{builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE"

Split up the "USE_THE_INDEX_COMPATIBILITY_MACROS" into that setting
and a more narrow "USE_THE_INDEX_VARIABLE". In the case of these
built-ins we only need "the_index" variable, but not the compatibility
wrapper for functions we're not using.

Let's then have some users of "USE_THE_INDEX_COMPATIBILITY_MACROS" use
this more narrow and descriptive define.

For context: The USE_THE_INDEX_COMPATIBILITY_MACROS macro was added to
test-tool.h in f8adbec (cache.h: flip
NO_THE_INDEX_COMPATIBILITY_MACROS switch, 2019-01-24).

Signed-off-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: avar

builtin/cat-file.c

@@ -3,7 +3,7 @@
  *
  * Copyright (C) Linus Torvalds, 2005
  */
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#define USE_THE_INDEX_VARIABLE
 #include "cache.h"
 #include "config.h"
 #include "builtin.h"

builtin/difftool.c

@@ -11,7 +11,7 @@
  *
  * Copyright (C) 2016 Johannes Schindelin
  */
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#define USE_THE_INDEX_VARIABLE
 #include "cache.h"
 #include "config.h"
 #include "builtin.h"

builtin/merge-tree.c

@@ -1,4 +1,4 @@
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#define USE_THE_INDEX_VARIABLE
 #include "builtin.h"
 #include "tree-walk.h"
 #include "xdiff-interface.h"

builtin/pull.c

@@ -5,7 +5,7 @@
  *
  * Fetch one or more remote refs and merge it/them into the current HEAD.
  */
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#define USE_THE_INDEX_VARIABLE
 #include "cache.h"
 #include "config.h"
 #include "builtin.h"

cache.h

@@ -433,9 +433,11 @@ typedef int (*must_prefetch_predicate)(const struct cache_entry *);
 void prefetch_cache_entries(const struct index_state *istate,
 			    must_prefetch_predicate must_prefetch);
 
-#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
+#if defined(USE_THE_INDEX_COMPATIBILITY_MACROS) || defined(USE_THE_INDEX_VARIABLE)
 extern struct index_state the_index;
 
+#ifndef USE_THE_INDEX_VARIABLE
+#ifdef USE_THE_INDEX_COMPATIBILITY_MACROS
 #define active_nr (the_index.cache_nr)
 
 #define read_cache() repo_read_index(the_repository)
@@ -447,6 +449,8 @@ extern struct index_state the_index;
 #define refresh_and_write_cache(refresh_flags, write_flags, gentle) repo_refresh_and_write_index(the_repository, (refresh_flags), (write_flags), (gentle), NULL, NULL, NULL)
 #define hold_locked_index(lock_file, flags) repo_hold_locked_index(the_repository, (lock_file), (flags))
 #endif
+#endif
+#endif
 
 #define TYPE_BITS 3
 

repository.c

@@ -2,7 +2,7 @@
  * not really _using_ the compat macros, just make sure the_index
  * declaration matches the definition in this file.
  */
-#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#define USE_THE_INDEX_VARIABLE
 #include "cache.h"
 #include "repository.h"
 #include "object-store.h"