sparse-index: add macro for unaudited expansions

For safety, areas of code that iterate over the cache entries in the
index were guarded with ensure_full_index() and labeled with a comment.
Replace these with a macro that calls ensure_full_index_with_reason()
using the line number of the caller to help identify the situation that
is causing the index expansion.

Signed-off-by: Derrick Stolee <stolee@gmail.com>

Author: derrickstolee

Diff for: builtin/commit.c

@@ -385,7 +385,7 @@ static int list_paths(struct string_list *list, const char *with_tree,
 	}
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(the_repository->index);
+	ensure_full_index_unaudited(the_repository->index);
 	for (i = 0; i < the_repository->index->cache_nr; i++) {
 		const struct cache_entry *ce = the_repository->index->cache[i];
 		struct string_list_item *item;
@@ -1133,7 +1133,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 			int i, ita_nr = 0;
 
 			/* TODO: audit for interaction with sparse-index. */
-			ensure_full_index(the_repository->index);
+			ensure_full_index_unaudited(the_repository->index);
 			for (i = 0; i < the_repository->index->cache_nr; i++)
 				if (ce_intent_to_add(the_repository->index->cache[i]))
 					ita_nr++;

Diff for: builtin/difftool.c

@@ -592,7 +592,7 @@ static int run_dir_diff(const char *extcmd, int symlinks, const char *prefix,
 	ret = run_command(&cmd);
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(&wtindex);
+	ensure_full_index_unaudited(&wtindex);
 
 	/*
 	 * If the diff includes working copy files and those

Diff for: builtin/fsck.c

@@ -821,7 +821,7 @@ static void fsck_index(struct index_state *istate, const char *index_path,
 	unsigned int i;
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(istate);
+	ensure_full_index_unaudited(istate);
 	for (i = 0; i < istate->cache_nr; i++) {
 		unsigned int mode;
 		struct blob *blob;

Diff for: builtin/merge-index.c

@@ -66,7 +66,7 @@ static void merge_all(void)
 {
 	int i;
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(the_repository->index);
+	ensure_full_index_unaudited(the_repository->index);
 	for (i = 0; i < the_repository->index->cache_nr; i++) {
 		const struct cache_entry *ce = the_repository->index->cache[i];
 		if (!ce_stage(ce))
@@ -93,7 +93,7 @@ int cmd_merge_index(int argc,
 	repo_read_index(the_repository);
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(the_repository->index);
+	ensure_full_index_unaudited(the_repository->index);
 
 	i = 1;
 	if (!strcmp(argv[i], "-o")) {

Diff for: builtin/stash.c

@@ -1560,7 +1560,7 @@ static int do_push_stash(const struct pathspec *ps, const char *stash_msg, int q
 		char *ps_matched = xcalloc(ps->nr, 1);
 
 		/* TODO: audit for interaction with sparse-index. */
-		ensure_full_index(the_repository->index);
+		ensure_full_index_unaudited(the_repository->index);
 		for (size_t i = 0; i < the_repository->index->cache_nr; i++)
 			ce_path_match(the_repository->index, the_repository->index->cache[i], ps,
 				      ps_matched);

Diff for: builtin/submodule--helper.c

@@ -3400,7 +3400,7 @@ static void die_on_index_match(const char *path, int force)
 		char *ps_matched = xcalloc(ps.nr, 1);
 
 		/* TODO: audit for interaction with sparse-index. */
-		ensure_full_index(the_repository->index);
+		ensure_full_index_unaudited(the_repository->index);
 
 		/*
 		 * Since there is only one pathspec, we just need to

Diff for: entry.c

@@ -453,7 +453,7 @@ static void mark_colliding_entries(const struct checkout *state,
 	ce->ce_flags |= CE_MATCHED;
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(state->istate);
+	ensure_full_index_unaudited(state->istate);
 	for (size_t i = 0; i < state->istate->cache_nr; i++) {
 		struct cache_entry *dup = state->istate->cache[i];
 

Diff for: merge-recursive.c

@@ -540,7 +540,7 @@ static struct string_list *get_unmerged(struct index_state *istate)
 	string_list_init_dup(unmerged);
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(istate);
+	ensure_full_index_unaudited(istate);
 	for (i = 0; i < istate->cache_nr; i++) {
 		struct string_list_item *item;
 		struct stage_data *e;

Diff for: read-cache.c

@@ -2590,7 +2590,7 @@ int repo_index_has_changes(struct repository *repo,
 		return opt.flags.has_changes != 0;
 	} else {
 		/* TODO: audit for interaction with sparse-index. */
-		ensure_full_index(istate);
+		ensure_full_index_unaudited(istate);
 		for (i = 0; sb && i < istate->cache_nr; i++) {
 			if (i)
 				strbuf_addch(sb, ' ');
@@ -3872,7 +3872,7 @@ void overlay_tree_on_index(struct index_state *istate,
 
 	/* Hoist the unmerged entries up to stage #3 to make room */
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(istate);
+	ensure_full_index_unaudited(istate);
 	for (i = 0; i < istate->cache_nr; i++) {
 		struct cache_entry *ce = istate->cache[i];
 		if (!ce_stage(ce))

Diff for: resolve-undo.c

@@ -161,7 +161,7 @@ void unmerge_index(struct index_state *istate, const struct pathspec *pathspec,
 		return;
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(istate);
+	ensure_full_index_unaudited(istate);
 
 	for_each_string_list_item(item, istate->resolve_undo) {
 		const char *path = item->string;

Diff for: revision.c

@@ -1850,7 +1850,7 @@ static void do_add_index_objects_to_pending(struct rev_info *revs,
 	int i;
 
 	/* TODO: audit for interaction with sparse-index. */
-	ensure_full_index(istate);
+	ensure_full_index_unaudited(istate);
 	for (i = 0; i < istate->cache_nr; i++) {
 		struct cache_entry *ce = istate->cache[i];
 		struct blob *blob;

Diff for: sparse-index.h

@@ -1,6 +1,8 @@
 #ifndef SPARSE_INDEX_H__
 #define SPARSE_INDEX_H__
 
+#include "strbuf.h"
+
 /*
  * If performing an operation where the index is supposed to expand to a
  * full index, then disable the advice message by setting this global to
@@ -54,4 +56,8 @@ void ensure_full_index_with_reason(struct index_state *istate,
 				   const char *fmt,
 				   ...);
 
+#define ensure_full_index_unaudited(i) \
+	ensure_full_index_with_reason((i), \
+		"unaudited call (%s.%d)", __FILE__, __LINE__);
+
 #endif