Merge remote-tracking branch 'origin/master' into flakes

28 files changed, 123 insertions, 103 deletions

diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index ec751ad31..31f8f5862 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -47,11 +47,10 @@ static void printValue(std::ostream & str, std::set<const Value *> & active, con
 {
     checkInterrupt();
 
-    if (active.find(&v) != active.end()) {
+    if (!active.insert(&v).second) {
         str << "<CYCLE>";
         return;
     }
-    active.insert(&v);
 
     switch (v.type) {
     case tInt:
@@ -1486,8 +1485,7 @@ void EvalState::forceValueDeep(Value & v)
     std::function<void(Value & v)> recurse;
 
     recurse = [&](Value & v) {
-        if (seen.find(&v) != seen.end()) return;
-        seen.insert(&v);
+        if (!seen.insert(&v).second) return;
 
         forceValue(v);
 
@@ -1905,8 +1903,7 @@ size_t valueSize(Value & v)
     std::set<const void *> seen;
 
     auto doString = [&](const char * s) -> size_t {
-        if (seen.find(s) != seen.end()) return 0;
-        seen.insert(s);
+        if (!seen.insert(s).second) return 0;
         return strlen(s) + 1;
     };
 
@@ -1914,8 +1911,7 @@ size_t valueSize(Value & v)
     std::function<size_t(Env & v)> doEnv;
 
     doValue = [&](Value & v) -> size_t {
-        if (seen.find(&v) != seen.end()) return 0;
-        seen.insert(&v);
+        if (!seen.insert(&v).second) return 0;
 
         size_t sz = sizeof(Value);
 
@@ -1930,8 +1926,7 @@ size_t valueSize(Value & v)
             sz += doString(v.path);
             break;
         case tAttrs:
-            if (seen.find(v.attrs) == seen.end()) {
-                seen.insert(v.attrs);
+            if (seen.insert(v.attrs).second) {
                 sz += sizeof(Bindings) + sizeof(Attr) * v.attrs->capacity();
                 for (auto & i : *v.attrs)
                     sz += doValue(*i.value);
@@ -1940,8 +1935,7 @@ size_t valueSize(Value & v)
         case tList1:
         case tList2:
         case tListN:
-            if (seen.find(v.listElems()) == seen.end()) {
-                seen.insert(v.listElems());
+            if (seen.insert(v.listElems()).second) {
                 sz += v.listSize() * sizeof(Value *);
                 for (size_t n = 0; n < v.listSize(); ++n)
                     sz += doValue(*v.listElems()[n]);
@@ -1962,8 +1956,7 @@ size_t valueSize(Value & v)
             sz += doValue(*v.primOpApp.right);
             break;
         case tExternal:
-            if (seen.find(v.external) != seen.end()) break;
-            seen.insert(v.external);
+            if (!seen.insert(v.external).second) break;
             sz += v.external->valueSize(seen);
             break;
         default:
@@ -1974,8 +1967,7 @@ size_t valueSize(Value & v)
     };
 
     doEnv = [&](Env & env) -> size_t {
-        if (seen.find(&env) != seen.end()) return 0;
-        seen.insert(&env);
+        if (!seen.insert(&env).second) return 0;
 
         size_t sz = sizeof(Env) + sizeof(Value *) * env.size;
 
diff --git a/src/libexpr/get-drvs.cc b/src/libexpr/get-drvs.cc
index 21a4d7917..4e22a1d77 100644
--- a/src/libexpr/get-drvs.cc
+++ b/src/libexpr/get-drvs.cc
@@ -277,8 +277,7 @@ static bool getDerivation(EvalState & state, Value & v,
 
         /* Remove spurious duplicates (e.g., a set like `rec { x =
            derivation {...}; y = x;}'. */
-        if (done.find(v.attrs) != done.end()) return false;
-        done.insert(v.attrs);
+        if (!done.insert(v.attrs).second) return false;
 
