From 6ce565163cf811381af60029ae3e5d44f3787ae6 Mon Sep 17 00:00:00 2001
From: Sameer Rahmani <lxsameer@gnu.org>
Date: Thu, 29 Apr 2021 23:39:58 +0100
Subject: [PATCH] Add support for current namespace in the context

---
 include/serene/context.h        | 11 +++++++++++
 src/serene/context.cpp          | 19 +++++++++++++++++++
 src/serene/exprs/def.cpp        |  7 +++++++
 src/tests/context_tests.cpp.inc | 12 ++++++++++++
 4 files changed, 49 insertions(+)

diff --git a/include/serene/context.h b/include/serene/context.h
index 27ae48f..18ec914 100644
--- a/include/serene/context.h
+++ b/include/serene/context.h
@@ -39,12 +39,23 @@ using Node = std::shared_ptr<Expression>;
 class SereneContext {
   std::map<std::string, std::shared_ptr<Namespace>> namespaces;
 
+  // Why string vs pointer? We might rewrite the namespace and
+  // holding a pointer means that it might point to the old version
+  std::string current_ns;
+
 public:
   /// Insert the given `ns` into the context. The Context object is
   /// the owner of all the namespaces. The `ns` will overwrite any
   /// namespace with the same name.
   void insertNS(std::shared_ptr<Namespace> ns);
 
+  /// Sets the name of the current namespace in the context and return
+  /// a boolean indicating the status of this operation. The operation
+  /// will fail if the namespace does not exist in the namespace table.
+  bool setCurrentNS(llvm::StringRef ns_name);
+
+  std::shared_ptr<Namespace> getCurrentNS();
+
   std::shared_ptr<Namespace> getNS(llvm::StringRef ns_name);
   SereneContext(){};
 };
diff --git a/src/serene/context.cpp b/src/serene/context.cpp
index c1a1c2f..8fd6c78 100644
--- a/src/serene/context.cpp
+++ b/src/serene/context.cpp
@@ -39,5 +39,24 @@ std::shared_ptr<Namespace> SereneContext::getNS(llvm::StringRef ns_name) {
   return nullptr;
 };
 
+bool SereneContext::setCurrentNS(llvm::StringRef ns_name) {
+  if (namespaces.count(ns_name.str())) {
+    this->current_ns = ns_name;
+    return true;
+  }
+
+  return false;
+};
+
+std::shared_ptr<Namespace> SereneContext::getCurrentNS() {
+  assert(!this->current_ns.empty() && "Current namespace is not set");
+
+  if (namespaces.count(this->current_ns)) {
+    return namespaces[this->current_ns];
+  }
+
+  return nullptr;
+};
+
 SereneContext makeSereneContext() { return SereneContext(); };
 }; // namespace serene
diff --git a/src/serene/exprs/def.cpp b/src/serene/exprs/def.cpp
index ecfba68..3b6d0df 100644
--- a/src/serene/exprs/def.cpp
+++ b/src/serene/exprs/def.cpp
@@ -87,8 +87,15 @@ MaybeNode Def::make(SereneContext &ctx, List *list) {
     return value;
   }
 
+  // auto result = ctx.getCurrentNS()->semanticEnv.insert_symbol(binding->name,
+  // analyzedValue);
+
+  // if (result.succeeded()) {
   Node def = exprs::make<Def>(list->location, binding->name, analyzedValue);
   return Result<Node>::success(def);
+  // } else {
+  //   return Result<Node>::error()
+  // }
 };
 } // namespace exprs
 } // namespace serene
diff --git a/src/tests/context_tests.cpp.inc b/src/tests/context_tests.cpp.inc
index 5b004f6..1dd1b50 100644
--- a/src/tests/context_tests.cpp.inc
+++ b/src/tests/context_tests.cpp.inc
@@ -59,5 +59,17 @@ TEST_CASE("Context tests", "[context]") {
 
 };
 
+TEST_CASE("Get and Set current namespace", "[context]") {
+  auto ctx = makeSereneContext();
+  auto userNs = makeNamespace(ctx, "user", llvm::Optional<llvm::StringRef>("/some/file"));
 
+  auto isSet = ctx.setCurrentNS("user");
+
+  REQUIRE(isSet);
+  CHECK(ctx.getCurrentNS() == userNs);
+
+  isSet = ctx.setCurrentNS("user1");
+  REQUIRE_FALSE(isSet);
+  CHECK(ctx.getCurrentNS() == userNs);
+};
 } // namespace serene