Progress bar: Add a key to show what paths remain to be built/substituted

src/libmain/progress-bar.cc

@@ -69,6 +69,7 @@ private:
         ActivityId parent;
         std::optional<std::string> name;
         std::optional<std::chrono::time_point<std::chrono::steady_clock>> startTime;
+        PathSet buildsRemaining, substitutionsRemaining;
     };
 
     struct ActivitiesByType
@@ -250,16 +251,49 @@ public:
                             resetHelp(*state);
                         } else {
                             state->helpShown = true;
-                            state->statusLines.insert_or_assign({idHelp, 0}, "");
-                            state->statusLines.insert_or_assign({idHelp, 1}, ANSI_BOLD "The following keys are available:");
-                            state->statusLines.insert_or_assign({idHelp, 2}, ANSI_BOLD "  'v' to increase verbosity.");
-                            state->statusLines.insert_or_assign({idHelp, 3}, ANSI_BOLD "  '-' to decrease verbosity.");
-                            state->statusLines.insert_or_assign({idHelp, 4}, ANSI_BOLD "  'l' to show build log output.");
-                            state->statusLines.insert_or_assign({idHelp, 5}, ANSI_BOLD "  'q' to quit.");
-                            state->statusLines.insert_or_assign({idHelp, 6}, "");
+                            size_t n = 0;
+                            state->statusLines.insert_or_assign({idHelp, n++}, "");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "The following keys are available:");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  'v' to increase verbosity.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  '-' to decrease verbosity.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  'l' to show build log output.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  'r' to show what paths remain to be built/substituted.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  'h' to hide this help message.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, ANSI_BOLD "  'q' to quit.");
+                            state->statusLines.insert_or_assign({idHelp, n++}, "");
                         }
                         draw(*state);
                     }
+                    if (c == 'r') {
+                        auto state(state_.lock());
+
+                        PathSet buildsRemaining, substitutionsRemaining;
+                        for (auto & act : state->activities) {
+                            for (auto & path : act.buildsRemaining) buildsRemaining.insert(path);
+                            for (auto & path : act.substitutionsRemaining) substitutionsRemaining.insert(path);
+                        }
+
+                        std::string msg;
+
+                        // FIXME: sort by name?
+
+                        if (!buildsRemaining.empty()) {
+                            msg += fmt("\n" ANSI_BOLD "%d derivations remaining to be built:\n" ANSI_NORMAL, buildsRemaining.size());
+                            for (auto & path : buildsRemaining)
+                                msg += fmt("  • %s\n", path);
+                        }
+
+                        if (!substitutionsRemaining.empty()) {
+                            msg += fmt("\n" ANSI_BOLD "%d paths remaining to be substituted:\n" ANSI_NORMAL, substitutionsRemaining.size());
+                            for (auto & path : substitutionsRemaining)
+                                msg += fmt("  • %s\n", path);
+                        }
+
+                        if (buildsRemaining.empty() && substitutionsRemaining.empty())
+                            msg = "\n" ANSI_BOLD "Nothing left to be built or substituted.";
+
+                        draw(*state, chomp(msg));
+                    }
                 }
             });
 
@@ -460,6 +494,10 @@ public:
     {
         auto state(state_.lock());
 
+        auto i = state->its.find(act);
+        assert(i != state->its.end());
+        ActInfo & actInfo = *i->second;
+
         if (type == resFileLinked) {
             state->filesLinked++;
             state->bytesLinked += getI(fields, 0);
@@ -469,8 +507,6 @@ public:
         else if (type == resBuildLogLine || type == resPostBuildLogLine) {
             auto lastLine = chomp(getS(fields, 0));
             if (!lastLine.empty()) {
-                auto i = state->its.find(act);
-                assert(i != state->its.end());
                 i->second->lastLine = lastLine;
                 if (progressBarSettings.printBuildLogs) {
                     auto suffix = "> ";
@@ -494,16 +530,11 @@ public:
         }
 
         else if (type == resSetPhase) {
-            auto i = state->its.find(act);
-            assert(i != state->its.end());
             i->second->phase = getS(fields, 0);
             update(*state);
         }
 
         else if (type == resProgress) {
-            auto i = state->its.find(act);
-            assert(i != state->its.end());
-            ActInfo & actInfo = *i->second;
             if (!actInfo.ignored) {
                 actInfo.done = getI(fields, 0);
                 actInfo.expected = getI(fields, 1);
@@ -514,9 +545,6 @@ public:
         }
 
         else if (type == resSetExpected) {
-            auto i = state->its.find(act);
-            assert(i != state->its.end());
-            ActInfo & actInfo = *i->second;
             if (!actInfo.ignored) {
                 auto type = (ActivityType) getI(fields, 0);
                 auto & j = actInfo.expectedByType[type];
@@ -526,6 +554,18 @@ public:
                 update(*state);
             }
         }
+
+        else if (type == resExpectBuild)
+            actInfo.buildsRemaining.insert(getS(fields, 0));
+
+        else if (type == resUnexpectBuild)
+            actInfo.buildsRemaining.erase(getS(fields, 0));
+
+        else if (type == resExpectSubstitution)
+            actInfo.substitutionsRemaining.insert(getS(fields, 0));
+
+        else if (type == resUnexpectSubstitution)
+            actInfo.substitutionsRemaining.erase(getS(fields, 0));
     }
 
     void update(State & state)

src/libstore/build/worker.cc

@@ -103,12 +103,16 @@ static void removeGoal(std::shared_ptr<G> goal, std::map<StorePath, std::weak_pt
 
 void Worker::removeGoal(GoalPtr goal)
 {
-    if (auto drvGoal = std::dynamic_pointer_cast<DerivationGoal>(goal))
+    if (auto drvGoal = std::dynamic_pointer_cast<DerivationGoal>(goal)) {
+        act.result(resUnexpectBuild, store.printStorePath(drvGoal->drvPath));
         nix::removeGoal(drvGoal, derivationGoals);
-    else if (auto subGoal = std::dynamic_pointer_cast<SubstitutionGoal>(goal))
+    }
+    else if (auto subGoal = std::dynamic_pointer_cast<SubstitutionGoal>(goal)) {
+        act.result(resUnexpectSubstitution, store.printStorePath(subGoal->storePath));
         nix::removeGoal(subGoal, substitutionGoals);
-    else
+    } else
         assert(false);
+
     if (topGoals.find(goal) != topGoals.end()) {
         topGoals.erase(goal);
         /* If a top-level goal failed, then kill all other goals
@@ -223,6 +227,12 @@ void Worker::run(const Goals & _topGoals)
     uint64_t downloadSize, narSize;
     store.queryMissing(topPaths, willBuild, willSubstitute, unknown, downloadSize, narSize);
 
+    for (auto & path : willBuild)
+        act.result(resExpectBuild, store.printStorePath(path));
+
+    for (auto & path : willSubstitute)
+        act.result(resExpectSubstitution, store.printStorePath(path));
+
     debug("entered goal loop");
 
     while (1) {

src/libutil/logging.hh

@@ -32,6 +32,10 @@ typedef enum {
     resProgress = 105,
     resSetExpected = 106,
     resPostBuildLogLine = 107,
+    resExpectBuild = 108,
+    resUnexpectBuild = 109,
+    resExpectSubstitution = 110,
+    resUnexpectSubstitution = 111,
 } ResultType;
 
 typedef uint64_t ActivityId;