Add proper support for option files option to load_default_options()

4 files changed, 88 insertions, 38 deletions

diff --git a/libbutl/default-options.mxx b/libbutl/default-options.mxx
index aeb246d..11f7bb2 100644
--- a/libbutl/default-options.mxx
+++ b/libbutl/default-options.mxx
@@ -61,10 +61,12 @@ LIBBUTL_MODEXPORT namespace butl
   using default_options = small_vector<default_options_entry<O>, 4>;
 
   // Search for and load the specified list of options files in the specified
-  // directories returning a vector of option class instances (O). If args is
-  // false, only options are allowed and are parsed using scanner S in the
-  // U::fail mode. If args is true, then both options and arguments are
-  // allowed in any order with options parsed in the U::stop mode.
+  // directories returning a vector of option class instances (O). Read
+  // additional options from files referenced by the specified option
+  // (normally --options-file). If args is false, only options are allowed and
+  // are parsed using scanner S in the U::fail mode. If args is true, then
+  // both options and arguments are allowed in any order with options parsed
+  // in the U::stop mode.
   //
   // Pass each default options file path to the specified function prior to
   // load (can be used for tracing, etc). The function signature is:
@@ -112,6 +114,7 @@ LIBBUTL_MODEXPORT namespace butl
                         const optional<dir_path>& extra_dir,
                         const default_options_files&,
                         F&&,
+                        const std::string& option,
                         bool args = false);
 
   // Merge the default options/arguments and the command line
diff --git a/libbutl/default-options.txx b/libbutl/default-options.txx
index 5245bd6..eaf4235 100644
--- a/libbutl/default-options.txx
+++ b/libbutl/default-options.txx
@@ -31,6 +31,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
   template <typename O, typename S, typename U, typename F>
   bool
   load_default_options_files (const dir_path& d,
+                              const std::string& opt,
                               bool args,
                               bool remote,
                               const small_vector<path, 2>& fs,
@@ -43,7 +44,8 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
 
     bool r (true);
 
-    auto load = [args, &fs, &fn, &def_ops, &r] (const dir_path& d, bool rem)
+    auto load = [&opt, args, &fs, &fn, &def_ops, &r]
+                (const dir_path& d, bool rem)
     {
       using namespace std;
 
@@ -57,7 +59,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
           {
             fn (p, rem, false /* overwrite */);
 
-            S s (p.string ());
+            S s (p.string (), opt);
 
             // @@ Note that the potentially thrown exceptions (unknown option,
             //    unexpected argument, etc) will not contain any location
@@ -66,7 +68,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
             //    this in CLI.
             //
             O o;
-            small_vector<std::string, 1> as;
+            small_vector<string, 1> as;
 
             if (args)
             {
@@ -88,9 +90,9 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
                                                          rem});
           }
         }
-        catch (std::system_error& e)
+        catch (system_error& e)
         {
-          throw std::make_pair (move (p), std::move (e));
+          throw make_pair (move (p), move (e));
         }
       }
     };
@@ -116,6 +118,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
                         const optional<dir_path>& extra_dir,
                         const default_options_files& ofs,
                         F&& fn,
+                        const std::string& opt,
                         bool args)
   {
     if (sys_dir)
@@ -206,6 +209,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
           if (load_extra && extra_dir->sub (d))
           {
             load = load_default_options_files<O, S, U> (*extra_dir,
+                                                        opt,
                                                         args,
                                                         false /* remote */,
                                                         ofs.files,
@@ -219,6 +223,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
 
           if (load && options_dir_exists (od))
             load = load_default_options_files<O, S, U> (od,
+                                                        opt,
                                                         args,
                                                         remote,
                                                         ofs.files,
@@ -235,6 +240,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
 
     if (load && load_extra)
       load = load_default_options_files<O, S, U> (*extra_dir,
+                                                  opt,
                                                   args,
                                                   false /* remote */,
                                                   ofs.files,
@@ -247,6 +253,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
 
       if (options_dir_exists (d))
         load = load_default_options_files<O, S, U> (d,
+                                                    opt,
                                                     args,
                                                     false /* remote */,
                                                     ofs.files,
@@ -256,6 +263,7 @@ LIBBUTL_MODEXPORT namespace butl //@@ MOD Clang needs this for some reason.
 
