Initial work for default update outer operation

While update still uses the old "all update rules update all their
prerequisites" assumption, test and install have been fixed not to
rely on this.

1 files changed, 14 insertions, 8 deletions

diff --git a/build2/config/init.cxx b/build2/config/init.cxx
index 2552e77..35bc94c 100644
--- a/build2/config/init.cxx
+++ b/build2/config/init.cxx
@@ -121,19 +121,25 @@ namespace build2
 
       // Register alias and fallback rule for the configure meta-operation.
       //
+      // We need this rule for out-of-any-project dependencies (e.g.,
+      // libraries imported from /usr/lib). We are registring it on the
+      // global scope similar to builtin rules.
+      //
       {
-        // We need this rule for out-of-any-project dependencies (e.g.,
-        // libraries imported from /usr/lib). Registring it on the global
-        // scope smells a bit but seems harmless.
-        //
-        rs.global ().rules.insert<mtime_target> (
+        auto& r (rs.global ().rules);
+        r.insert<mtime_target> (
           configure_id, 0, "config.file", file_rule::instance);
-
+      }
+      {
         auto& r (rs.rules);
 
-        r.insert<target> (configure_id, 0, "config", fallback_rule::instance);
-        r.insert<file> (configure_id, 0, "config.file", fallback_rule::instance);
+        //@@ outer
         r.insert<alias> (configure_id, 0, "config.alias", alias_rule::instance);
+
+        // This allows a custom configure rule while doing nothing by default.
+        //
+        r.insert<target> (configure_id, 0, "config", noop_rule::instance);
+        r.insert<file> (configure_id, 0, "config.file", noop_rule::instance);
       }
 
       return true;