         DrvInfo drv(state, attrPath, v.attrs);
 
diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y
index 967c88d9b..93834bec6 100644
--- a/src/libexpr/parser.y
+++ b/src/libexpr/parser.y
@@ -1,5 +1,5 @@
 %glr-parser
-%pure-parser
+%define api.pure
 %locations
 %define parse.error verbose
 %defines
@@ -138,11 +138,10 @@ static void addAttr(ExprAttrs * attrs, AttrPath & attrPath,
 
 static void addFormal(const Pos & pos, Formals * formals, const Formal & formal)
 {
-    if (formals->argNames.find(formal.name) != formals->argNames.end())
+    if (!formals->argNames.insert(formal.name).second)
         throw ParseError(format("duplicate formal function argument '%1%' at %2%")
             % formal.name % pos);
     formals->formals.push_front(formal);
-    formals->argNames.insert(formal.name);
 }
 
 
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 32ce00bbc..7c3e5a4da 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -396,8 +396,7 @@ static void prim_genericClosure(EvalState & state, const Pos & pos, Value * * ar
             throw EvalError(format("attribute 'key' required, at %1%") % pos);
         state.forceValue(*key->value);
 
-        if (doneKeys.find(key->value) != doneKeys.end()) continue;
-        doneKeys.insert(key->value);
+        if (!doneKeys.insert(key->value).second) continue;
         res.push_back(e);
 
         /* Call the `operator' function with `e' as argument. */
@@ -1273,13 +1272,12 @@ static void prim_listToAttrs(EvalState & state, const Pos & pos, Value * * args,
         string name = state.forceStringNoCtx(*j->value, pos);
 
         Symbol sym = state.symbols.create(name);
-        if (seen.find(sym) == seen.end()) {
+        if (seen.insert(sym).second) {
             Bindings::iterator j2 = v2.attrs->find(state.symbols.create(state.sValue));
             if (j2 == v2.attrs->end())
                 throw TypeError(format("'value' attribute missing in a call to 'listToAttrs', at %1%") % pos);
 
             v.attrs->push_back(Attr(sym, j2->value, j2->pos));
-            seen.insert(sym);
         }
     }
 
diff --git a/src/libexpr/value-to-xml.cc b/src/libexpr/value-to-xml.cc
index 00b1918a8..1f0b1541d 100644
--- a/src/libexpr/value-to-xml.cc
+++ b/src/libexpr/value-to-xml.cc
@@ -105,10 +105,9 @@ static void printValueAsXML(EvalState & state, bool strict, bool location,
 
                 XMLOpenElement _(doc, "derivation", xmlAttrs);
 
-                if (drvPath != "" && drvsSeen.find(drvPath) == drvsSeen.end()) {
-                    drvsSeen.insert(drvPath);
+                if (drvPath != "" && drvsSeen.insert(drvPath).second)
                     showAttrs(state, strict, location, *v.attrs, doc, context, drvsSeen);
-                } else
+                else
                     doc.writeEmptyElement("repeated");
             }
 
diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index 53e357435..cdf848c98 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -568,10 +568,9 @@ UserLock::UserLock()
 
         {
             auto lockedPaths(lockedPaths_.lock());
-            if (lockedPaths->count(fnUserLock))
+            if (!lockedPaths->insert(fnUserLock).second)
                 /* We already have a lock on this one. */
                 continue;
-            lockedPaths->insert(fnUserLock);
         }
 
         try {
@@ -620,8 +619,8 @@ UserLock::UserLock()
 UserLock::~UserLock()
 {
     auto lockedPaths(lockedPaths_.lock());
-    assert(lockedPaths->count(fnUserLock));
-    lockedPaths->erase(fnUserLock);
+    auto erased = lockedPaths->erase(fnUserLock);
+    assert(erased);
 }
 
