cave resolve --dependencies-to-slash

Fixes: ticket:994

8 files changed, 110 insertions, 37 deletions

diff --git a/paludis/resolver/decider.cc b/paludis/resolver/decider.cc
index d68c3a9a8..bcbe09cf5 100644
--- a/paludis/resolver/decider.cc
+++ b/paludis/resolver/decider.cc
@@ -1211,22 +1211,18 @@ Decider::_add_dependencies_if_necessary(
         const std::shared_ptr<DependencyReason> reason(std::make_shared<DependencyReason>(
                     package_id, changed_choices, our_resolution->resolvent(), *s, _already_met(s->spec())));
 
+        /* empty resolvents is always ok for blockers, since blocking on things
+         * that don't exist is fine */
+        bool empty_is_ok(s->spec().if_block());
         std::shared_ptr<const Resolvents> resolvents;
 
         if (s->spec().if_package())
-            resolvents = _get_resolvents_for(*s->spec().if_package(), reason);
+            std::tie(resolvents, empty_is_ok) = _get_resolvents_for(*s->spec().if_package(), reason);
         else
             resolvents = _get_resolvents_for_blocker(*s->spec().if_block(), reason);
 
-        if (resolvents->empty())
-        {
-            if (s->spec().if_package())
-                resolvents = _get_error_resolvents_for(*s->spec().if_package(), reason);
-            else
-            {
-                /* blocking on something that doesn't exist is fine */
-            }
-        }
+        if ((! empty_is_ok) && resolvents->empty())
+            resolvents = _get_error_resolvents_for(*s->spec().if_package(), reason);
 
         for (Resolvents::ConstIterator r(resolvents->begin()), r_end(resolvents->end()) ;
                 r != r_end ; ++r)
@@ -1371,7 +1367,7 @@ Decider::find_any_score(
 
     const std::shared_ptr<DependencyReason> reason(std::make_shared<DependencyReason>(
                 our_id, make_null_shared_ptr(), our_resolution->resolvent(), dep, _already_met(dep.spec())));
-    const std::shared_ptr<const Resolvents> resolvents(_get_resolvents_for(spec, reason));
+    const std::shared_ptr<const Resolvents> resolvents(_get_resolvents_for(spec, reason).first);
 
     /* next: will already be installing */
     if (! is_block)
@@ -1491,7 +1487,7 @@ Decider::_get_destination_types_for_blocker(const BlockDepSpec & spec,
     return _imp->fns.get_destination_types_for_blocker_fn()(spec, reason);
 }
 
-const std::shared_ptr<const Resolvents>
+const std::pair<std::shared_ptr<const Resolvents>, bool>
 Decider::_get_resolvents_for(
         const PackageDepSpec & spec,
         const std::shared_ptr<const Reason> & reason) const
@@ -2005,22 +2001,18 @@ Decider::add_target_with_reason(const PackageOrBlockDepSpec & spec, const std::s
     }
     else
     {
+        /* empty resolvents is always ok for blockers, since blocking on things
+         * that don't exist is fine */
+        bool empty_is_ok(spec.if_block());
         std::shared_ptr<const Resolvents> resolvents;
 
         if (spec.if_package())
-            resolvents = _get_resolvents_for(*spec.if_package(), reason);
+            std::tie(resolvents, empty_is_ok) = _get_resolvents_for(*spec.if_package(), reason);
         else
             resolvents = _get_resolvents_for_blocker(*spec.if_block(), reason);
 
-        if (resolvents->empty())
-        {
-            if (spec.if_package())
-                resolvents = _get_error_resolvents_for(*spec.if_package(), reason);
-            else
-            {
-                /* blocking on something that doesn't exist is fine */
-            }
-        }
+        if ((! empty_is_ok) && resolvents->empty())
+            resolvents = _get_error_resolvents_for(*spec.if_package(), reason);
 
         for (Resolvents::ConstIterator r(resolvents->begin()), r_end(resolvents->end()) ;
                 r != r_end ; ++r)
diff --git a/paludis/resolver/decider.hh b/paludis/resolver/decider.hh
index e1ba60aeb..93a7a4f91 100644
--- a/paludis/resolver/decider.hh
+++ b/paludis/resolver/decider.hh
@@ -68,7 +68,7 @@ namespace paludis
                 const DestinationTypes _get_destination_types_for_blocker(const BlockDepSpec &,
                         const std::shared_ptr<const Reason> &) const;
 
