Shell completion improvements

misc/bash/completion.sh

@@ -15,7 +15,7 @@ function _complete_nix {
         else
             COMPREPLY+=("$completion")
         fi
-    done < <(NIX_GET_COMPLETIONS=$cword "${words[@]/#\~/$HOME}" 2>/dev/null)
+    done < <(NIX_GET_COMPLETIONS=$cword "${words[@]}" 2>/dev/null)
     __ltrim_colon_completions "$cur"
 }
 

src/libcmd/command.hh

@@ -134,7 +134,7 @@ struct InstallableCommand : virtual Args, SourceExprCommand
 
     std::optional<FlakeRef> getFlakeRefForCompletion() override
     {
-        return parseFlakeRef(_installable, absPath("."));
+        return parseFlakeRefWithFragment(_installable, absPath(".")).first;
     }
 
 private:

src/libexpr/common-eval-args.cc → src/libcmd/common-eval-args.cc

@@ -7,6 +7,7 @@
 #include "registry.hh"
 #include "flake/flakeref.hh"
 #include "store-api.hh"
+#include "command.hh"
 
 namespace nix {
 
@@ -59,6 +60,9 @@ MixEvalArgs::MixEvalArgs()
             fetchers::Attrs extraAttrs;
             if (to.subdir != "") extraAttrs["dir"] = to.subdir;
             fetchers::overrideRegistry(from.input, to.input, extraAttrs);
+        }},
+        .completer = {[&](size_t, std::string_view prefix) {
+            completeFlakeRef(openStore(), prefix);
         }}
     });
 

src/libcmd/installables.cc

@@ -1,4 +1,5 @@
 #include "installables.hh"
+#include "util.hh"
 #include "command.hh"
 #include "attr-path.hh"
 #include "common-eval-args.hh"
@@ -98,6 +99,14 @@ MixFlakeOptions::MixFlakeOptions()
             lockFlags.inputOverrides.insert_or_assign(
                 flake::parseInputPath(inputPath),
                 parseFlakeRef(flakeRef, absPath("."), true));
+        }},
+        .completer = {[&](size_t n, std::string_view prefix) {
+            if (n == 0) {
+                if (auto flakeRef = getFlakeRefForCompletion())
+                    completeFlakeInputPath(getEvalState(), *flakeRef, prefix);
+            } else if (n == 1) {
+                completeFlakeRef(getEvalState()->store, prefix);
+            }
         }}
     });
 
@@ -179,6 +188,8 @@ Strings SourceExprCommand::getDefaultFlakeAttrPathPrefixes()
 void SourceExprCommand::completeInstallable(std::string_view prefix)
 {
     if (file) {
+        completionType = ctAttrs;
+
         evalSettings.pureEval = false;
         auto state = getEvalState();
         Expr *e = state->parseExprFromFile(
@@ -207,13 +218,14 @@ void SourceExprCommand::completeInstallable(std::string_view prefix)
         Value v2;
         state->autoCallFunction(*autoArgs, v1, v2);
 
-        completionType = ctAttrs;
-
         if (v2.type() == nAttrs) {
             for (auto & i : *v2.attrs) {
                 std::string name = i.name;
                 if (name.find(searchWord) == 0) {
-                    completions->add(i.name);
+                    if (prefix_ == "")
+                        completions->add(name);
+                    else
+                        completions->add(prefix_ + "." + name);
                 }
             }
         }
@@ -241,10 +253,11 @@ void completeFlakeRefWithFragment(
         if (hash == std::string::npos) {
             completeFlakeRef(evalState->store, prefix);
         } else {
+            completionType = ctAttrs;
+
             auto fragment = prefix.substr(hash + 1);
             auto flakeRefS = std::string(prefix.substr(0, hash));
-            // FIXME: do tilde expansion.
-            auto flakeRef = parseFlakeRef(flakeRefS, absPath("."));
+            auto flakeRef = parseFlakeRef(expandTilde(flakeRefS), absPath("."));
 
             auto evalCache = openEvalCache(*evalState,
                 std::make_shared<flake::LockedFlake>(lockFlake(*evalState, flakeRef, lockFlags)));
@@ -256,8 +269,6 @@ void completeFlakeRefWithFragment(
                flake. */
             attrPathPrefixes.push_back("");
 
-            completionType = ctAttrs;
-
             for (auto & attrPathPrefixS : attrPathPrefixes) {
                 auto attrPathPrefix = parseAttrPath(*evalState, attrPathPrefixS);
                 auto attrPathS = attrPathPrefixS + std::string(fragment);
@@ -905,10 +916,10 @@ std::optional<FlakeRef> InstallablesCommand::getFlakeRefForCompletion()
 {
     if (_installables.empty()) {
         if (useDefaultInstallables())
-            return parseFlakeRef(".", absPath("."));
+            return parseFlakeRefWithFragment(".", absPath(".")).first;
         return {};
     }
-    return parseFlakeRef(_installables.front(), absPath("."));
+    return parseFlakeRefWithFragment(_installables.front(), absPath(".")).first;
 }
 
