nixd/attrs-eval: check value is in valid state (#423)

nix-community · Apr 16, 2024 · c280691 · c280691
1 parent 4ba76d8
commit c280691
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Showing 3 changed files with 56 additions and 6 deletions.
diff --git a/nixd/include/nixd/Eval/AttrSetProvider.h b/nixd/include/nixd/Eval/AttrSetProvider.h
@@ -32,14 +32,28 @@ class AttrSetProvider : public lspserver::LSPServer {
 
   std::unique_ptr<nix::EvalState> State;
 
-  nix::Value Nixpkgs;
+  nix::Value Val;
+
+  // If this value is valid
+  bool ValueValid = false;
 
   /// Convenient method for get state. Basically assume this->State is not null
   nix::EvalState &state() {
     assert(State && "State should be allocated by ctor!");
     return *State;
   }
 
+  /// \brief Check if the value is valid. \throw an exception if it is not.
+  void checkValueValid() const {
+    if (!ValueValid)
+      throw std::runtime_error("value is invalid");
+  }
+
+  nix::Value &validValue() {
+    checkValueValid();
+    return Val;
+  }
+
 public:
   AttrSetProvider(std::unique_ptr<lspserver::InboundPort> In,
                   std::unique_ptr<lspserver::OutboundPort> Out);

diff --git a/nixd/lib/Eval/AttrSetProvider.cpp b/nixd/lib/Eval/AttrSetProvider.cpp
@@ -126,9 +126,11 @@ void AttrSetProvider::onEvalExpr(
     const std::string &Name,
     lspserver::Callback<std::optional<std::string>> Reply) {
   try {
+    ValueValid = false;
     nix::Expr *AST = state().parseExprFromString(
         Name, state().rootPath(nix::CanonPath::fromCwd()));
-    state().eval(AST, Nixpkgs);
+    state().eval(AST, Val);
+    ValueValid = true;
     Reply(std::nullopt);
     return;
   } catch (const nix::BaseError &Err) {
@@ -149,7 +151,7 @@ void AttrSetProvider::onAttrPathInfo(
       return;
     }
 
-    nix::Value &Package = nixt::selectStrings(state(), Nixpkgs, AttrPath);
+    nix::Value &Package = nixt::selectStrings(state(), validValue(), AttrPath);
 
     AttrPathInfoResponse R;
     fillPackageDescription(state(), Package, R);
@@ -169,7 +171,8 @@ void AttrSetProvider::onAttrPathComplete(
     const AttrPathCompleteParams &Params,
     lspserver::Callback<AttrPathCompleteResponse> Reply) {
   try {
-    nix::Value &Scope = nixt::selectStrings(state(), Nixpkgs, Params.Scope);
+    nix::Value &Scope =
+        nixt::selectStrings(state(), validValue(), Params.Scope);
 
     state().forceValue(Scope, nix::noPos);
 
@@ -217,7 +220,7 @@ void AttrSetProvider::onOptionInfo(
       return;
     }
 
-    nix::Value &Option = nixt::selectStrings(state(), Nixpkgs, AttrPath);
+    nix::Value &Option = nixt::selectStrings(state(), validValue(), AttrPath);
 
     OptionInfoResponse R;
 
@@ -238,7 +241,8 @@ void AttrSetProvider::onOptionComplete(
     const AttrPathCompleteParams &Params,
     lspserver::Callback<OptionCompleteResponse> Reply) {
   try {
-    nix::Value &Scope = nixt::selectStrings(state(), Nixpkgs, Params.Scope);
+    nix::Value &Scope =
+        nixt::selectStrings(state(), validValue(), Params.Scope);
 
     state().forceValue(Scope, nix::noPos);
 

diff --git a/nixd/tools/nixd-attrset-eval/test/invalid-value.md b/nixd/tools/nixd-attrset-eval/test/invalid-value.md
@@ -0,0 +1,32 @@
+# RUN: nixd-attrset-eval --lit-test < %s | FileCheck %s
+
+
+```json
+{
+   "jsonrpc":"2.0",
+   "id":0,
+   "method":"attrset/evalExpr",
+   "params": "fuck $$@"
+}
+```
+
+
+```json
+{
+   "jsonrpc":"2.0",
+   "id":1,
+   "method":"attrset/attrpathInfo",
+   "params": [ "hello" ]
+}
+```
+
+```
+     CHECK:    "message": "value is invalid"
+CHECK-NEXT:  },
+CHECK-NEXT:  "id": 1,
+```
+
+```json
+{"jsonrpc":"2.0","method":"exit"}
+```
+