-                const std::shared_ptr<const Resolvents> _get_resolvents_for(
+                const std::pair<std::shared_ptr<const Resolvents>, bool> _get_resolvents_for(
                         const PackageDepSpec & spec,
                         const std::shared_ptr<const Reason> & reason) const;
 
diff --git a/paludis/resolver/get_resolvents_for_helper.cc b/paludis/resolver/get_resolvents_for_helper.cc
index e7edcfef7..daa85dc59 100644
--- a/paludis/resolver/get_resolvents_for_helper.cc
+++ b/paludis/resolver/get_resolvents_for_helper.cc
@@ -53,6 +53,9 @@ namespace paludis
         bool want_target_dependencies;
         bool want_target_runtime_dependencies;
 
+        bool want_dependencies_on_slash;
+        bool want_runtime_dependencies_on_slash;
+
         bool want_best_slot_for_targets;
         bool want_installed_slots_for_targets;
         bool fallback_to_other_slots_for_targets;
@@ -66,6 +69,8 @@ namespace paludis
             target_destination_type(dt_install_to_slash),
             want_target_dependencies(true),
             want_target_runtime_dependencies(true),
+            want_dependencies_on_slash(true),
+            want_runtime_dependencies_on_slash(true),
             want_best_slot_for_targets(true),
             want_installed_slots_for_targets(true),
             fallback_to_other_slots_for_targets(false),
@@ -103,6 +108,18 @@ GetResolventsForHelper::set_want_target_runtime_dependencies(const bool b)
 }
 
 void
+GetResolventsForHelper::set_want_dependencies_on_slash(const bool b)
+{
+    _imp->want_dependencies_on_slash = b;
+}
+
+void
+GetResolventsForHelper::set_want_runtime_dependencies_on_slash(const bool b)
+{
+    _imp->want_runtime_dependencies_on_slash = b;
+}
+
+void
 GetResolventsForHelper::set_slots(const bool best, const bool installed, const bool fallback)
 {
     _imp->want_best_slot_otherwise = best;
@@ -125,6 +142,8 @@ namespace
         const DestinationType target_destination_type;
         const bool want_target_dependencies;
         const bool want_target_runtime_dependencies;
+        const bool want_dependencies_on_slash;
+        const bool want_runtime_dependencies_on_slash;
         const std::shared_ptr<const PackageID> package_id;
 
         DestinationTypes visit(const TargetReason &) const
@@ -149,7 +168,7 @@ namespace
 
         DestinationTypes visit(const DependencyReason & dep) const
         {
-            DestinationTypes extras;
+            DestinationTypes extras, slash;
 
             switch (target_destination_type)
             {
@@ -194,7 +213,17 @@ namespace
                     throw InternalError(PALUDIS_HERE, "unhandled dt");
             }
 
-            return extras + dt_install_to_slash;
+            if (want_runtime_dependencies_on_slash ^ want_dependencies_on_slash)
+            {
+                if (want_dependencies_on_slash && ! is_run_or_post_dep(dep.sanitised_dependency()))
+                    slash += dt_install_to_slash;
+                if (want_runtime_dependencies_on_slash && is_run_or_post_dep(dep.sanitised_dependency()))
+                    slash += dt_install_to_slash;
+            }
+            else if (want_runtime_dependencies_on_slash || want_dependencies_on_slash)
+                slash += dt_install_to_slash;
+
+            return extras | slash;
         }
 