 
@@ -1125,10 +1124,8 @@ void DerivationGoal::addWantedOutputs(const StringSet & outputs)
         needRestart = true;
     } else
         for (auto & i : outputs)
-            if (wantedOutputs.find(i) == wantedOutputs.end()) {
-                wantedOutputs.insert(i);
+            if (wantedOutputs.insert(i).second)
                 needRestart = true;
-            }
 }
 
 
diff --git a/src/libstore/builtins/buildenv.cc b/src/libstore/builtins/buildenv.cc
index 74e706664..096593886 100644
--- a/src/libstore/builtins/buildenv.cc
+++ b/src/libstore/builtins/buildenv.cc
@@ -123,8 +123,7 @@ static Path out;
 
 static void addPkg(const Path & pkgDir, int priority)
 {
-    if (done.count(pkgDir)) return;
-    done.insert(pkgDir);
+    if (!done.insert(pkgDir).second) return;
     createLinks(pkgDir, out, priority);
 
     try {
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 307c00dbb..6bc3079a5 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -70,15 +70,17 @@ LocalStore::LocalStore(const Params & params)
         createSymlink(profilesDir, gcRootsDir + "/profiles");
     }
 
+    for (auto & perUserDir : {profilesDir + "/per-user", gcRootsDir + "/per-user"}) {
+        createDirs(perUserDir);
+        if (chmod(perUserDir.c_str(), 0755) == -1)
+            throw SysError("could not set permissions on '%s' to 755", perUserDir);
+    }
+
+    createUser(getUserName(), getuid());
+
     /* Optionally, create directories and set permissions for a
        multi-user install. */
     if (getuid() == 0 && settings.buildUsersGroup != "") {
-
-        Path perUserDir = profilesDir + "/per-user";
-        createDirs(perUserDir);
-        if (chmod(perUserDir.c_str(), 01777) == -1)
-            throw SysError(format("could not set permissions on '%1%' to 1777") % perUserDir);
-
         mode_t perm = 01775;
 
         struct group * gr = getgrnam(settings.buildUsersGroup.get().c_str());
@@ -1285,8 +1287,7 @@ void LocalStore::verifyPath(const Path & path, const PathSet & store,
 {
     checkInterrupt();
 
-    if (done.find(path) != done.end()) return;
-    done.insert(path);
+    if (!done.insert(path).second) return;
 
     if (!isStorePath(path)) {
         printError(format("path '%1%' is not in the Nix store") % path);
@@ -1426,4 +1427,19 @@ void LocalStore::signPathInfo(ValidPathInfo & info)
 }
 
 
+void LocalStore::createUser(const std::string & userName, uid_t userId)
+{
+    for (auto & dir : {
+        fmt("%s/profiles/per-user/%s", stateDir, userName),
+        fmt("%s/gcroots/per-user/%s", stateDir, userName)
+    }) {
+        createDirs(dir);
+        if (chmod(dir.c_str(), 0755) == -1)
+            throw SysError("changing permissions of directory '%s'", dir);
+        if (chown(dir.c_str(), userId, getgid()) == -1)
+            throw SysError("changing owner of directory '%s'", dir);
+    }
+}
+
+
 }
diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh
index 3ae34c403..379a06af8 100644
--- a/src/libstore/local-store.hh
+++ b/src/libstore/local-store.hh
@@ -293,6 +293,8 @@ private:
 
     Path getRealStoreDir() override { return realStoreDir; }
 
+    void createUser(const std::string & userName, uid_t userId) override;
+
     friend class DerivationGoal;
     friend class SubstitutionGoal;
 };
diff --git a/src/libstore/local.mk b/src/libstore/local.mk
index 89fc918c3..d690fea28 100644
--- a/src/libstore/local.mk
+++ b/src/libstore/local.mk
@@ -39,9 +39,12 @@ libstore_CXXFLAGS = \
  -DNIX_LIBEXEC_DIR=\"$(libexecdir)\" \
  -DNIX_BIN_DIR=\"$(bindir)\" \
  -DNIX_MAN_DIR=\"$(mandir)\" \
- -DSANDBOX_SHELL="\"$(sandbox_shell)\"" \
  -DLSOF=\"$(lsof)\"
 
+ifneq ($(sandbox_shell),)
+libstore_CXXFLAGS += -DSANDBOX_SHELL="\"$(sandbox_shell)\""
+endif
+
 $(d)/local-store.cc: $(d)/schema.sql.gen.hh
 
