Implement dependents check in drop command

Also, add support for commands to return program status.

36 files changed, 192 insertions, 47 deletions

diff --git a/bpkg/bpkg.cxx b/bpkg/bpkg.cxx
index 61f7425..6246d6f 100644
--- a/bpkg/bpkg.cxx
+++ b/bpkg/bpkg.cxx
@@ -145,6 +145,7 @@ try
 
   // Handle commands.
   //
+  int r (1);
   for (;;)
   {
     // help
@@ -152,7 +153,7 @@ try
     if (cmd.help ())
     {
       assert (h);
-      help (ho, "help", help_options::print_usage);
+      r = help (ho, "help", help_options::print_usage);
       break;
     }
 
@@ -163,7 +164,7 @@ try
     //  if (h)
     //    help (ho, "pkg-verify", pkg_verify_options::print_usage);
     //  else
-    //    pkg_verify (parse<pkg_verify_options> (co, args), args);
+    //    r = pkg_verify (parse<pkg_verify_options> (co, args), args);
     //
     //  return 0;
     // }
@@ -174,7 +175,7 @@ try
       if (h)                                                            \
         help (ho, SP#CMD, NP##CMD##_options::print_usage);              \
       else                                                              \
-        NP##CMD (parse<NP##CMD##_options> (co, args), args);            \
+        r = NP##CMD (parse<NP##CMD##_options> (co, args), args);        \
                                                                         \
       break;                                                            \
     }
@@ -219,6 +220,9 @@ try
     fail << "unhandled command";
   }
 
+  if (r != 0)
+    return r;
+
   // Warn if args contain some leftover junk. We already successfully
   // performed the command so failing would probably be misleading.
   //
diff --git a/bpkg/build b/bpkg/build
index cc89599..a5c047d 100644
--- a/bpkg/build
+++ b/bpkg/build
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   build (const build_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/build.cxx b/bpkg/build.cxx
index ec9de3b..1aeb35d 100644
--- a/bpkg/build.cxx
+++ b/bpkg/build.cxx
@@ -731,7 +731,7 @@ namespace bpkg
     map_type map_;
   };
 
-  void
+  int
   build (const build_options& o, cli::scanner& args)
   {
     tracer trace ("build");
@@ -1029,12 +1029,12 @@ namespace bpkg
     }
 
     if (o.print_only ())
-      return;
+      return 0;
 
     // Ask the user if we should continue.
     //
     if (!(o.yes () || yn_prompt ("continue? [Y/n]", 'y')))
-      return;
+      return 1;
 
     // Ok, we have the green light. The overall action plan is as follows.
     //
@@ -1230,5 +1230,7 @@ namespace bpkg
           text << "updated " << sp->name << " " << sp->version;
       }
     }
+
+    return 0;
   }
 }
diff --git a/bpkg/cfg-create b/bpkg/cfg-create
index ffd3ba5..b6dcc21 100644
--- a/bpkg/cfg-create
+++ b/bpkg/cfg-create
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   cfg_create (const cfg_create_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/cfg-create.cxx b/bpkg/cfg-create.cxx
index bbb624c..c98dd28 100644
--- a/bpkg/cfg-create.cxx
+++ b/bpkg/cfg-create.cxx
@@ -18,7 +18,7 @@ using namespace butl;
 
 namespace bpkg
 {
-  void
+  int
   cfg_create (const cfg_create_options& o, cli::scanner& args)
   {
     tracer trace ("cfg_create");
@@ -130,5 +130,7 @@ namespace bpkg
       c.complete ().normalize ();
       text << "created new configuration in " << c;
     }
+
+    return 0;
   }
 }
diff --git a/bpkg/drop b/bpkg/drop
index 1687c82..0054045 100644
--- a/bpkg/drop
+++ b/bpkg/drop
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   drop (const drop_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/drop-options.cli b/bpkg/drop-options.cli
index 301bc9a..d1a3769 100644
--- a/bpkg/drop-options.cli
+++ b/bpkg/drop-options.cli
@@ -31,10 +31,17 @@ namespace bpkg
     bool --yes|-y
     {
       "Assume the answer to all prompts is \cb{yes}. Note that this option
-       does not apply to the dropping of dependents confirmation."
+       does not apply to the dropping of dependents; use \cb{--drop-dependent}
+       for that."
     };
 
