Compound bugfix

spec/cli_spec.lua

@@ -300,8 +300,8 @@ Total: 5 warnings / 0 errors in 1 file
 
     spec/samples/compound_operators.lua:2:1: assignment uses compound operator +=
     spec/samples/compound_operators.lua:3:1: assignment uses compound operator -=
-    spec/samples/compound_operators.lua:4:1: assignment uses compound operator *=
-    spec/samples/compound_operators.lua:5:1: assignment uses compound operator /=
+    spec/samples/compound_operators.lua:5:2: assignment uses compound operator /=
+    spec/samples/compound_operators.lua:10:1: assignment uses compound operator *=
 
 Total: 0 warnings / 4 errors in 1 file
 ]], get_output "spec/samples/compound_operators.lua --no-config")
@@ -311,8 +311,8 @@ Total: 0 warnings / 4 errors in 1 file
       assert.equal([[Checking spec/samples/compound_operators.lua      3 errors
 
     spec/samples/compound_operators.lua:3:1: assignment uses compound operator -=
-    spec/samples/compound_operators.lua:4:1: assignment uses compound operator *=
-    spec/samples/compound_operators.lua:5:1: assignment uses compound operator /=
+    spec/samples/compound_operators.lua:5:2: assignment uses compound operator /=
+    spec/samples/compound_operators.lua:10:1: assignment uses compound operator *=
 
 Total: 0 warnings / 3 errors in 1 file
 ]], get_output "spec/samples/compound_operators.lua --no-config --operators +=")

spec/samples/compound_operators.lua

@@ -1,6 +1,11 @@
 local i = 0
 i += 10
 i -= 5
-i *= 2
-i /= 5
-return i
+local function func()
+	i /= 5
+end
+func()
+local t = {}
+t.a = i
+t.a *= 2
+return t

src/luacheck/parser.lua

@@ -931,7 +931,7 @@ local function parse_expression_statement(state)
          parse_error(state, "compound assignment not allowed on tuples near " .. compound_operator .. "=")
       end
 
-      return new_inner_node(start_range, rhs[1], "OpSet", {compound_operator, lhs[1], rhs[1]})
+      return new_inner_node(start_range, rhs[1], "OpSet", {lhs, rhs, compound_operator})
    else
       -- This is an assignment in the form `lhs = rhs`.
       check_and_skip_token(state, "=")

src/luacheck/stages/detect_compound_operators.lua

@@ -23,7 +23,7 @@ local reverse_compound_operators = {
 }
 
 local function check_node(chstate, node)
-    local operator = reverse_compound_operators[node[1]]
+    local operator = reverse_compound_operators[node[3]]
     chstate:warn_range("033", node, {operator = operator})
 end
 

src/luacheck/stages/detect_globals.lua

@@ -234,7 +234,7 @@ local function detect_globals_in_line(chstate, line)
          if item.rhs then
             detect_in_nodes(chstate, item, item.rhs, is_top_line)
          end
-      elseif item.tag == "Set" then
+      elseif item.tag == "Set" or item.tag == "OpSet" then
          detect_in_nodes(chstate, item, item.lhs, is_top_line, true)
          detect_in_nodes(chstate, item, item.rhs, is_top_line)
       end

src/luacheck/stages/linearize.lua

@@ -203,8 +203,8 @@ local function new_opset_item(node)
    return {
       tag = "OpSet",
       node = node,
-      lhs = node[2],
-      rhs = node[3],
+      lhs = node[1],
+      rhs = node[2],
       accesses = {},
       mutations = {},
       used_values = {},
@@ -530,18 +530,19 @@ end
 
 function LinState:emit_stmt_OpSet(node)
    local item = new_opset_item(node)
-   self:scan_expr(item, node[3])
+   self:scan_exprs(item, node[2])
 
-   local lhs = node[2]
-   if lhs.tag == "Id" then
-      local var = self:check_var(lhs)
+   for _, expr in ipairs(node[1]) do
+      if expr.tag == "Id" then
+         local var = self:check_var(expr)
 
-      if var then
-         self:register_upvalue_action(item, var, "set_upvalues")
+         if var then
+            self:register_upvalue_action(item, var, "set_upvalues")
+         end
+      else
+         assert(expr.tag == "Index")
+         self:scan_lhs_index(item, expr)
       end
-   else
-      assert(lhs.tag == "Index")
-      self:scan_lhs_index(item, lhs)
    end
 
    self:emit(item)
@@ -650,7 +651,7 @@ function LinState:register_set_variables()
    local line = self.lines.top
 
    for _, item in ipairs(line.items) do
-      if item.tag == "Local" or item.tag == "Set" then
+      if item.tag == "Local" or item.tag == "Set" or item.tag == "OpSet" then
          item.set_variables = {}
 
          local is_init = item.tag == "Local"
@@ -674,6 +675,10 @@ function LinState:register_set_variables()
             local value
 
             if node.var then
+               -- OpSet also accesses
+               if item.tag == "OpSet" then
+                  self:mark_access(item, node)
+               end
                value = new_value(node, item.rhs and item.rhs[i] or unpacking_item, item, is_init)
                item.set_variables[node.var] = value
                table.insert(node.var.values, value)

src/luacheck/stages/resolve_locals.lua

@@ -95,19 +95,24 @@ local function contains_call(node)
 end
 
 local function is_circular_reference(item, var)
+   -- OpSet is circular by definition
+   if not (item.tag == "Set" or item.tag == "Local") then
+      return false
+   end
+
    -- No support for matching multiple assignment to the specific assignment
-   if not (item.tag == "Set" or item.tag == "Local" or item.tag == "OpSet") then
+   if not item.lhs or #item.lhs ~= 1 or not item.rhs or #item.rhs ~= 1 then
       return false
    end
 
    -- Case t[t.function()] = t.func()
    -- Functions can have side-effects, so this isn't purely circular
-   local right_assignment = item.tag == "OpSet" and item.rhs or item.rhs[1]
+   local right_assignment = item.rhs[1]
    if contains_call(right_assignment) then
       return false
    end
 
-   local left_assignment = item.tag == "OpSet" and item.lhs or item.lhs[1]
+   local left_assignment = item.lhs[1]
    if contains_call(left_assignment) then
       return false
    end

src/luacheck/stages/unwrap_parens.lua

@@ -50,7 +50,7 @@ local function handle_nodes(chstate, nodes, list_start)
             if node[2] then
                handle_nodes(chstate, node[2])
             end
-         elseif tag == "Set" then
+         elseif tag == "Set" or tag == "OpSet" then
             handle_nodes(chstate, node[1])
             handle_nodes(chstate, node[2], 1)
          else
@@ -67,7 +67,7 @@ local function handle_nodes(chstate, nodes, list_start)
 
             -- warn that not (x == y) can become x ~= y
             if tag == "Op" and node[1] == "not" and node[2].tag == "Op" and relational_operators[node[2][1]] then
-            chstate:warn_range("581", node, {
+               chstate:warn_range("581", node, {
                   operator = relational_operators[node[2][1]],
                   replacement_operator = replacements[node[2][1]]
                })