 $(d)/build.cc:
diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index dddf13430..05b93d4c9 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -29,8 +29,7 @@ void Store::computeFSClosure(const PathSet & startPaths,
         {
             auto state(state_.lock());
             if (state->exc) return;
-            if (state->paths.count(path)) return;
-            state->paths.insert(path);
+            if (!state->paths.insert(path).second) return;
             state->pending++;
         }
 
@@ -175,8 +174,7 @@ void Store::queryMissing(const PathSet & targets,
 
         {
             auto state(state_.lock());
-            if (state->done.count(path)) return;
-            state->done.insert(path);
+            if (!state->done.insert(path).second) return;
         }
 
         DrvPathWithOutputs i2 = parseDrvPathWithOutputs(path);
@@ -252,8 +250,7 @@ Paths Store::topoSortPaths(const PathSet & paths)
         if (parents.find(path) != parents.end())
             throw BuildError(format("cycle detected in the references of '%1%' from '%2%'") % path % *parent);
 
-        if (visited.find(path) != visited.end()) return;
-        visited.insert(path);
+        if (!visited.insert(path).second) return;
         parents.insert(path);
 
         PathSet references;
diff --git a/src/libstore/references.cc b/src/libstore/references.cc
index 5b7eb1f84..0dcc264c3 100644
--- a/src/libstore/references.cc
+++ b/src/libstore/references.cc
@@ -36,11 +36,10 @@ static void search(const unsigned char * s, size_t len,
             }
         if (!match) continue;
         string ref((const char *) s + i, refLength);
-        if (hashes.find(ref) != hashes.end()) {
+        if (hashes.erase(ref)) {
             debug(format("found reference to '%1%' at offset '%2%'")
                   % ref % i);
             seen.insert(ref);
-            hashes.erase(ref);
         }
         ++i;
     }
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index e8c1c1fdd..d0ef4e95b 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -949,8 +949,7 @@ std::list<ref<Store>> getDefaultSubstituters()
         StringSet done;
 
         auto addStore = [&](const std::string & uri) {
-            if (done.count(uri)) return;
-            done.insert(uri);
+            if (!done.insert(uri).second) return;
             try {
                 stores.push_back(openStore(uri));
             } catch (Error & e) {
diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index 5733bd9de..a9b073be4 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -629,6 +629,9 @@ public:
         return storePath;
     }
 
+    virtual void createUser(const std::string & userName, uid_t userId)
+    { }
+
 protected:
 
     Stats stats;
diff --git a/src/libutil/json.cc b/src/libutil/json.cc
index 0a6fb65f0..74e37b4c4 100644
--- a/src/libutil/json.cc
+++ b/src/libutil/json.cc
@@ -171,4 +171,9 @@ JSONObject JSONPlaceholder::object()
     return JSONObject(state);
 }
 
+JSONPlaceholder::~JSONPlaceholder()
+{
+    assert(!first || std::uncaught_exception());
+}
+
 }
diff --git a/src/libutil/json.hh b/src/libutil/json.hh
index 02a39917f..83213ca66 100644
--- a/src/libutil/json.hh
+++ b/src/libutil/json.hh
@@ -168,10 +168,7 @@ public:
     {
     }
 
-    ~JSONPlaceholder()
-    {
-        assert(!first || std::uncaught_exception());
-    }
+    ~JSONPlaceholder();
 
     template<typename T>
     void write(const T & v)
diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 98a7ea397..9d6bec034 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -486,6 +486,16 @@ std::pair<AutoCloseFD, Path> createTempFile(const Path & prefix)
 }
 
 
+std::string getUserName()
+{
+    auto pw = getpwuid(geteuid());
+    std::string name = pw ? pw->pw_name : getEnv("USER", "");
+    if (name.empty())
+        throw Error("cannot figure out user name");
+    return name;
+}
+
+
 static Lazy<Path> getHome2([]() {
     Path homeDir = getEnv("HOME");
     if (homeDir.empty()) {
diff --git a/src/libutil/util.hh b/src/libutil/util.hh
index 2bf9725af..9f8c7092d 100644
--- a/src/libutil/util.hh
+++ b/src/libutil/util.hh
@@ -122,6 +122,12 @@ void deletePath(const Path & path);
 
 void deletePath(const Path & path, unsigned long long & bytesFreed);
 