 InstallableCommand::InstallableCommand()

src/libutil/args.cc

@@ -127,11 +127,11 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end)
                 if (flag.handler.arity == ArityAny) break;
                 throw UsageError("flag '%s' requires %d argument(s)", name, flag.handler.arity);
             }
-            if (flag.completer)
-                if (auto prefix = needsCompletion(*pos)) {
-                    anyCompleted = true;
+            if (auto prefix = needsCompletion(*pos)) {
+                anyCompleted = true;
+                if (flag.completer)
                     flag.completer(n, *prefix);
-                }
+            }
             args.push_back(*pos++);
         }
         if (!anyCompleted)
@@ -146,6 +146,7 @@ bool Args::processFlag(Strings::iterator & pos, Strings::iterator end)
                     && hasPrefix(name, std::string(*prefix, 2)))
                     completions->add("--" + name, flag->description);
             }
+            return false;
         }
         auto i = longFlags.find(std::string(*pos, 2));
         if (i == longFlags.end()) return false;
@@ -187,10 +188,12 @@ bool Args::processArgs(const Strings & args, bool finish)
     {
         std::vector<std::string> ss;
         for (const auto &[n, s] : enumerate(args)) {
-            ss.push_back(s);
-            if (exp.completer)
-                if (auto prefix = needsCompletion(s))
+            if (auto prefix = needsCompletion(s)) {
+                ss.push_back(*prefix);
+                if (exp.completer)
                     exp.completer(n, *prefix);
+            } else
+                ss.push_back(s);
         }
         exp.handler.fun(ss);
         expectedArgs.pop_front();
@@ -279,21 +282,22 @@ static void _completePath(std::string_view prefix, bool onlyDirs)
 {
     completionType = ctFilenames;
     glob_t globbuf;
-    int flags = GLOB_NOESCAPE | GLOB_TILDE;
+    int flags = GLOB_NOESCAPE;
     #ifdef GLOB_ONLYDIR
     if (onlyDirs)
         flags |= GLOB_ONLYDIR;
     #endif
-    if (glob((std::string(prefix) + "*").c_str(), flags, nullptr, &globbuf) == 0) {
+    // using expandTilde here instead of GLOB_TILDE(_CHECK) so that ~<Tab> expands to /home/user/
+    if (glob((expandTilde(prefix) + "*").c_str(), flags, nullptr, &globbuf) == 0) {
         for (size_t i = 0; i < globbuf.gl_pathc; ++i) {
             if (onlyDirs) {
-                auto st = lstat(globbuf.gl_pathv[i]);
+                auto st = stat(globbuf.gl_pathv[i]);
                 if (!S_ISDIR(st.st_mode)) continue;
             }
             completions->add(globbuf.gl_pathv[i]);
         }
-        globfree(&globbuf);
     }
+    globfree(&globbuf);
 }
 
 void completePath(size_t, std::string_view prefix)
@@ -322,16 +326,16 @@ MultiCommand::MultiCommand(const Commands & commands_)
         .optional = true,
         .handler = {[=](std::string s) {
             assert(!command);
-            if (auto prefix = needsCompletion(s)) {
-                for (auto & [name, command] : commands)
-                    if (hasPrefix(name, *prefix))
-                        completions->add(name);
-            }
             auto i = commands.find(s);
             if (i == commands.end())
                 throw UsageError("'%s' is not a recognised command", s);
             command = {s, i->second()};
             command->second->parent = this;
+        }},
+        .completer = {[&](size_t, std::string_view prefix) {
+            for (auto & [name, command] : commands)
+                if (hasPrefix(name, prefix))
+                    completions->add(name);
         }}
     });
 

src/libutil/util.cc

@@ -200,6 +200,17 @@ std::string_view baseNameOf(std::string_view path)
 }
 
 
+std::string expandTilde(std::string_view path)
+{
+    // TODO: expand ~user ?
+    auto tilde = path.substr(0, 2);
+    if (tilde == "~/" || tilde == "~")
+        return getHome() + std::string(path.substr(1));
+    else
+        return std::string(path);
+}
+
+
 bool isInDir(std::string_view path, std::string_view dir)
 {
     return path.substr(0, 1) == "/"
@@ -215,6 +226,15 @@ bool isDirOrInDir(std::string_view path, std::string_view dir)
 }
 
 
+struct stat stat(const Path & path)
+{
+    struct stat st;
+    if (stat(path.c_str(), &st))
+        throw SysError("getting status of '%1%'", path);
+    return st;
+}
+
+
 struct stat lstat(const Path & path)
 {
     struct stat st;

src/libutil/util.hh

@@ -68,6 +68,9 @@ Path dirOf(const PathView path);
    following the final `/' (trailing slashes are removed). */
 std::string_view baseNameOf(std::string_view path);
 
+/* Perform tilde expansion on a path. */
+std::string expandTilde(std::string_view path);
+
 /* Check whether 'path' is a descendant of 'dir'. Both paths must be
    canonicalized. */
 bool isInDir(std::string_view path, std::string_view dir);
@@ -77,6 +80,7 @@ bool isInDir(std::string_view path, std::string_view dir);
 bool isDirOrInDir(std::string_view path, std::string_view dir);
 
 /* Get status of `path'. */
+struct stat stat(const Path & path);
 struct stat lstat(const Path & path);
 
 /* Return true iff the given path exists. */