-    bool --disfigure-only|-d
+    bool --drop-dependent
+    {
+      "Don't warn about or ask for confirmation of dropping dependent
+       packages."
+    };
+
+    bool --disfigure-only
     {
       "Disfigure all the packages but don't purge."
     };
diff --git a/bpkg/drop.cxx b/bpkg/drop.cxx
index ac3919e..e2fd455 100644
--- a/bpkg/drop.cxx
+++ b/bpkg/drop.cxx
@@ -4,6 +4,7 @@
 
 #include <bpkg/drop>
 
+#include <map>
 #include <iostream>   // cout
 
 #include <butl/utility> // reverse_iterate()
@@ -27,7 +28,41 @@ using namespace butl;
 
 namespace bpkg
 {
-  void
+  using package_map = map<string, shared_ptr<selected_package>>;
+
+  static void
+  collect_dependent (database& db,
+                     package_map& m,
+                     const shared_ptr<selected_package>& p,
+                     bool w)
+  {
+    using query = query<package_dependent>;
+
+    bool found (false);
+
+    for (auto& pd: db.query<package_dependent> (query::name == p->name))
+    {
+      string& dn (pd.name);
+
+      if (m.find (dn) == m.end ())
+      {
+        shared_ptr<selected_package> dp (db.load<selected_package> (dn));
+        m.emplace (move (dn), dp);
+
+        collect_dependent (db, m, dp, w);
+
+        if (w)
+          warn << "dependent package " << dp->name << " to be dropped as well";
+
+        found = true;
+      }
+    }
+
+    if (w && found)
+      info << "because dropping " << p->name;
+  }
+
+  int
   drop (const drop_options& o, cli::scanner& args)
   {
     tracer trace ("drop");
@@ -47,6 +82,68 @@ namespace bpkg
     // any of these objects, they will modify the cached instance, which
     // means our list will always "see" their updated state.
     //
+    // @@ Revise.
+    //
     session s;
+
+    // Assemble the list of packages we will need to drop. Comparing pointers
+    // is valid because of the session above.
+    //
+    package_map pkgs;
+    vector<string> names;
+    {
+      transaction t (db.begin ());
+
+      // The first step is to load all the packages specified by the user.
+      //
+      while (args.more ())
+      {
+        string n (args.next ());
+        level4 ([&]{trace << "package " << n;});
+
+        shared_ptr<selected_package> p (db.find<selected_package> (n));
+
+        if (p == nullptr)
+          fail << "package " << n << " does not exist in configuration " << c;
+
+        if (p->state == package_state::broken)
+          fail << "unable to drop broken package " << n <<
+            info << "use 'pkg-purge --force' to remove";
+
+        if (pkgs.emplace (n, move (p)).second)
+          names.push_back (move (n));
+      }
+
+      // The next step is to see if there are any dependents that are not
+      // already on the list. We will have to drop those as well.
+      //
+      for (const string& n: names)
+      {
+        const shared_ptr<selected_package>& p (pkgs[n]);
+
+        // Unconfigured package cannot have any dependents.
+        //
+        if (p->state != package_state::configured)
+          continue;
+
+        collect_dependent (db, pkgs, p, !o.drop_dependent ());
+      }
+
+      // If we've found dependents, ask the user to confirm.
+      //
+      if (!o.drop_dependent () && names.size () != pkgs.size ())
+      {
+        if (o.yes ())
+          fail << "refusing to drop dependent packages with just --yes" <<
+            info << "specify --drop-dependent to confirm";
+
+        if (!yn_prompt ("drop dependent packages? [y/N]", 'n'))
+          return 1;
+      }
+
+      t.commit ();
+    }
+
+    return 0;
   }
 }
diff --git a/bpkg/help b/bpkg/help
index 9c81e7e..8bd5596 100644
--- a/bpkg/help
+++ b/bpkg/help
@@ -12,7 +12,7 @@
 
 namespace bpkg
 {
-  void
+  int
   help (const help_options&,
         const string& topic,
         void (*usage) (std::ostream&));
diff --git a/bpkg/help.cxx b/bpkg/help.cxx
index 66b68aa..f03ad21 100644
--- a/bpkg/help.cxx
+++ b/bpkg/help.cxx
@@ -51,7 +51,7 @@ namespace bpkg
     o << ""<< endl;
   }
 