+/* Create a temporary directory. */
+Path createTempDir(const Path & tmpRoot = "", const Path & prefix = "nix",
+    bool includePid = true, bool useGlobalCounter = true, mode_t mode = 0755);
+
+std::string getUserName();
+
 /* Return $HOME or the user's home directory from /etc/passwd. */
 Path getHome();
 
diff --git a/src/nix-build/nix-build.cc b/src/nix-build/nix-build.cc
index 53a564676..50909608a 100755
--- a/src/nix-build/nix-build.cc
+++ b/src/nix-build/nix-build.cc
@@ -412,7 +412,7 @@ static void _main(int argc, char * * argv)
         auto rcfile = (Path) tmpDir + "/rc";
         writeFile(rcfile, fmt(
                 (keepTmp ? "" : "rm -rf '%1%'; "s) +
-                "[ -n \"$PS1\" ] && [ -e ~/.bashrc ] && source ~/.bashrc; "
+                (pure ? "" : "[ -n \"$PS1\" ] && [ -e ~/.bashrc ] && source ~/.bashrc;") +
                 "%2%"
                 "dontAddDisableDepTrack=1; "
                 "[ -e $stdenv/setup ] && source $stdenv/setup; "
diff --git a/src/nix-channel/nix-channel.cc b/src/nix-channel/nix-channel.cc
index 06eb3d23b..70aa5c966 100755
--- a/src/nix-channel/nix-channel.cc
+++ b/src/nix-channel/nix-channel.cc
@@ -159,13 +159,7 @@ static int _main(int argc, char ** argv)
         nixDefExpr = home + "/.nix-defexpr";
 
         // Figure out the name of the channels profile.
-        ;
-        auto pw = getpwuid(geteuid());
-        std::string name = pw ? pw->pw_name : getEnv("USER", "");
-        if (name.empty())
-            throw Error("cannot figure out user name");
-        profile = settings.nixStateDir + "/profiles/per-user/" + name + "/channels";
-        createDirs(dirOf(profile));
+        profile = fmt("%s/profiles/per-user/%s/channels", settings.nixStateDir, getUserName());
 
         enum {
             cNone,
diff --git a/src/nix-daemon/nix-daemon.cc b/src/nix-daemon/nix-daemon.cc
index e88aaf636..cd18489b0 100644
--- a/src/nix-daemon/nix-daemon.cc
+++ b/src/nix-daemon/nix-daemon.cc
@@ -742,7 +742,8 @@ static void performOp(TunnelLogger * logger, ref<Store> store,
 }
 
 
-static void processConnection(bool trusted)
+static void processConnection(bool trusted,
+    const std::string & userName, uid_t userId)
 {
     MonitorFdHup monitor(from.fd);
 
@@ -793,6 +794,8 @@ static void processConnection(bool trusted)
         params["path-info-cache-size"] = "0";
         auto store = openStore(settings.storeUri, params);
 
+        store->createUser(userName, userId);
+
         tunnelLogger->stopWork();
         to.flush();
 
@@ -1053,7 +1056,7 @@ static void daemonLoop(char * * argv)
                 /* Handle the connection. */
                 from.fd = remote.get();
                 to.fd = remote.get();
-                processConnection(trusted);
+                processConnection(trusted, user, peer.uid);
 
