Adding local forking executor and associated tests

tests/unit_executor_forkingexecutor.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+
+#include "daggy/executors/ForkingExecutor.hpp"
+
+#include "catch.hpp"
+
+TEST_CASE("Basic Execution", "[forking_executor]") {
+  daggy::executor::ForkingExecutor ex;
+
+  SECTION("Simple Run") {
+    std::vector<std::string> cmd{"/usr/bin/echo", "abc", "123"};
+
+    auto rec = ex.runCommand(cmd);
+
+    REQUIRE(rec.rc == 0);
+    REQUIRE(rec.output == "abc 123\n");
+    REQUIRE(rec.error.empty());
+  }
+
+  SECTION("Error Run") {
+    std::vector<std::string> cmd{"/usr/bin/expr", "1", "+", "+"};
+
+    auto rec = ex.runCommand(cmd);
+
+    REQUIRE(rec.rc == 2);
+    REQUIRE(rec.error == "/usr/bin/expr: syntax error: missing argument after ‘+’\n");
+    REQUIRE(rec.output.empty());
+  }
+}