-  void
+  int
   help (const help_options&, const string& t, void (*usage) (std::ostream&))
   {
     ostream& o (cout);
@@ -77,5 +77,7 @@ namespace bpkg
     else
       fail << "unknown bpkg command/help topic '" << t << "'" <<
         info << "run 'bpkg help' for more information";
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-clean b/bpkg/pkg-clean
index baed20a..1195cfe 100644
--- a/bpkg/pkg-clean
+++ b/bpkg/pkg-clean
@@ -11,10 +11,10 @@
 
 namespace bpkg
 {
-  inline void
+  inline int
   pkg_clean (const pkg_clean_options& o, cli::scanner& args)
   {
-    pkg_command ("clean", o, args);
+    return pkg_command ("clean", o, args);
   }
 }
 
diff --git a/bpkg/pkg-command b/bpkg/pkg-command
index 360a550..724caa8 100644
--- a/bpkg/pkg-command
+++ b/bpkg/pkg-command
@@ -13,7 +13,7 @@ namespace bpkg
 {
   // Common pkg-{update,clean,test,install,...} implementation.
   //
-  void
+  int
   pkg_command (const string& cmd, // Without the 'pkg-' prefix.
                const configuration_options&,
                cli::scanner& args);
diff --git a/bpkg/pkg-command.cxx b/bpkg/pkg-command.cxx
index 67ea07a..253ee66 100644
--- a/bpkg/pkg-command.cxx
+++ b/bpkg/pkg-command.cxx
@@ -39,7 +39,7 @@ namespace bpkg
     run_b (bspec);
   }
 
-  void
+  int
   pkg_command (const string& cmd,
                const configuration_options& o,
                cli::scanner& args)
@@ -75,5 +75,7 @@ namespace bpkg
     if (verb)
       text << cmd << (cmd.back () != 'e' ? "ed " : "d ")
            << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-configure b/bpkg/pkg-configure
index b042e60..df2fc40 100644
--- a/bpkg/pkg-configure
+++ b/bpkg/pkg-configure
@@ -11,7 +11,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_configure (const pkg_configure_options&, cli::scanner& args);
 
   // Configure the package, update its state, and commit the transaction.
diff --git a/bpkg/pkg-configure.cxx b/bpkg/pkg-configure.cxx
index 9e256ce..f7e1901 100644
--- a/bpkg/pkg-configure.cxx
+++ b/bpkg/pkg-configure.cxx
@@ -144,7 +144,7 @@ namespace bpkg
     t.commit ();
   }
 
-  void
+  int
   pkg_configure (const pkg_configure_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_configure");
@@ -192,5 +192,7 @@ namespace bpkg
 
     if (verb)
       text << "configured " << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-disfigure b/bpkg/pkg-disfigure
index ef78d05..2833522 100644
--- a/bpkg/pkg-disfigure
+++ b/bpkg/pkg-disfigure
@@ -11,7 +11,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_disfigure (const pkg_disfigure_options&, cli::scanner& args);
 
   // Disfigure the package, update its state, and commit the
diff --git a/bpkg/pkg-disfigure.cxx b/bpkg/pkg-disfigure.cxx
index d9e5552..465213b 100644
--- a/bpkg/pkg-disfigure.cxx
+++ b/bpkg/pkg-disfigure.cxx
@@ -127,7 +127,7 @@ namespace bpkg
     t.commit ();
   }
 
-  void
+  int
   pkg_disfigure (const pkg_disfigure_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_disfigure");
@@ -159,5 +159,7 @@ namespace bpkg
 
     if (verb)
       text << "disfigured " << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-fetch b/bpkg/pkg-fetch
index 7cfd214..d321889 100644
--- a/bpkg/pkg-fetch
+++ b/bpkg/pkg-fetch
@@ -13,7 +13,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_fetch (const pkg_fetch_options&, cli::scanner& args);
 
   // Fetch the package as an archive file and commit the transaction.
diff --git a/bpkg/pkg-fetch.cxx b/bpkg/pkg-fetch.cxx
index 9a2e84c..492c4e7 100644
--- a/bpkg/pkg-fetch.cxx
+++ b/bpkg/pkg-fetch.cxx
@@ -226,7 +226,7 @@ namespace bpkg
     return p;
   }
 
