nixd/Sema: lowering for strings

nix-community · Sep 24, 2023 · 06f93ef · 06f93ef
1 parent 6e1270d
commit 06f93ef
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Showing 2 changed files with 31 additions and 0 deletions.
diff --git a/nixd/lib/Sema/Lowering.cpp b/nixd/lib/Sema/Lowering.cpp
@@ -615,6 +615,29 @@ nix::Expr *Lowering::lower(const syntax::Node *Root) {
     return Ctx.Pool.record(Ret);
   }
 
+  case Node::NK_String: {
+    const auto *String = dynamic_cast<const syntax::String *>(Root);
+    auto *NixString = new nix::ExprString(std::string(String->S));
+    return Ctx.Pool.record(NixString);
+  }
+
+  case Node::NK_ConcatStrings: {
+    const auto &CS = dynamic_cast<const syntax::ConcatStrings *>(Root);
+    nix::PosIdx P = CS->Range.Begin;
+    auto *ES = Ctx.ESPool.record(new EvalContext::ES);
+    for (Node *SubStr : CS->SubStrings) {
+      auto *NixSubStr = lower(SubStr);
+      ES->emplace_back(std::pair{SubStr->Range.Begin, NixSubStr});
+    }
+    auto *NixConcatStrings = new nix::ExprConcatStrings(P, CS->ForceString, ES);
+    return Ctx.Pool.record(NixConcatStrings);
+  }
+
+  case Node::NK_InterpExpr: {
+    const auto &IE = dynamic_cast<const syntax::InterpExpr *>(Root);
+    return lower(IE->Body);
+  }
+
   } // switch
 
   return nullptr;

diff --git a/nixd/tools/nixd-lint/test/lowering-string.nix b/nixd/tools/nixd-lint/test/lowering-string.nix
@@ -0,0 +1,8 @@
+# RUN: nixd-lint -dump-nix-ast %s | FileCheck %s
+{
+  # CHECK: ExprConcatStrings: (aa + "bbb" + cc)
+  s1 = "${aa}bbb${cc}";
+
+  # CHECK: ExprString: "aabbcc"
+  s2 = "aabbcc";
+}