Replace LogFormat::barWithLogs with a setting

This will make it easier to add more settings to the progress bar.

src/libmain/loggers.cc

@@ -15,8 +15,6 @@ LogFormat parseLogFormat(const std::string & logFormatStr) {
         return LogFormat::internalJSON;
     else if (logFormatStr == "bar")
         return LogFormat::bar;
-    else if (logFormatStr == "bar-with-logs")
-        return LogFormat::barWithLogs;
     throw Error("option 'log-format' has an invalid value '%s'", logFormatStr);
 }
 
@@ -30,8 +28,6 @@ Logger * makeDefaultLogger() {
         return makeJSONLogger(*makeSimpleLogger(true));
     case LogFormat::bar:
         return makeProgressBar();
-    case LogFormat::barWithLogs:
-        return makeProgressBar(true);
     default:
         abort();
     }

src/libmain/loggers.hh

@@ -9,7 +9,6 @@ enum class LogFormat {
   rawWithLogs,
   internalJSON,
   bar,
-  barWithLogs,
 };
 
 void setLogFormat(const std::string & logFormatStr);

src/libmain/progress-bar.cc

@@ -15,6 +15,10 @@
 
 namespace nix {
 
+ProgressBarSettings progressBarSettings;
+
+static GlobalConfig::Register rProgressBarSettings(&progressBarSettings);
+
 static std::string getS(const std::vector<Logger::Field> & fields, size_t n)
 {
     assert(n < fields.size());
@@ -133,8 +137,6 @@ private:
         bool active = true;
         bool haveUpdate = true;
 
-        bool printBuildLogs;
-
         std::map<LineId, std::string> statusLines;
 
         /* How many lines need to be erased when redrawing. */
@@ -158,9 +160,9 @@ private:
 
 public:
 
-    ProgressBar(bool printBuildLogs, bool isTTY)
+    ProgressBar(bool isTTY)
         : isTTY(isTTY)
-        , state_({ .active = isTTY, .printBuildLogs = printBuildLogs })
+        , state_({ .active = isTTY })
     {
         state_.lock()->active = isTTY;
 
@@ -224,10 +226,10 @@ public:
                     }
                     if (c == 'l') {
                         auto state(state_.lock());
-                        state->printBuildLogs = !state->printBuildLogs;
+                        progressBarSettings.printBuildLogs = !progressBarSettings.printBuildLogs;
                         updateStatusLine(*state);
                         draw(*state,
-                            state->printBuildLogs
+                            progressBarSettings.printBuildLogs
                             ? ANSI_BOLD "Enabling build logs."
                             : ANSI_BOLD "Disabling build logs.");
                     }
@@ -298,7 +300,7 @@ public:
 
     bool isVerbose() override
     {
-        return state_.lock()->printBuildLogs;
+        return progressBarSettings.printBuildLogs;
     }
 
     void log(Verbosity lvl, const FormatOrString & fs) override
@@ -470,7 +472,7 @@ public:
                 auto i = state->its.find(act);
                 assert(i != state->its.end());
                 i->second->lastLine = lastLine;
-                if (state->printBuildLogs) {
+                if (progressBarSettings.printBuildLogs) {
                     auto suffix = "> ";
                     if (type == resPostBuildLogLine) {
                         suffix = " (post)> ";
@@ -720,10 +722,9 @@ public:
     }
 };
 
-Logger * makeProgressBar(bool printBuildLogs)
+Logger * makeProgressBar()
 {
     return new ProgressBar(
-        printBuildLogs,
         isatty(STDIN_FILENO)
         && isatty(STDOUT_FILENO)
         && isatty(STDERR_FILENO)
@@ -731,11 +732,6 @@ Logger * makeProgressBar(bool printBuildLogs)
     );
 }
 
-void startProgressBar(bool printBuildLogs)
-{
-    logger = makeProgressBar(printBuildLogs);
-}
-
 void stopProgressBar()
 {
     auto progressBar = dynamic_cast<ProgressBar *>(logger);

src/libmain/progress-bar.hh

@@ -4,10 +4,16 @@
 
 namespace nix {
 
-Logger * makeProgressBar(bool printBuildLogs = false);
-
-void startProgressBar(bool printBuildLogs = false);
+Logger * makeProgressBar();
 
 void stopProgressBar();
 
+struct ProgressBarSettings : Config
+{
+    Setting<bool> printBuildLogs{this, false, "print-build-logs",
+        "Whether the progress bar should print full build logs or just the most recent line."};
+};
+
+extern ProgressBarSettings progressBarSettings;
+
 }

src/nix-prefetch-url/nix-prefetch-url.cc

@@ -10,6 +10,7 @@
 #include "../nix/legacy.hh"
 #include "progress-bar.hh"
 #include "tarfile.hh"
+#include "loggers.hh"
 
 #include <iostream>
 
@@ -103,7 +104,7 @@ static int main_nix_prefetch_url(int argc, char * * argv)
         Finally f([]() { stopProgressBar(); });
 
         if (isatty(STDERR_FILENO))
-          startProgressBar();
+            setLogFormat(LogFormat::bar);
 
         auto store = openStore();
         auto state = std::make_unique<EvalState>(myArgs.searchPath, store);

src/nix/main.cc

@@ -10,6 +10,7 @@
 #include "filetransfer.hh"
 #include "finally.hh"
 #include "loggers.hh"
+#include "progress-bar.hh"
 
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -55,7 +56,6 @@ std::string programPath;
 
 struct NixArgs : virtual MultiCommand, virtual MixCommonArgs
 {
-    bool printBuildLogs = false;
     bool useNet = true;
     bool refresh = false;
 
@@ -88,12 +88,11 @@ struct NixArgs : virtual MultiCommand, virtual MixCommonArgs
             }},
         });
 
-        // FIXME: make this a setting, remove LogFormat::barWithLogs.
         addFlag({
             .longName = "print-build-logs",
             .shortName = 'L',
             .description = "print full build logs on stderr",
-            .handler = {[&]() { printBuildLogs = true; }},
+            .handler = {[&]() { progressBarSettings.printBuildLogs = true; }},
         });
 
         addFlag({
@@ -298,7 +297,7 @@ void mainWrapped(int argc, char * * argv)
 
     if (completions) return;
 
-    setLogFormat(args.printBuildLogs ? LogFormat::bar : LogFormat::barWithLogs);
+    setLogFormat(LogFormat::bar);
 
     Finally f([] { logger->stop(); });