fix optimization case from issue #115.

3 files changed, 44 insertions, 16 deletions

diff --git a/spec/inputs/assign.yue b/spec/inputs/assign.yue
index 8c7848d..8ae5cac 100644
--- a/spec/inputs/assign.yue
+++ b/spec/inputs/assign.yue
@@ -85,4 +85,8 @@ do
 do
         {a} = :b = c.d = e = tab
 
+do
+        val = 123
+        a = b = c = val
+
 nil
diff --git a/spec/outputs/assign.lua b/spec/outputs/assign.lua
index e638c47..d939769 100644
--- a/spec/outputs/assign.lua
+++ b/spec/outputs/assign.lua
@@ -135,23 +135,22 @@ return _(function()
                 local d = 0
         end
         do
-                local a
-                local b
-                local c
-                local d
-                do
-                        local _tmp_0 = f()
-                        a = _tmp_0
-                        b = _tmp_0
-                        c = _tmp_0
-                        d = _tmp_0
-                end
+                local a = f()
+                local b = a
+                local c = a
+                local d = a
         end
         do
-                local a = tab[1]
-                local b = tab.b
-                c.d = tab
                 local e = tab
+                local a = e[1]
+                local b = e.b
+                c.d = e
+        end
+        do
+                local val = 123
+                local a = val
+                local b = val
+                local c = val
         end
         return nil
 end)
diff --git a/src/yuescript/yue_compiler.cpp b/src/yuescript/yue_compiler.cpp
index cf9f188..3e58305 100644
--- a/src/yuescript/yue_compiler.cpp
+++ b/src/yuescript/yue_compiler.cpp
@@ -60,7 +60,7 @@ namespace yue {
 
 typedef std::list<std::string> str_list;
 
-const std::string_view version = "0.15.16"sv;
+const std::string_view version = "0.15.17"sv;
 const std::string_view extension = "yue"sv;
 
 class YueCompilerImpl {
@@ -8161,7 +8161,32 @@ private:
                 if (auto simpleVal = simpleSingleValueFrom(value)) {
                         constVal = ast_is<const_value_t, Num_t>(simpleVal->value);
                 }
-                if (constVal || !singleVariableFrom(value, false).empty()) {
+                bool localVal = false;
+                if (auto var = singleVariableFrom(value, false); isLocal(var)) {
+                        localVal = true;
+                }
+                if (!constVal && !localVal) {
+                        for (auto exp : chainAssign->exprs.objects()) {
+                                std::string var = singleVariableFrom(exp, false);
+                                if (!var.empty()) {
+                                        str_list temp;
+                                        transformAssignment(assignmentFrom(static_cast<Exp_t*>(exp), value, exp), temp);
+                                        auto newChainAssign = x->new_ptr<ChainAssign_t>();
+                                        auto newAssign = x->new_ptr<Assign_t>();
+                                        newAssign->values.push_back(exp);
+                                        newChainAssign->assign.set(newAssign);
+                                        for (auto e : chainAssign->exprs.objects()) {
+                                                if (e != exp) {
+                                                        newChainAssign->exprs.push_back(e);
+                                                }
+                                        }
+                                        transformChainAssign(newChainAssign, temp);
+                                        out.push_back(join(temp));
+                                        return;
+                                }
+                        }
+                }
+                if (constVal || localVal) {
                         for (auto exp : chainAssign->exprs.objects()) {
                                 transformAssignment(assignmentFrom(static_cast<Exp_t*>(exp), value, exp), temp);
                         }