Add validation for --benchmark-samples to prevent crash with zero samples

Author: Chan Aung

src/catch2/internal/catch_commandline.cpp

@@ -189,6 +189,19 @@ namespace Catch {
             config.shardCount = *parsedCount;
             return ParserResult::ok( ParseResultType::Matched );
         };
+        auto const setBenchmarkSamples = [&]( std::string const& samples ) {
+        auto parsedSamples = parseUInt( samples );
+        if ( !parsedSamples ) {
+            return ParserResult::runtimeError(
+                "Could not parse '" + samples + "' as benchmark samples" );
+        }
+        if ( *parsedSamples == 0 ) {
+            return ParserResult::runtimeError(
+                "Benchmark samples must be greater than 0" );
+        }
+        config.benchmarkSamples = *parsedSamples;
+        return ParserResult::ok( ParseResultType::Matched );
+    };
 
         auto const setShardIndex = [&](std::string const& shardIndex) {
             auto parsedIndex = parseUInt( shardIndex );
@@ -281,7 +294,7 @@ namespace Catch {
             | Opt( config.skipBenchmarks)
                 ["--skip-benchmarks"]
                 ( "disable running benchmarks")
-            | Opt( config.benchmarkSamples, "samples" )
+            | Opt( setBenchmarkSamples, "samples"  )
                 ["--benchmark-samples"]
                 ( "number of samples to collect (default: 100)" )
             | Opt( config.benchmarkResamples, "resamples" )