         DestinationTypes visit(const PresetReason &) const
@@ -219,15 +248,18 @@ namespace
             const DestinationType target_destination_type,
             const bool want_target_dependencies,
             const bool want_target_runtime_dependencies,
+            const bool want_dependencies_on_slash,
+            const bool want_runtime_dependencies_on_slash,
             const std::shared_ptr<const PackageID> & package_id,
             const std::shared_ptr<const Reason> & reason)
     {
-        DestinationTypesFinder f{target_destination_type, want_target_dependencies, want_target_runtime_dependencies, package_id};
+        DestinationTypesFinder f{target_destination_type, want_target_dependencies, want_target_runtime_dependencies,
+            want_dependencies_on_slash, want_runtime_dependencies_on_slash, package_id};
         return reason->accept_returning<DestinationTypes>(f);
     }
 }
 
-std::shared_ptr<Resolvents>
+std::pair<std::shared_ptr<Resolvents>, bool>
 GetResolventsForHelper::operator() (
         const PackageDepSpec & spec,
         const std::shared_ptr<const SlotName> & maybe_slot,
@@ -284,15 +316,27 @@ GetResolventsForHelper::operator() (
     else if (want_installed)
         std::copy(installed_ids->begin(), installed_ids->end(), result_ids->back_inserter());
 
-    std::shared_ptr<Resolvents> result(std::make_shared<Resolvents>());
-    for (PackageIDSequence::ConstIterator i(result_ids->begin()), i_end(result_ids->end()) ;
-            i != i_end ; ++i)
+    std::pair<std::shared_ptr<Resolvents>, bool> result(std::make_shared<Resolvents>(), false);
+
+    if (! result_ids->empty())
     {
-        DestinationTypes destination_types(get_destination_types_for_fn(_imp->env, spec,
-                    _imp->target_destination_type, _imp->want_target_dependencies, _imp->want_target_runtime_dependencies, *i, reason));
-        for (EnumIterator<DestinationType> t, t_end(last_dt) ; t != t_end ; ++t)
-            if (destination_types[*t])
-                result->push_back(Resolvent(*i, *t));
+        result.second = true;
+
+        for (PackageIDSequence::ConstIterator i(result_ids->begin()), i_end(result_ids->end()) ;
+                i != i_end ; ++i)
+        {
+            DestinationTypes destination_types(get_destination_types_for_fn(_imp->env, spec,
+                        _imp->target_destination_type, _imp->want_target_dependencies, _imp->want_target_runtime_dependencies,
+                        _imp->want_dependencies_on_slash, _imp->want_runtime_dependencies_on_slash, *i, reason));
+
+            if (destination_types.any())
+            {
+                result.second = false;
+                for (EnumIterator<DestinationType> t, t_end(last_dt) ; t != t_end ; ++t)
+                    if (destination_types[*t])
+                        result.first->push_back(Resolvent(*i, *t));
+            }
+        }
     }
 
     return result;
diff --git a/paludis/resolver/get_resolvents_for_helper.hh b/paludis/resolver/get_resolvents_for_helper.hh
index 2ffcfd42b..03ebdef11 100644
--- a/paludis/resolver/get_resolvents_for_helper.hh
+++ b/paludis/resolver/get_resolvents_for_helper.hh
@@ -49,10 +49,13 @@ namespace paludis
                 void set_want_target_dependencies(const bool);
                 void set_want_target_runtime_dependencies(const bool);
 
+                void set_want_dependencies_on_slash(const bool);
+                void set_want_runtime_dependencies_on_slash(const bool);
+
                 void set_slots(const bool best, const bool installed, const bool fallback);
                 void set_target_slots(const bool best, const bool installed, const bool fallback);
 
-                std::shared_ptr<Resolvents> operator() (
+                std::pair<std::shared_ptr<Resolvents>, bool> operator() (
                         const PackageDepSpec &,
                         const std::shared_ptr<const SlotName> &,
                         const std::shared_ptr<const Reason> &) const;
diff --git a/paludis/resolver/resolver_functions.hh b/paludis/resolver/resolver_functions.hh
index 216ed8ce3..87b655fd9 100644
--- a/paludis/resolver/resolver_functions.hh
+++ b/paludis/resolver/resolver_functions.hh
@@ -129,7 +129,7 @@ namespace paludis
                 const Resolvent &
                 )> GetInitialConstraintsForFunction;
 
