Add support for config.cli=false (leave unconfigured)

2 files changed, 12 insertions, 4 deletions

diff --git a/build2/config/utility b/build2/config/utility
index de75de4..31270fb 100644
--- a/build2/config/utility
+++ b/build2/config/utility
@@ -120,9 +120,9 @@ namespace build2
 
     // Set the config.*.configured value. Note that you only need to set it to
     // false. It will be automatically ignored if there are any other config.*
-    // values for this module.
+    // values for this module. Return true if this sets a new value.
     //
-    void
+    bool
     unconfigured (scope& root, const string& ns, bool);
 
     // Enter the variable so that it is saved during configuration. See
diff --git a/build2/config/utility.cxx b/build2/config/utility.cxx
index 9131620..4c0e933 100644
--- a/build2/config/utility.cxx
+++ b/build2/config/utility.cxx
@@ -105,7 +105,7 @@ namespace build2
       return l && !cast<bool> (l);
     }
 
-    void
+    bool
     unconfigured (scope& root, const string& ns, bool v)
     {
       // Note: not overridable.
@@ -115,7 +115,15 @@ namespace build2
       if (current_mif->id == configure_id)
         save_variable (root, var);
 
-      root.assign (var) = !v;
+      value& x (root.assign (var));
+
+      if (x.null || cast<bool> (x) != !v)
+      {
+        x = !v;
+        return true;
+      }
+      else
+        return false;
     }
 
     void