Threads tests WIP

tests/testdata/cpp/simple/.gitignore

@@ -2,3 +2,4 @@ simple
 variables
 struct
 printer
+threads

tests/testdata/cpp/simple/.ycm_extra_conf.py

@@ -2,6 +2,7 @@ def Settings( **kwargs ):
   return {
     'flags': [
       '-x', 'c++',
+      '-std=c++17',
       '-Wextra', '-Werror', '-Wall'
     ]
   }

tests/testdata/cpp/simple/Makefile

@@ -2,7 +2,7 @@ CXXFLAGS=-g -O0 -std=c++17
 
 .PHONY: all
 
-TARGETS=simple variables struct printer
+TARGETS=simple variables struct printer threads
 
 all: $(TARGETS)
 

tests/testdata/cpp/simple/threads.cpp

@@ -0,0 +1,57 @@
+#include <chrono>
+#include <cstdlib>
+#include <iostream>
+#include <string_view>
+#include <system_error>
+#include <thread>
+#include <vector>
+#include <charconv>
+#include <random>
+
+int main( int argc, char ** argv )
+{
+  int numThreads = {};
+  if ( argc < 2 )
+  {
+    numThreads = 5;
+  }
+  else
+  {
+    std::string_view numThreadArg( argv[ 1 ] );
+    if ( auto [ p, ec ] = std::from_chars( numThreadArg.begin(),
+                                           numThreadArg.end(),
+                                           numThreads );
+         ec != std::errc() )
+    {
+      std::cerr << "Usage " << argv[ 0 ] << " <number of threads>\n";
+      return 2;
+    }
+  }
+
+  std::cout << "Creating " << numThreads << " threads" << '\n';
+
+  std::vector<std::thread> threads{};
+  threads.reserve( numThreads );
+
+  auto eng = std::default_random_engine() ;
+  auto dist = std::uniform_int_distribution<int>( 250, 1000 );
+
+  for ( int i = 0; i < numThreads; ++i )
+  {
+    using namespace std::chrono_literals;
+    threads.emplace_back( [&,tnum=i]() {
+      std::cout << "Started thread " << tnum << '\n';
+      std::this_thread::sleep_for(
+        5s + std::chrono::milliseconds( dist( eng ) ) );
+      std::cout << "Completed thread " << tnum << '\n';
+    });
+  }
+
+
+  for ( int i = 0; i < numThreads; ++i )
+  {
+    threads[ i ].join();
+  }
+
+  return 0;
+}