From cd49acc1cf54078d1d682fdb326d4411f4de661c Mon Sep 17 00:00:00 2001
From: Martino Luca <martinoluca@fb.com>
Date: Thu, 14 Dec 2017 07:00:33 -0800
Subject: [PATCH] Refactor directory traversal into its own utility function

Reviewed By: mbouaziz

Differential Revision: D6533384

fbshipit-source-id: 4d05b16
---
 infer/src/base/Utils.ml                    | 18 ++++++++++++++++++
 infer/src/base/Utils.mli                   |  3 +++
 infer/src/clang/cFrontend_checkers_main.ml | 18 +++---------------
 3 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/infer/src/base/Utils.ml b/infer/src/base/Utils.ml
index 5eddbd5b9..087fe2743 100644
--- a/infer/src/base/Utils.ml
+++ b/infer/src/base/Utils.ml
@@ -16,6 +16,24 @@ module L = Die
 (** initial process times *)
 let initial_times = Unix.times ()
 
+(** recursively traverse a path for files ending with a given extension *)
+let find_files ~path ~extension =
+  let rec traverse_dir_aux init dir_path =
+    let aux base_path files rel_path =
+      let full_path = base_path ^/ rel_path in
+      match (Unix.stat full_path).Unix.st_kind with
+      | Unix.S_REG when String.is_suffix ~suffix:extension full_path ->
+          full_path :: files
+      | Unix.S_DIR ->
+          traverse_dir_aux files full_path
+      | _ ->
+          files
+    in
+    Sys.fold_dir ~init ~f:(aux dir_path) dir_path
+  in
+  traverse_dir_aux [] path
+
+
 (** read a source file and return a list of lines, or None in case of error *)
 let read_file fname =
   let res = ref [] in
diff --git a/infer/src/base/Utils.mli b/infer/src/base/Utils.mli
index af9d49710..178879626 100644
--- a/infer/src/base/Utils.mli
+++ b/infer/src/base/Utils.mli
@@ -13,6 +13,9 @@ open! IStd
 val initial_times : Unix.process_times
 (** initial process times *)
 
+val find_files : path:string -> extension:string -> string list
+(** recursively traverse a path for files ending with a given extension *)
+
 val string_crc_hex32 : string -> string
 (** Compute a 32-character hexadecimal crc using the Digest module  *)
 
diff --git a/infer/src/clang/cFrontend_checkers_main.ml b/infer/src/clang/cFrontend_checkers_main.ml
index 6babc782b..d1c15075a 100644
--- a/infer/src/clang/cFrontend_checkers_main.ml
+++ b/infer/src/clang/cFrontend_checkers_main.ml
@@ -355,20 +355,9 @@ let store_issues source_file =
 
 
 let find_linters_files () =
-  let rec find_aux init dir_path =
-    let aux base_path files rel_path =
-      let full_path = Filename.concat base_path rel_path in
-      match (Unix.stat full_path).Unix.st_kind with
-      | Unix.S_REG when String.is_suffix ~suffix:".al" full_path ->
-          full_path :: files
-      | Unix.S_DIR ->
-          find_aux files full_path
-      | _ ->
-          files
-    in
-    Sys.fold_dir ~init ~f:(aux dir_path) dir_path
-  in
-  List.concat (List.map ~f:(fun folder -> find_aux [] folder) Config.linters_def_folder)
+  List.concat_map
+    ~f:(fun folder -> Utils.find_files ~path:folder ~extension:".al")
+    Config.linters_def_folder
 
 
 let linters_files =
@@ -410,4 +399,3 @@ let do_frontend_checks (trans_unit_ctx: CFrontend_config.translation_unit_contex
         Tableaux.print_global_valuation_map ()) *)
   | _ (* NOTE: Assumes that an AST always starts with a TranslationUnitDecl *) ->
       assert false
-