-  void
+  int
   pkg_fetch (const pkg_fetch_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_fetch");
@@ -269,5 +269,7 @@ namespace bpkg
 
     if (verb)
       text << "fetched " << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-purge b/bpkg/pkg-purge
index 0c88e19..399606d 100644
--- a/bpkg/pkg-purge
+++ b/bpkg/pkg-purge
@@ -11,7 +11,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_purge (const pkg_purge_options&, cli::scanner& args);
 
   // Remove package's filesystem objects (the source directory and, if
diff --git a/bpkg/pkg-purge.cxx b/bpkg/pkg-purge.cxx
index 47ff05f..b90136a 100644
--- a/bpkg/pkg-purge.cxx
+++ b/bpkg/pkg-purge.cxx
@@ -66,7 +66,7 @@ namespace bpkg
     }
   }
 
-  void
+  int
   pkg_purge (const pkg_purge_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_purge");
@@ -182,5 +182,7 @@ namespace bpkg
     if (verb)
         text << (o.keep () ? "keeping archive " : "purged ")
              << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-status b/bpkg/pkg-status
index 98bd014..175ea87 100644
--- a/bpkg/pkg-status
+++ b/bpkg/pkg-status
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_status (const pkg_status_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/pkg-status.cxx b/bpkg/pkg-status.cxx
index 2f0bf7f..c31e834 100644
--- a/bpkg/pkg-status.cxx
+++ b/bpkg/pkg-status.cxx
@@ -20,7 +20,7 @@ using namespace butl;
 
 namespace bpkg
 {
-  void
+  int
   pkg_status (const pkg_status_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_status");
@@ -129,5 +129,6 @@ namespace bpkg
       cout << "unknown";
 
     cout << endl;
+    return 0;
   }
 }
diff --git a/bpkg/pkg-unpack b/bpkg/pkg-unpack
index a569efe..1e5339d 100644
--- a/bpkg/pkg-unpack
+++ b/bpkg/pkg-unpack
@@ -11,7 +11,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_unpack (const pkg_unpack_options&, cli::scanner& args);
 
   // Unpack the package as a source directory and commit the transaction.
diff --git a/bpkg/pkg-unpack.cxx b/bpkg/pkg-unpack.cxx
index c224350..5af8a10 100644
--- a/bpkg/pkg-unpack.cxx
+++ b/bpkg/pkg-unpack.cxx
@@ -215,7 +215,7 @@ namespace bpkg
     return p;
   }
 
-  void
+  int
   pkg_unpack (const pkg_unpack_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_unpack");
@@ -255,5 +255,7 @@ namespace bpkg
 
     if (verb)
       text << "unpacked " << p->name << " " << p->version;
+
+    return 0;
   }
 }
diff --git a/bpkg/pkg-update b/bpkg/pkg-update
index b34e44a..a266da3 100644
--- a/bpkg/pkg-update
+++ b/bpkg/pkg-update
@@ -12,10 +12,10 @@
 
 namespace bpkg
 {
-  inline void
+  inline int
   pkg_update (const pkg_update_options& o, cli::scanner& args)
   {
-    pkg_command ("update", o, args);
+    return pkg_command ("update", o, args);
   }
 
   inline void
diff --git a/bpkg/pkg-verify b/bpkg/pkg-verify
index e0675c6..8a62b66 100644
--- a/bpkg/pkg-verify
+++ b/bpkg/pkg-verify
@@ -12,7 +12,7 @@
 
 namespace bpkg
 {
-  void
+  int
   pkg_verify (const pkg_verify_options&, cli::scanner& args);
 
   // Verify archive is a valid package and return its manifest. Throw
diff --git a/bpkg/pkg-verify.cxx b/bpkg/pkg-verify.cxx
index 969eb22..5e16410 100644
--- a/bpkg/pkg-verify.cxx
+++ b/bpkg/pkg-verify.cxx
@@ -208,7 +208,7 @@ namespace bpkg
     }
   }
 
