From 61e4f761c1adf3a03bf65f0491931438b9c71f80 Mon Sep 17 00:00:00 2001
From: bog <bog@gozmail.net>
Date: Sun, 15 Oct 2023 04:36:02 +0200
Subject: [PATCH] :sparkles: $IN and $OUT special variables.

---
 src/Interpreter.cpp   | 21 +++++++++++++++++++--
 tests/Interpreter.cpp | 16 +++++++++++++++-
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/src/Interpreter.cpp b/src/Interpreter.cpp
index c533cfa..c0904ad 100644
--- a/src/Interpreter.cpp
+++ b/src/Interpreter.cpp
@@ -143,8 +143,15 @@ namespace sn
       }
     else if (node->type() == NODE_VAR)
       {
-        auto var = *m_sym.get(node->repr());
-        return var.values;
+        if (auto var = m_sym.get(node->repr());
+            var)
+          {
+            return var->values;
+          }
+        else
+          {
+            throw run_error {"cannot find variable '" + node->repr() + "'"};
+          }
       }
     else if (node->type() == NODE_ARRAY)
       {
@@ -280,12 +287,16 @@ namespace sn
         auto block = *node->get(2);
 
         std::vector<std::string> target_values;
+        std::vector<std::string> target_values_verbatim;
 
         for (size_t i=0; i<target_node->size(); i++)
           {
             auto t = *target_node->get(i);
             auto values = get_value(t);
 
+            std::copy(std::begin(values), std::end(values),
+                      std::back_inserter(target_values_verbatim));
+
             std::transform(std::begin(values),
                            std::end(values),
                            std::back_inserter(target_values),
@@ -294,12 +305,16 @@ namespace sn
           }
 
         std::vector<std::string> dep_values;
+        std::vector<std::string> dep_values_verbatim;
 
         for (size_t i=0; i<deps->size(); i++)
           {
             auto d = *deps->get(i);
             auto values = get_value(d);
 
+            std::copy(std::begin(values), std::end(values),
+                      std::back_inserter(dep_values_verbatim));
+
             std::transform(std::begin(values), std::end(values),
                            std::back_inserter(dep_values),
                            std::bind(&Interpreter::format_path, this,
@@ -313,6 +328,8 @@ namespace sn
                 m_dependencies[target].push_back(dep);
               }
 
+            m_sym.declare("IN", dep_values_verbatim);
+            m_sym.declare("OUT", target_values_verbatim);
             m_scripts[target] = scripts(block);
           }
       } break;
diff --git a/tests/Interpreter.cpp b/tests/Interpreter.cpp
index 095adda..7f547d4 100644
--- a/tests/Interpreter.cpp
+++ b/tests/Interpreter.cpp
@@ -79,7 +79,7 @@ public:
 
   void test_contains(std::string const& str, std::vector<std::string> vec)
   {
-    INFO("'" << str << "' not found");
+    INFO("'" << str << "' not found, got '" << vec[0] << "'");
     REQUIRE(std::find(std::begin(vec), std::end(vec), str)
             != std::end(vec));
   }
@@ -319,3 +319,17 @@ TEST_CASE_METHOD(InterpreterTest, "Interpreter_replace_ext")
       test_contains("x.h y.h z.d w t.h", res);
     }
 }
+
+TEST_CASE_METHOD(InterpreterTest, "Interpreter_in_out")
+{
+  SECTION("on array")
+    {
+      std::stringstream ss;
+      ss << "x y z -> a b c {" << std::endl;
+      ss << "$IN $OUT" << std::endl;
+      ss << "}" << std::endl;
+
+      auto res = TEST_RUN(ss.str(), std::filesystem::path("a"));
+      test_contains("a b c x y z", res);
+    }
+}