bug#48264: [PATCH v3 06/15] Rearrange set_internal for buffer forwarded symbols

[Spencer Baugh]

Previously, when setting buffer-local values for DEFVAR_PER_BUFFER
variables, the call to SET_PER_BUFFER_VALUE_P was far from the call to
set_per_buffer_value, even though they're conceptually tied together.

Now, the two calls are in the same place in store_symval_forwarding,
and we can delete the old call to SET_PER_BUFFER_VALUE_P in
set_internal.

Since we did this, we need to also avoid calling
store_symval_forwarding in set_internal when setting the default value
for a DEFVAR_PER_BUFFER variable.

This improves clarity quite a bit; it also makes it easier to later
merge set_per_buffer_value and SET_PER_BUFFER_VALUE_P together.

* src/data.c (store_symval_forwarding):
Call SET_PER_BUFFER_VALUE_P directly for buffer-forwarded symbols.
(set_internal):
Don't call SET_PER_BUFFER_VALUE_P for buffer-forwarded symbols.  Also
don't call store_symval_forwarding when we're setting the default
value for a buffer-forwarded symbol.
---
 src/data.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/data.c b/src/data.c
index 75ebcceb93..b3d3111eaa 100644
--- a/src/data.c
+++ b/src/data.c
@@ -1320,6 +1320,9 @@ store_symval_forwarding (lispfwd valcontents, Lisp_Object 
newval,
        if (buf == NULL)
          buf = current_buffer;
        set_per_buffer_value (buf, offset, newval);
+        int idx = PER_BUFFER_IDX (offset);
+        if (idx > 0)
+          SET_PER_BUFFER_VALUE_P (buf, idx, 1);
       }
       break;
 
@@ -1593,17 +1596,16 @@ set_internal (Lisp_Object symbol, Lisp_Object newval, 
Lisp_Object where,
        struct buffer *buf
          = BUFFERP (where) ? XBUFFER (where) : current_buffer;
        lispfwd innercontents = SYMBOL_FWD (sym);
+        bool should_store = true;
        if (BUFFER_OBJFWDP (innercontents))
          {
            int offset = XBUFFER_OBJFWD (innercontents)->offset;
-           int idx = PER_BUFFER_IDX (offset);
            if (bindflag == SET_INTERNAL_SET
-               && !PER_BUFFER_VALUE_P (buf, offset))
+               && !PER_BUFFER_VALUE_P (buf, offset)
+                && let_shadows_buffer_binding_p (sym))
              {
-               if (let_shadows_buffer_binding_p (sym))
-                 set_default_internal (symbol, newval, bindflag);
-               else
-                 SET_PER_BUFFER_VALUE_P (buf, idx, 1);
+                set_default_internal (symbol, newval, bindflag);
+               should_store = false;
              }
          }
 
@@ -1613,7 +1615,7 @@ set_internal (Lisp_Object symbol, Lisp_Object newval, 
Lisp_Object where,
            sym->u.s.redirect = SYMBOL_PLAINVAL;
            SET_SYMBOL_VAL (sym, newval);
          }
-       else
+       else if (should_store)
          store_symval_forwarding (/* sym, */ innercontents, newval, buf);
        break;
       }
-- 
2.31.1