                 exit(0);
             }, options);
@@ -1133,7 +1136,7 @@ static int _main(int argc, char * * argv)
                     }
                 }
             } else {
-                processConnection(true);
+                processConnection(true, "root", 0);
             }
         } else {
             daemonLoop(argv);
diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc
index 87b2e43f0..199dc92aa 100644
--- a/src/nix-env/nix-env.cc
+++ b/src/nix-env/nix-env.cc
@@ -124,11 +124,10 @@ static void getAllExprs(EvalState & state,
             string attrName = i;
             if (hasSuffix(attrName, ".nix"))
                 attrName = string(attrName, 0, attrName.size() - 4);
-            if (attrs.find(attrName) != attrs.end()) {
+            if (!attrs.insert(attrName).second) {
                 printError(format("warning: name collision in input Nix expressions, skipping '%1%'") % path2);
                 continue;
             }
-            attrs.insert(attrName);
             /* Load the expression on demand. */
             Value & vFun = state.getBuiltin("import");
             Value & vArg(*state.allocValue());
@@ -193,12 +192,6 @@ static void loadDerivations(EvalState & state, Path nixExprPath,
 }
 
 
-static Path getDefNixExprPath()
-{
-    return getHome() + "/.nix-defexpr";
-}
-
-
 static long getPriority(EvalState & state, DrvInfo & drv)
 {
     return drv.queryMetaInt("priority", 0);
@@ -307,10 +300,8 @@ static DrvInfos filterBySelector(EvalState & state, const DrvInfos & allElems,
         /* Insert only those elements in the final list that we
            haven't inserted before. */
         for (auto & j : matches)
-            if (done.find(j.second) == done.end()) {
-                done.insert(j.second);
+            if (done.insert(j.second).second)
                 elems.push_back(j.first);
-            }
     }
 
     checkSelectorUse(selectors);
@@ -1330,9 +1321,22 @@ static int _main(int argc, char * * argv)
         Globals globals;
 
         globals.instSource.type = srcUnknown;
-        globals.instSource.nixExprPath = getDefNixExprPath();
+        globals.instSource.nixExprPath = getHome() + "/.nix-defexpr";
         globals.instSource.systemFilter = "*";
 
+        if (!pathExists(globals.instSource.nixExprPath)) {
+            try {
+                createDirs(globals.instSource.nixExprPath);
+                replaceSymlink(
+                    fmt("%s/profiles/per-user/%s/channels", settings.nixStateDir, getUserName()),
+                    globals.instSource.nixExprPath + "/channels");
+                if (getuid() != 0)
+                    replaceSymlink(
+                        fmt("%s/profiles/per-user/root/channels", settings.nixStateDir),
+                        globals.instSource.nixExprPath + "/channels_root");
+            } catch (Error &) { }
+        }
+
         globals.dryRun = false;
         globals.preserveInstalled = false;
         globals.removeAll = false;
@@ -1425,9 +1429,18 @@ static int _main(int argc, char * * argv)
 
         if (globals.profile == "") {
             Path profileLink = getHome() + "/.nix-profile";
-            globals.profile = pathExists(profileLink)
-                ? absPath(readLink(profileLink), dirOf(profileLink))
-                : canonPath(settings.nixStateDir + "/profiles/default");
+            try {
+                if (!pathExists(profileLink)) {
+                    replaceSymlink(
+                        getuid() == 0
+                        ? settings.nixStateDir + "/profiles/default"
+                        : fmt("%s/profiles/per-user/%s/profile", settings.nixStateDir, getUserName()),
+                        profileLink);
+                }
+                globals.profile = absPath(readLink(profileLink), dirOf(profileLink));
+            } catch (Error &) {
+                globals.profile = profileLink;
+            }
         }
 
         op(globals, opFlags, opArgs);
diff --git a/src/nix-store/dotgraph.cc b/src/nix-store/dotgraph.cc
index abdfa5e58..d448654fe 100644
--- a/src/nix-store/dotgraph.cc
+++ b/src/nix-store/dotgraph.cc
@@ -71,9 +71,7 @@ void printClosure(const Path & nePath, const StoreExpr & fs)
         Path path = *(workList.begin());
         workList.erase(path);
 
-        if (doneSet.find(path) == doneSet.end()) {
-            doneSet.insert(path);
-
+        if (doneSet.insert(path).second) {
             ClosureElems::const_iterator elem = fs.closure.elems.find(path);
             if (elem == fs.closure.elems.end())
                 throw Error(format("bad closure, missing path '%1%'") % path);
@@ -104,8 +102,7 @@ void printDotGraph(ref<Store> store, const PathSet & roots)
         Path path = *(workList.begin());
         workList.erase(path);
 
