-            self:_compileNarrowByFilter(filter[1], orRightStep, orLeftStep)
-            self.steps[#self.steps+1] = {
-                type  = 'load',
-                tag   = 'orReset',
-                ref1  = orRightStep,
-                pos   = filter.op.start
+                pos   = filter.op.finish,
             }
-            self:_compileNarrowByFilter(filter[2], orLeftStep, orRightStep)
+            self.steps[#self.steps+1] = dummyStep
+            self:_compileNarrowByFilter(filter[2], outStep, dummyStep)
             self.steps[#self.steps+1] = {
                 type  = 'load',
                 tag   = 'reset',
                 ref1  = blockStep,
-                pos   = filter.finish
+                pos   = filter.finish,
             }
         end
         if filter.op.type == '=='
@@ -339,11 +333,7 @@ function mt:launch(callback)
         elseif step.type == 'save' then
             step.node = node
         elseif step.type == 'load' then
-            if step.ref1 then
-                step.node = step.ref1.node
-            else
-                step.node = node
-            end
+            step.node = node
             context = step
         elseif step.type == 'merge' then
             node:merge(step.ref2.node)

test/type_inference/init.lua

@@ -1965,3 +1965,50 @@ local x
 if not x or <?x?> then
 end
 ]]
+
+TEST 'integer?' [[
+---@type integer?
+local x
+
+if not x or XXX then
+    print(<?x?>)
+end
+]]
+
+TEST 'integer?' [[
+---@type integer?
+local x
+
+if x or XXX then
+    print(<?x?>)
+end
+]]
+
+TEST 'integer?' [[
+---@type integer?
+local x
+
+if XXX or x then
+    print(<?x?>)
+end
+]]
+
+TEST 'integer?' [[
+---@type integer?
+local x
+
+if XXX or not x then
+    print(<?x?>)
+end
+]]
+
+TEST 'integer' [[
+---@type integer?
+local x
+
+if not x or XXX then
+    return
+end
+
+print(<?x?>)
+]]