-  void
+  int
   pkg_verify (const pkg_verify_options& o, cli::scanner& args)
   {
     tracer trace ("pkg_verify");
@@ -227,9 +227,18 @@ namespace bpkg
     // If we were asked to run silent, don't yap about the reason
     // why the package is invalid. Just return the error status.
     //
-    package_manifest m (pkg_verify (o, a, !o.silent ()));
+    try
+    {
+      package_manifest m (pkg_verify (o, a, !o.silent ()));
+
+      if (verb && !o.silent ())
+        text << "valid package " << m.name << " " << m.version;
 
-    if (verb && !o.silent ())
-      text << "valid package " << m.name << " " << m.version;
+      return 0;
+    }
+    catch (const failed&)
+    {
+      return 1;
+    }
   }
 }
diff --git a/bpkg/rep-add b/bpkg/rep-add
index 3aff082..10d85f4 100644
--- a/bpkg/rep-add
+++ b/bpkg/rep-add
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   rep_add (const rep_add_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/rep-add.cxx b/bpkg/rep-add.cxx
index bed6b86..4348206 100644
--- a/bpkg/rep-add.cxx
+++ b/bpkg/rep-add.cxx
@@ -19,7 +19,7 @@ using namespace butl;
 
 namespace bpkg
 {
-  void
+  int
   rep_add (const rep_add_options& o, cli::scanner& args)
   {
     tracer trace ("rep_add");
@@ -64,5 +64,7 @@ namespace bpkg
 
     if (verb)
       text << "added " << rn;
+
+    return 0;
   }
 }
diff --git a/bpkg/rep-create b/bpkg/rep-create
index 7ce693e..322c76c 100644
--- a/bpkg/rep-create
+++ b/bpkg/rep-create
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   rep_create (const rep_create_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/rep-create.cxx b/bpkg/rep-create.cxx
index 291374e..1f0e420 100644
--- a/bpkg/rep-create.cxx
+++ b/bpkg/rep-create.cxx
@@ -131,7 +131,7 @@ namespace bpkg
     throw failed ();
   }
 
-  void
+  int
   rep_create (const rep_create_options& o, cli::scanner& args)
   try
   {
@@ -195,9 +195,12 @@ namespace bpkg
       d.normalize ();
       text << pm.size () << " package(s) in " << d;
     }
+
+    return 0;
   }
   catch (const invalid_path& e)
   {
-    fail << "invalid path: '" << e.path () << "'";
+    error << "invalid path: '" << e.path () << "'";
+    throw failed ();
   }
 }
diff --git a/bpkg/rep-fetch b/bpkg/rep-fetch
index 9977571..9175755 100644
--- a/bpkg/rep-fetch
+++ b/bpkg/rep-fetch
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   rep_fetch (const rep_fetch_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/rep-fetch.cxx b/bpkg/rep-fetch.cxx
index 7443f56..f96607f 100644
--- a/bpkg/rep-fetch.cxx
+++ b/bpkg/rep-fetch.cxx
@@ -175,7 +175,7 @@ namespace bpkg
     db.update (r);
   }
 
-  void
+  int
   rep_fetch (const rep_fetch_options& o, cli::scanner&)
   {
     tracer trace ("rep_fetch");
@@ -239,5 +239,7 @@ namespace bpkg
 
     if (verb)
       text << pcount << " package(s) in " << rcount << " repository(s)";
+
+    return 0;
   }
 }
diff --git a/bpkg/rep-info b/bpkg/rep-info
index 8437a53..ef01369 100644
--- a/bpkg/rep-info
+++ b/bpkg/rep-info
@@ -10,7 +10,7 @@
 
 namespace bpkg
 {
-  void
+  int
   rep_info (const rep_info_options&, cli::scanner& args);
 }
 
diff --git a/bpkg/rep-info.cxx b/bpkg/rep-info.cxx
index 8bb3c7d..041d804 100644
--- a/bpkg/rep-info.cxx
+++ b/bpkg/rep-info.cxx
@@ -21,7 +21,7 @@ using namespace butl;
 
 namespace bpkg
 {
-  void
+  int
   rep_info (const rep_info_options& o, cli::scanner& args)
   {
     tracer trace ("rep_info");
@@ -108,5 +108,7 @@ namespace bpkg
     {
       fail << "unable to write to STDOUT";
     }
+
+    return 0;
   }
 }