srv test: do 100 pulls twice and compare list

The previous implementation was still a bit unstable in terms of failing
at times. Lets try if we have more luck with this one.

Git-Dch: Ignore

apt-pkg/contrib/srvrec.h

@@ -12,6 +12,7 @@
 #include <arpa/nameser.h>
 #include <vector>
 #include <string>
+#include <tuple>
 
 class SrvRec
 {
@@ -29,6 +30,9 @@ class SrvRec
    bool operator<(SrvRec const &other) const {
       return this->priority < other.priority;
    }
+   bool operator==(SrvRec const &other) const {
+      return std::tie(target, priority, weight, port) == std::tie(other.target, other.priority, other.weight, other.port);
+   }
 
    SrvRec(std::string const Target, u_int16_t const Priority,
 	 u_int16_t const Weight, u_int16_t const Port) :

test/libapt/srvrecs_test.cc

@@ -1,41 +1,75 @@
 #include <config.h>
 
 #include <apt-pkg/srvrec.h>
+#include <apt-pkg/strutl.h>
 
-#include <string>
+#include <algorithm>
 #include <iostream>
+#include <string>
 
 #include <gtest/gtest.h>
 
 TEST(SrvRecTest, PopFromSrvRecs)
 {
-   // the PopFromSrvRecs() is using a random number so we must
-   // run it a bunch of times to ensure we are not fooled by randomness
-   std::set<std::string> selected;
-   for(size_t i = 0; i < 100; ++i)
+   std::vector<SrvRec> Meep;
+   Meep.emplace_back("foo", 20, 0, 80);
+   Meep.emplace_back("bar", 20, 0, 80);
+   Meep.emplace_back("baz", 30, 0, 80);
+
+   EXPECT_EQ(Meep.size(), 3);
+   SrvRec const result = PopFromSrvRecs(Meep);
+   // ensure that pop removed one element
+   EXPECT_EQ(Meep.size(), 2);
+   EXPECT_NE(result.target, "baz");
+
+   SrvRec const result2 = PopFromSrvRecs(Meep);
+   EXPECT_NE(result.target, result2.target);
+   EXPECT_NE(result2.target, "baz");
+   EXPECT_EQ(Meep.size(), 1);
+
+   SrvRec const result3 = PopFromSrvRecs(Meep);
+   EXPECT_EQ(result3.target, "baz");
+   EXPECT_TRUE(Meep.empty());
+}
+
+TEST(SrvRecTest,Randomness)
+{
+   constexpr unsigned int testLength = 100;
+   std::vector<SrvRec> base1;
+   std::vector<SrvRec> base2;
+   std::vector<SrvRec> base3;
+   for (unsigned int i = 0; i < testLength; ++i)
    {
-      std::vector<SrvRec> Meep;
-      Meep.emplace_back("foo", 20, 0, 80);
-      Meep.emplace_back("bar", 20, 0, 80);
-      Meep.emplace_back("baz", 30, 0, 80);
-
-      EXPECT_EQ(Meep.size(), 3);
-      SrvRec const result = PopFromSrvRecs(Meep);
-      selected.insert(result.target);
-      // ensure that pop removed one element
-      EXPECT_EQ(Meep.size(), 2);
-      EXPECT_NE(result.target, "baz");
-
-      SrvRec const result2 = PopFromSrvRecs(Meep);
-      EXPECT_NE(result.target, result2.target);
-      EXPECT_NE(result2.target, "baz");
-      EXPECT_EQ(Meep.size(), 1);
-
-      SrvRec const result3 = PopFromSrvRecs(Meep);
-      EXPECT_EQ(result3.target, "baz");
-      EXPECT_TRUE(Meep.empty());
+      std::string name;
+      strprintf(name, "foo%d", i);
+      base1.emplace_back(name, 20, 0, 80);
+      base2.emplace_back(name, 20, 0, 80);
+      base3.emplace_back(name, 30, 0, 80);
    }
+   EXPECT_EQ(testLength, base1.size());
+   EXPECT_EQ(testLength, base2.size());
+   EXPECT_EQ(testLength, base3.size());
+   std::move(base3.begin(), base3.end(), std::back_inserter(base2));
+   EXPECT_EQ(testLength*2, base2.size());
+
+   std::vector<SrvRec> first_pull;
+   for (unsigned int i = 0; i < testLength; ++i)
+      first_pull.push_back(PopFromSrvRecs(base1));
+   EXPECT_TRUE(base1.empty());
+   EXPECT_FALSE(first_pull.empty());
+   EXPECT_EQ(testLength, first_pull.size());
+
+   std::vector<SrvRec> second_pull;
+   for (unsigned int i = 0; i < testLength; ++i)
+      second_pull.push_back(PopFromSrvRecs(base2));
+   EXPECT_FALSE(base2.empty());
+   EXPECT_FALSE(second_pull.empty());
+   EXPECT_EQ(testLength, second_pull.size());
+
+   EXPECT_EQ(first_pull.size(), second_pull.size());
+   EXPECT_TRUE(std::all_of(first_pull.begin(), first_pull.end(), [](SrvRec const &R) { return R.priority == 20; }));
+   EXPECT_TRUE(std::all_of(second_pull.begin(), second_pull.end(), [](SrvRec const &R) { return R.priority == 20; }));
+   EXPECT_FALSE(std::equal(first_pull.begin(), first_pull.end(), second_pull.begin()));
 
-   // ensure that after enough runs we end up with both selected
-   EXPECT_EQ(selected.size(), 2);
+   EXPECT_TRUE(std::all_of(base2.begin(), base2.end(), [](SrvRec const &R) { return R.priority == 30; }));
 }