     if (load && sys_dir && options_dir_exists (*sys_dir))
       load_default_options_files<O, S, U> (*sys_dir,
+                                           opt,
                                            args,
                                            false /* remote */,
                                            ofs.files,
diff --git a/tests/default-options/driver.cxx b/tests/default-options/driver.cxx
index 574e002..b3f66bf 100644
--- a/tests/default-options/driver.cxx
+++ b/tests/default-options/driver.cxx
@@ -35,7 +35,7 @@ using namespace std;
 using namespace butl;
 
 // Usage: argv[0] [-f <file>] [-d <start-dir>] [-s <sys-dir>] [-h <home-dir>]
-//                [-x <extra-dir>] [-e] [-t] <cmd-options>
+//                [-x <extra-dir>] [-a] [-e] [-t] <cmd-options>
 //
 // Parse default options files, merge them with the command line options, and
 // print the resulting options to STDOUT one per line. Note that the options
@@ -78,56 +78,61 @@ main (int argc, const char* argv[])
   class scanner
   {
   public:
-    scanner (const string& f): ifs_ (f, fdopen_mode::in, ifdstream::badbit) {}
+    scanner (const string& f, const string& option)
+        : option_ (option) {load (path (f));}
 
     bool
     more ()
     {
-      if (peeked_)
-        return true;
-
-      if (!eof_)
-        eof_ = ifs_.peek () == ifdstream::traits_type::eof ();
-
-      return !eof_;
+      return i_ < args_.size ();
     }
 
     string
     peek ()
     {
       assert (more ());
-
-      if (peeked_)
-        return *peeked_;
-
-      string s;
-      getline (ifs_, s);
-
-      peeked_ = move (s);
-      return *peeked_;
+      return args_[i_];
     }
 
     string
     next ()
     {
       assert (more ());
+      return args_[i_++];
+    }
+
+  private:
+    void
+    load (const path& f)
+    {
+      ifdstream is (f, fdopen_mode::in, ifdstream::badbit);
 
-      string s;
-      if (peeked_)
+      for (string l; !eof (getline (is, l)); )
       {
-        s = move (*peeked_);
-        peeked_ = nullopt;
-      }
-      else
-        getline (ifs_, s);
+        if (option_ && *option_ == l)
+        {
+          assert (!eof (getline (is, l)));
 
-      return s;
+          // If the path of the file being parsed is not simple and the path
+          // of the file that needs to be loaded is relative, then complete
+          // the latter using the former as a base.
+          //
+          path p (l);
+
+          if (!f.simple () && p.relative ())
+            p = f.directory () / p;
+
+          load (p);
+        }
+        else
+          args_.push_back (move (l));
+      }
     }
 
   private:
-    ifdstream ifs_;
-    bool eof_ = false;
-    optional<string> peeked_;
+    optional<string> option_;
+    vector<string> args_;
+    size_t i_ = 0;
   };
 
   enum class unknow_mode
@@ -264,6 +269,7 @@ main (int argc, const char* argv[])
           cerr << (overwrite ? "overwriting " : "loading ")
                << (remote ? "remote " : "local ") << f << endl;
       },
+      "--options-file",
       args);
   }
   catch (const invalid_argument& e)
diff --git a/tests/default-options/testscript b/tests/default-options/testscript
index b168ca9..09bb2ec 100644
--- a/tests/default-options/testscript
+++ b/tests/default-options/testscript
@@ -345,3 +345,36 @@
       EOO
   }
 }
+
+: options-file
+:
+{
+  d = work/.build2;
+  mkdir -p work/.build2;
+
+  cat <<EOI >=$d/foo;
+    --foo
+    --options-file
+    bar
+    --fox
+    EOI
+
+  cat <<EOI >=$d/bar;
+    --bar
+    --options-file
+    baz
+    --box
+    EOI
+
+  cat <<EOI >=$d/baz;
+    --baz
+    EOI
+
+  $* -d $~/work -f foo >>EOO
+    --foo
+    --bar
+    --baz
+    --box
+    --fox
+    EOO
+}