feat(library/blast/strategies/portfolio): add 'unit' strategy for testing unit propagation

src/library/blast/strategies/portfolio.cpp

@@ -45,6 +45,12 @@ static optional<expr> apply_ematch() {
                                     ematch_action)();
 }
 
+static optional<expr> apply_unit() {
+    return mk_debug_action_strategy(unit_preprocess,
+                                    unit_propagate,
+                                    []() { return action_result::failed(); })();
+}
+
 optional<expr> apply_strategy() {
     std::string s_name(get_config().m_strategy);
     if (s_name == "preprocess") {
@@ -59,6 +65,8 @@ optional<expr> apply_strategy() {
         return apply_cc();
     } else if (s_name == "ematch") {
         return apply_ematch();
+    } else if (s_name == "unit") {
+        return apply_unit();
     } else {
         // TODO(Leo): add more builtin strategies
         return apply_simple();

tests/lean/run/blast_unit.lean

@@ -1,5 +1,5 @@
 -- Testing all possible cases of [unit_action]
-set_option blast.recursor false
+set_option blast.strategy "unit"
 variables {A₁ A₂ A₃ A₄ B₁ B₂ B₃ B₄ : Prop}
 
 -- H first, all pos

tests/lean/run/blast_unit_edges.lean

@@ -1,5 +1,6 @@
 -- Testing all possible cases of [unit_action]
-set_option blast.recursor false
+set_option blast.strategy "unit"
+
 universes l1 l2
 variables {A B C : Prop}
 variables {X : Type.{l1}} {Y : Type.{l2}}