dir: consolidate treat_path() and treat_one_path()

Commit 16e2cfa909 ("read_directory(): further split treat_path()",
2010-01-08) split treat_one_path() out of treat_path(), because
treat_leading_path() would not have access to a dirent but wanted to
re-use as much of treat_path() as possible.  Not re-using all of
treat_path() caused other bugs, as noted in commit b9670c1f5e ("dir:
fix checks on common prefix directory", 2019-12-19).  Finally, in commit
ad6f2157f9 ("dir: restructure in a way to avoid passing around a
struct dirent", 2020-01-16), dirents were removed from treat_path() and
other functions entirely.

Since the only reason for splitting these functions was the lack of a
dirent -- which no longer applies to either function -- and since the
split caused problems in the past resulting in us not using
treat_one_path() separately anymore, just undo the split.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

dir.c

@@ -1863,21 +1863,65 @@ static int resolve_dtype(int dtype, struct index_state *istate,
 	return dtype;
 }
 
-static enum path_treatment treat_one_path(struct dir_struct *dir,
+static enum path_treatment treat_path_fast(struct dir_struct *dir,
 					   struct untracked_cache_dir *untracked,
+					   struct cached_dir *cdir,
 					   struct index_state *istate,
 					   struct strbuf *path,
 					   int baselen,
-					  const struct pathspec *pathspec,
+					   const struct pathspec *pathspec)
-					  int dtype)
 {
-	int exclude;
+	strbuf_setlen(path, baselen);
-	int has_path_in_index = !!index_file_exists(istate, path->buf, path->len, ignore_case);
+	if (!cdir->ucd) {
+		strbuf_addstr(path, cdir->file);
+		return path_untracked;
+	}
+	strbuf_addstr(path, cdir->ucd->name);
+	/* treat_one_path() does this before it calls treat_directory() */
+	strbuf_complete(path, '/');
+	if (cdir->ucd->check_only)
+		/*
+		 * check_only is set as a result of treat_directory() getting
+		 * to its bottom. Verify again the same set of directories
+		 * with check_only set.
+		 */
+		return read_directory_recursive(dir, istate, path->buf, path->len,
+						cdir->ucd, 1, 0, pathspec);
+	/*
+	 * We get path_recurse in the first run when
+	 * directory_exists_in_index() returns index_nonexistent. We
+	 * are sure that new changes in the index does not impact the
+	 * outcome. Return now.
+	 */
+	return path_recurse;
+}
+
+static enum path_treatment treat_path(struct dir_struct *dir,
+				      struct untracked_cache_dir *untracked,
+				      struct cached_dir *cdir,
+				      struct index_state *istate,
+				      struct strbuf *path,
+				      int baselen,
+				      const struct pathspec *pathspec)
+{
+	int has_path_in_index, dtype, exclude;
 	enum path_treatment path_treatment;
 
-	dtype = resolve_dtype(dtype, istate, path->buf, path->len);
+	if (!cdir->d_name)
+		return treat_path_fast(dir, untracked, cdir, istate, path,
+				       baselen, pathspec);
+	if (is_dot_or_dotdot(cdir->d_name) || !fspathcmp(cdir->d_name, ".git"))
+		return path_none;
+	strbuf_setlen(path, baselen);
+	strbuf_addstr(path, cdir->d_name);
+	if (simplify_away(path->buf, path->len, pathspec))
+		return path_none;
+
+	dtype = resolve_dtype(cdir->d_type, istate, path->buf, path->len);
 
 	/* Always exclude indexed files */
+	has_path_in_index = !!index_file_exists(istate, path->buf, path->len,
+						ignore_case);
 	if (dtype != DT_DIR && has_path_in_index)
 		return path_none;
 
@@ -1942,61 +1986,6 @@ static enum path_treatment treat_one_path(struct dir_struct *dir,
 	}
 }
 
-static enum path_treatment treat_path_fast(struct dir_struct *dir,
-					   struct untracked_cache_dir *untracked,
-					   struct cached_dir *cdir,
-					   struct index_state *istate,
-					   struct strbuf *path,
-					   int baselen,
-					   const struct pathspec *pathspec)
-{
-	strbuf_setlen(path, baselen);
-	if (!cdir->ucd) {
-		strbuf_addstr(path, cdir->file);
-		return path_untracked;
-	}
-	strbuf_addstr(path, cdir->ucd->name);
-	/* treat_one_path() does this before it calls treat_directory() */
-	strbuf_complete(path, '/');
-	if (cdir->ucd->check_only)
-		/*
-		 * check_only is set as a result of treat_directory() getting
-		 * to its bottom. Verify again the same set of directories
-		 * with check_only set.
-		 */
-		return read_directory_recursive(dir, istate, path->buf, path->len,
-						cdir->ucd, 1, 0, pathspec);
-	/*
-	 * We get path_recurse in the first run when
-	 * directory_exists_in_index() returns index_nonexistent. We
-	 * are sure that new changes in the index does not impact the
-	 * outcome. Return now.
-	 */
-	return path_recurse;
-}
-
-static enum path_treatment treat_path(struct dir_struct *dir,
-				      struct untracked_cache_dir *untracked,
-				      struct cached_dir *cdir,
-				      struct index_state *istate,
-				      struct strbuf *path,
-				      int baselen,
-				      const struct pathspec *pathspec)
-{
-	if (!cdir->d_name)
-		return treat_path_fast(dir, untracked, cdir, istate, path,
-				       baselen, pathspec);
-	if (is_dot_or_dotdot(cdir->d_name) || !fspathcmp(cdir->d_name, ".git"))
-		return path_none;
-	strbuf_setlen(path, baselen);
-	strbuf_addstr(path, cdir->d_name);
-	if (simplify_away(path->buf, path->len, pathspec))
-		return path_none;
-
-	return treat_one_path(dir, untracked, istate, path, baselen, pathspec,
-			      cdir->d_type);
-}
-
 static void add_untracked(struct untracked_cache_dir *dir, const char *name)
 {
 	if (!dir)