Merge branch 'master' into nix-repl-flakes

src/libcmd/command.cc

@@ -86,6 +86,11 @@ ref<Store> CopyCommand::getDstStore()
 
 EvalCommand::EvalCommand()
 {
+    addFlag({
+        .longName = "debugger",
+        .description = "start an interactive environment if evaluation fails",
+        .handler = {&startReplOnEvalErrors, true},
+    });
 }
 
 EvalCommand::~EvalCommand()
@@ -103,7 +108,7 @@ ref<Store> EvalCommand::getEvalStore()
 
 ref<EvalState> EvalCommand::getEvalState()
 {
-    if (!evalState)
+    if (!evalState) {
         evalState =
             #if HAVE_BOEHMGC
             std::allocate_shared<EvalState>(traceable_allocator<EvalState>(),
@@ -113,6 +118,11 @@ ref<EvalState> EvalCommand::getEvalState()
                 searchPath, getEvalStore(), getStore())
             #endif
             ;
+
+        if (startReplOnEvalErrors) {
+            evalState->debugRepl = &runRepl;        
+        };
+    }
     return ref<EvalState>(evalState);
 }
 

src/libcmd/command.hh

@@ -57,6 +57,8 @@ struct CopyCommand : virtual StoreCommand
 
 struct EvalCommand : virtual StoreCommand, MixEvalArgs
 {
+    bool startReplOnEvalErrors = false;
+
     EvalCommand();
 
     ~EvalCommand();
@@ -271,4 +273,8 @@ void printClosureDiff(
     const StorePath & afterPath,
     std::string_view indent);
 
+
+void runRepl(
+    ref<EvalState> evalState,
+    const ValMap & extraEnv);
 }

src/libcmd/installables.cc

@@ -623,7 +623,14 @@ std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableF
     std::set<std::string> outputsToInstall;
     std::optional<NixInt> priority;
 
-    if (auto aMeta = attr->maybeGetAttr(state->sMeta)) {
+    if (auto aOutputSpecified = attr->maybeGetAttr(state->sOutputSpecified)) {
+        if (aOutputSpecified->getBool()) {
+            if (auto aOutputName = attr->maybeGetAttr("outputName"))
+                outputsToInstall = { aOutputName->getString() };
+        }
+    }
+
+    else if (auto aMeta = attr->maybeGetAttr(state->sMeta)) {
         if (auto aOutputsToInstall = aMeta->maybeGetAttr("outputsToInstall"))
             for (auto & s : aOutputsToInstall->getListOfStrings())
                 outputsToInstall.insert(s);

src/libcmd/local.mk

@@ -6,9 +6,9 @@ libcmd_DIR := $(d)
 
 libcmd_SOURCES := $(wildcard $(d)/*.cc)
 
-libcmd_CXXFLAGS += -I src/libutil -I src/libstore -I src/libexpr -I src/libmain -I src/libfetchers
+libcmd_CXXFLAGS += -I src/libutil -I src/libstore -I src/libexpr -I src/libmain -I src/libfetchers -I src/nix
 
-libcmd_LDFLAGS += $(LOWDOWN_LIBS) -pthread
+libcmd_LDFLAGS = $(EDITLINE_LIBS) -llowdown -pthread
 
 libcmd_LIBS = libstore libutil libexpr libmain libfetchers