5 files changed, 21 insertions, 12 deletions
diff --git a/src/libmain/common-args.cc b/src/libmain/common-args.cc
index 051668e53..09f4cd133 100644
--- a/src/libmain/common-args.cc
+++ b/src/libmain/common-args.cc
@@ -34,9 +34,19 @@ MixCommonArgs::MixCommonArgs(const string & programName)
             try {
                 globalConfig.set(name, value);
             } catch (UsageError & e) {
-                warn(e.what());
+                if (!completions)
+                    warn(e.what());
             }
         }},
+        .completer = [](size_t index, std::string_view prefix) {
+            if (index == 0) {
+                std::map<std::string, Config::SettingInfo> settings;
+                globalConfig.getSettings(settings);
+                for (auto & s : settings)
+                    if (hasPrefix(s.first, prefix))
+                        completions->insert(s.first);
+            }
+        }
     });
 
     addFlag({
diff --git a/src/libmain/loggers.cc b/src/libmain/loggers.cc
index c44bb6408..0a7291780 100644
--- a/src/libmain/loggers.cc
+++ b/src/libmain/loggers.cc
@@ -1,12 +1,13 @@
 #include "loggers.hh"
 #include "progress-bar.hh"
+#include "util.hh"
 
 namespace nix {
 
 LogFormat defaultLogFormat = LogFormat::raw;
 
 LogFormat parseLogFormat(const std::string & logFormatStr) {
-    if (logFormatStr == "raw")
+    if (logFormatStr == "raw" || getEnv("NIX_GET_COMPLETIONS"))
         return LogFormat::raw;
     else if (logFormatStr == "raw-with-logs")
         return LogFormat::rawWithLogs;
@@ -26,7 +27,7 @@ Logger * makeDefaultLogger() {
     case LogFormat::rawWithLogs:
         return makeSimpleLogger(true);
     case LogFormat::internalJson:
-        return makeJSONLogger(*makeSimpleLogger());
+        return makeJSONLogger(*makeSimpleLogger(true));
     case LogFormat::bar:
         return makeProgressBar();
     case LogFormat::barWithLogs:
diff --git a/src/libmain/progress-bar.cc b/src/libmain/progress-bar.cc
index 95a9187de..3f7d99a1d 100644
--- a/src/libmain/progress-bar.cc
+++ b/src/libmain/progress-bar.cc
@@ -131,7 +131,7 @@ public:
         auto state(state_.lock());
 
         std::stringstream oss;
-        oss << ei;
+        showErrorInfo(oss, ei, loggerSettings.showTrace.get());
 
         log(*state, ei.level, oss.str());
     }
diff --git a/src/libmain/shared.cc b/src/libmain/shared.cc
index 1cb422967..2b1f25ca3 100644
--- a/src/libmain/shared.cc
+++ b/src/libmain/shared.cc
@@ -36,7 +36,7 @@ void printGCWarning()
 
 void printMissing(ref<Store> store, const std::vector<StorePathWithOutputs> & paths, Verbosity lvl)
 {
-    unsigned long long downloadSize, narSize;
+    uint64_t downloadSize, narSize;
     StorePathSet willBuild, willSubstitute, unknown;
     store->queryMissing(paths, willBuild, willSubstitute, unknown, downloadSize, narSize);
     printMissing(store, willBuild, willSubstitute, unknown, downloadSize, narSize, lvl);
@@ -45,7 +45,7 @@ void printMissing(ref<Store> store, const std::vector<StorePathWithOutputs> & pa
 
 void printMissing(ref<Store> store, const StorePathSet & willBuild,
     const StorePathSet & willSubstitute, const StorePathSet & unknown,
-    unsigned long long downloadSize, unsigned long long narSize, Verbosity lvl)
+    uint64_t downloadSize, uint64_t narSize, Verbosity lvl)
 {
     if (!willBuild.empty()) {
         if (willBuild.size() == 1)
@@ -323,10 +323,8 @@ int handleExceptions(const string & programName, std::function<void()> fun)
         printError("Try '%1% --help' for more information.", programName);
         return 1;
     } catch (BaseError & e) {
-        if (settings.showTrace && e.prefix() != "")
-            printError(e.prefix());
         logError(e.info());
-        if (e.prefix() != "" && !settings.showTrace)
+        if (e.hasTrace() && !loggerSettings.showTrace.get())
             printError("(use '--show-trace' to show detailed location information)");
         return e.status;
     } catch (std::bad_alloc & e) {
@@ -386,7 +384,7 @@ RunPager::~RunPager()
 }
 
 
-string showBytes(unsigned long long bytes)
+string showBytes(uint64_t bytes)
 {
     return (format("%.2f MiB") % (bytes / (1024.0 * 1024.0))).str();
 }
diff --git a/src/libmain/shared.hh b/src/libmain/shared.hh
index f558247c0..ffae5d796 100644
--- a/src/libmain/shared.hh
+++ b/src/libmain/shared.hh
@@ -47,7 +47,7 @@ void printMissing(
 
 void printMissing(ref<Store> store, const StorePathSet & willBuild,
     const StorePathSet & willSubstitute, const StorePathSet & unknown,
-    unsigned long long downloadSize, unsigned long long narSize, Verbosity lvl = lvlInfo);
+    uint64_t downloadSize, uint64_t narSize, Verbosity lvl = lvlInfo);
 
 string getArg(const string & opt,
     Strings::iterator & i, const Strings::iterator & end);
@@ -110,7 +110,7 @@ extern volatile ::sig_atomic_t blockInt;
 
 /* GC helpers. */
 
-string showBytes(unsigned long long bytes);
+string showBytes(uint64_t bytes);
 
 struct GCResults;