-        typedef std::function<std::shared_ptr<Resolvents> (
+        typedef std::function<std::pair<std::shared_ptr<Resolvents>, bool> (
                 const PackageDepSpec &,
                 const std::shared_ptr<const SlotName> &,
                 const std::shared_ptr<const Reason> &
diff --git a/src/clients/cave/cmd_resolve_cmdline.cc b/src/clients/cave/cmd_resolve_cmdline.cc
index e61e88ea4..8735c4f30 100644
--- a/src/clients/cave/cmd_resolve_cmdline.cc
+++ b/src/clients/cave/cmd_resolve_cmdline.cc
@@ -259,6 +259,15 @@ ResolveCommandLineResolutionOptions::ResolveCommandLineResolutionOptions(args::A
             "create a binary package and use that for the install. May be specified multiple times. If this option "
             "is not specified, a package will be built multiple times for multiple destinations"),
 #endif
+    a_dependencies_to_slash(&g_destination_options, "dependencies-to-slash", '/', "Specify what to do with "
+            "dependencies for the / filesystem when not working on /. By default, all dependencies are installed "
+            "to /.",
+            args::EnumArg::EnumArgOptions
+            ("all",                   'a',  "Send all dependencies to /")
+            ("runtime",               'r',  "Send only runtime dependencies to /")
+            ("build",                 'b',  "Send only build dependencies to /")
+            ("none",                  'n',  "Don't send dependencies to / at all"),
+            "all"),
 
 //    g_query_options(this, "Query Options", "Query the user interactively when making decisions. "
 //            "If only --query is specified, prompt for everything. Otherwise, prompt only for the specified decisions."),
diff --git a/src/clients/cave/cmd_resolve_cmdline.hh b/src/clients/cave/cmd_resolve_cmdline.hh
index 5728d011a..aa6e76f81 100644
--- a/src/clients/cave/cmd_resolve_cmdline.hh
+++ b/src/clients/cave/cmd_resolve_cmdline.hh
@@ -99,6 +99,7 @@ namespace paludis
 #ifdef ENABLE_PBINS
             args::StringSetArg a_via_binary;
 #endif
+            args::EnumArg a_dependencies_to_slash;
 
 //            args::ArgsGroup g_query_options;
 //            args::SwitchArg a_query;
diff --git a/src/clients/cave/resolve_common.cc b/src/clients/cave/resolve_common.cc
index fc902c52d..5bc23a5c8 100644
--- a/src/clients/cave/resolve_common.cc
+++ b/src/clients/cave/resolve_common.cc
@@ -788,6 +788,30 @@ paludis::cave::resolve_common(
         throw args::DoHelp("Don't understand argument '" + resolution_options.a_slots.argument() + "' to '--"
                 + resolution_options.a_slots.long_name() + "'");
 
+    if (resolution_options.a_dependencies_to_slash.argument() == "all")
+    {
+        get_resolvents_for_helper.set_want_dependencies_on_slash(true);
+        get_resolvents_for_helper.set_want_runtime_dependencies_on_slash(true);
+    }
+    else if (resolution_options.a_dependencies_to_slash.argument() == "runtime")
+    {
+        get_resolvents_for_helper.set_want_dependencies_on_slash(false);
+        get_resolvents_for_helper.set_want_runtime_dependencies_on_slash(true);
+    }
+    else if (resolution_options.a_dependencies_to_slash.argument() == "build")
+    {
+        get_resolvents_for_helper.set_want_dependencies_on_slash(true);
+        get_resolvents_for_helper.set_want_runtime_dependencies_on_slash(false);
+    }
+    else if (resolution_options.a_dependencies_to_slash.argument() == "none")
+    {
+        get_resolvents_for_helper.set_want_dependencies_on_slash(false);
+        get_resolvents_for_helper.set_want_runtime_dependencies_on_slash(false);
+    }
+    else
+        throw args::DoHelp("Don't understand argument '" + resolution_options.a_dependencies_to_slash.argument() + "' to '--"
+                + resolution_options.a_dependencies_to_slash.long_name() + "'");
+
     if (resolution_options.a_target_slots.argument() == "best-or-installed")
         get_resolvents_for_helper.set_target_slots(true, false, true);
     else if (resolution_options.a_target_slots.argument() == "installed-or-best")