From a44b937b2cf7b11b950dd8b492dcd178d47a39e0 Mon Sep 17 00:00:00 2001
From: Radoslaw Zarzynski <rzarzyns@redhat.com>
Date: Thu, 30 Jul 2020 16:41:48 +0200
Subject: [PATCH] tests: modernize all occurrences of rand_choose().

We should consider deduplication as well.

Signed-off-by: Radoslaw Zarzynski <rzarzyns@redhat.com>
---
 src/test/ObjectMap/test_object_map.cc   | 11 ++++-------
 src/test/objectstore/test_idempotent.cc | 11 ++++-------
 src/test/osd/RadosModel.h               | 11 ++++-------
 src/test/test_snap_mapper.cc            | 11 ++++-------
 src/test/xattr_bench.cc                 | 11 ++++-------
 5 files changed, 20 insertions(+), 35 deletions(-)

diff --git a/src/test/ObjectMap/test_object_map.cc b/src/test/ObjectMap/test_object_map.cc
index ad2c56e5a03c4..db19c17e8cd1e 100644
--- a/src/test/ObjectMap/test_object_map.cc
+++ b/src/test/ObjectMap/test_object_map.cc
@@ -1,4 +1,5 @@
 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+#include <iterator>
 #include <map>
 #include <set>
 #include <boost/scoped_ptr.hpp>
@@ -20,14 +21,10 @@ using namespace std;
 
 template <typename T>
 typename T::iterator rand_choose(T &cont) {
-  if (cont.size() == 0) {
-    return cont.end();
+  if (std::empty(cont)) {
+    return std::end(cont);
   }
-  int index = rand() % cont.size();
-  typename T::iterator retval = cont.begin();
-
-  for (; index > 0; --index) ++retval;
-  return retval;
+  return std::next(std::begin(cont), rand() % cont.size());
 }
 
 string num_str(unsigned i) {
diff --git a/src/test/objectstore/test_idempotent.cc b/src/test/objectstore/test_idempotent.cc
index c89ea9b70fe55..0889375ed17f0 100644
--- a/src/test/objectstore/test_idempotent.cc
+++ b/src/test/objectstore/test_idempotent.cc
@@ -13,6 +13,7 @@
  */
 
 #include <iostream>
+#include <iterator>
 #include <sstream>
 #include <boost/scoped_ptr.hpp>
 #include "os/filestore/FileStore.h"
@@ -31,14 +32,10 @@ void usage(const string &name) {
 
 template <typename T>
 typename T::iterator rand_choose(T &cont) {
-  if (cont.size() == 0) {
-    return cont.end();
+  if (std::empty(cont)) {
+    return std::end(cont);
   }
-  int index = rand() % cont.size();
-  typename T::iterator retval = cont.begin();
-
-  for (; index > 0; --index) ++retval;
-  return retval;
+  return std::next(std::begin(cont), rand() % cont.size());
 }
 
 int main(int argc, char **argv) {
diff --git a/src/test/osd/RadosModel.h b/src/test/osd/RadosModel.h
index b2e2496fd2139..d5689f6067af7 100644
--- a/src/test/osd/RadosModel.h
+++ b/src/test/osd/RadosModel.h
@@ -6,6 +6,7 @@
 #include "include/rados/librados.hpp"
 
 #include <iostream>
+#include <iterator>
 #include <sstream>
 #include <map>
 #include <set>
@@ -32,14 +33,10 @@ class TestOpStat;
 
 template <typename T>
 typename T::iterator rand_choose(T &cont) {
-  if (cont.size() == 0) {
-    return cont.end();
+  if (std::empty(cont)) {
+    return std::end(cont);
   }
-  int index = rand() % cont.size();
-  typename T::iterator retval = cont.begin();
-
-  for (; index > 0; --index) ++retval;
-  return retval;
+  return std::next(std::begin(cont), rand() % cont.size());
 }
 
 enum TestOpType {
diff --git a/src/test/test_snap_mapper.cc b/src/test/test_snap_mapper.cc
index 9b6dbdd2b0c59..50730080d8dc7 100644
--- a/src/test/test_snap_mapper.cc
+++ b/src/test/test_snap_mapper.cc
@@ -1,4 +1,5 @@
 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+#include <iterator>
 #include <map>
 #include <set>
 #include <boost/scoped_ptr.hpp>
@@ -16,14 +17,10 @@ using namespace std;
 
 template <typename T>
 typename T::iterator rand_choose(T &cont) {
-  if (cont.size() == 0) {
-    return cont.end();
+  if (std::empty(cont)) {
+    return std::end(cont);
   }
-  int index = rand() % cont.size();
-  typename T::iterator retval = cont.begin();
-
-  for (; index > 0; --index) ++retval;
-  return retval;
+  return std::next(std::begin(cont), rand() % cont.size());
 }
 
 string random_string(size_t size)
diff --git a/src/test/xattr_bench.cc b/src/test/xattr_bench.cc
index edbfae25bef89..7fac235be4916 100644
--- a/src/test/xattr_bench.cc
+++ b/src/test/xattr_bench.cc
@@ -16,6 +16,7 @@
 #include <time.h>
 #include <string.h>
 #include <iostream>
+#include <iterator>
 #include <sstream>
 #include "os/filestore/FileStore.h"
 #include "include/Context.h"
@@ -40,14 +41,10 @@ const int THREADS = 5;
 
 template <typename T>
 typename T::iterator rand_choose(T &cont) {
-  if (cont.size() == 0) {
-    return cont.end();
+  if (std::empty(cont) == 0) {
+    return std::end(cont);
   }
-  int index = rand() % cont.size();
-  typename T::iterator retval = cont.begin();
-
-  for (; index > 0; --index) ++retval;
-  return retval;
+  return std::next(std::begin(cont), rand() % cont.size());
 }
 
 class OnApplied : public Context {
-- 
2.39.5