-        if (doneSet.find(path) != doneSet.end()) continue;
-        doneSet.insert(path);
+        if (!doneSet.insert(path).second) continue;
 
         cout << makeNode(path, symbolicName(path), "#ff0000");
 
diff --git a/src/nix-store/nix-store.cc b/src/nix-store/nix-store.cc
index 0cbceb02f..19384499d 100644
--- a/src/nix-store/nix-store.cc
+++ b/src/nix-store/nix-store.cc
@@ -242,11 +242,10 @@ const string treeNull = "    ";
 static void printTree(const Path & path,
     const string & firstPad, const string & tailPad, PathSet & done)
 {
-    if (done.find(path) != done.end()) {
+    if (!done.insert(path).second) {
         cout << format("%1%%2% [...]\n") % firstPad % path;
         return;
     }
-    done.insert(path);
 
     cout << format("%1%%2%\n") % firstPad % path;
 
diff --git a/src/nix/progress-bar.cc b/src/nix/progress-bar.cc
index c0bcfb0c9..5c05d6b22 100644
--- a/src/nix/progress-bar.cc
+++ b/src/nix/progress-bar.cc
@@ -120,7 +120,7 @@ public:
     void log(State & state, Verbosity lvl, const std::string & s)
     {
         if (state.active) {
-            writeToStderr("\r\e[K" + s + ANSI_NORMAL "\n");
+            writeToStderr("\r\e[K" + filterANSIEscapes(s, !isTTY) + ANSI_NORMAL "\n");
             draw(state);
         } else {
             auto s2 = s + ANSI_NORMAL "\n";
diff --git a/src/nix/search.cc b/src/nix/search.cc
index 70de717d1..caea25cdc 100644
--- a/src/nix/search.cc
+++ b/src/nix/search.cc
@@ -75,10 +75,6 @@ struct CmdSearch : SourceExprCommand, MixJSON
             Example{
                 "To search for git and frontend or gui:",
                 "nix search git 'frontend|gui'"
-            },
-            Example{
-                "To display the description of the found packages:",
-                "nix search git --verbose"
             }
         };
     }
@@ -262,6 +258,7 @@ struct CmdSearch : SourceExprCommand, MixJSON
                    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66145 */
                 if (!jsonCacheFile)
                     throw Error("error writing to %s", tmpFile);
+                throw;
             }
 
             if (writeCache && rename(tmpFile.c_str(), jsonCacheFileName.c_str()) == -1)
diff --git a/src/nix/verify.cc b/src/nix/verify.cc
index f55766eda..81abf434f 100644
--- a/src/nix/verify.cc
+++ b/src/nix/verify.cc
@@ -113,8 +113,7 @@ struct CmdVerify : StorePathsCommand
 
                         auto doSigs = [&](StringSet sigs) {
                             for (auto sig : sigs) {
-                                if (sigsSeen.count(sig)) continue;
-                                sigsSeen.insert(sig);
+                                if (!sigsSeen.insert(sig).second) continue;
                                 if (validSigs < ValidPathInfo::maxSigs && info->checkSignature(publicKeys, sig))
                                     validSigs++;
                             }
diff --git a/src/resolve-system-dependencies/resolve-system-dependencies.cc b/src/resolve-system-dependencies/resolve-system-dependencies.cc
index e02cfc03e..45e8b6796 100644
--- a/src/resolve-system-dependencies/resolve-system-dependencies.cc
+++ b/src/resolve-system-dependencies/resolve-system-dependencies.cc
@@ -117,9 +117,7 @@ Path resolveSymlink(const Path & path)
 std::set<string> resolveTree(const Path & path, PathSet & deps)
 {
     std::set<string> results;
-    if (deps.count(path))
-        return {};
-    deps.insert(path);
+    if (!deps.insert(path).second) return {};
     for (auto & lib : runResolver(path)) {
         results.insert(lib);
         for (auto & p : resolveTree(lib, deps)) {