gen.golang: add run support & testrunner

vlib/v/builder/compile.v

@@ -83,18 +83,22 @@ fn (mut b Builder) run_compiled_executable_and_exit() {
 		exit(0)
 	}
 	compiled_file := os.real_path(b.pref.out_name)
+	mut run_args := []string{cap: b.pref.run_args.len + 1}
 	run_file := if b.pref.backend.is_js() {
+		run_args << compiled_file
 		node_basename := $if windows { 'node.exe' } $else { 'node' }
 		os.find_abs_path_of_executable(node_basename) or {
-			panic('Could not find `node` in system path. Do you have Node.js installed?')
+			panic('Could not find `$node_basename` in system path. Do you have Node.js installed?')
+		}
+	} else if b.pref.backend == .golang {
+		run_args << ['run', compiled_file]
+		go_basename := $if windows { 'go.exe' } $else { 'go' }
+		os.find_abs_path_of_executable(go_basename) or {
+			panic('Could not find `$go_basename` in system path. Do you have Node.js installed?')
 		}
 	} else {
 		compiled_file
 	}
-	mut run_args := []string{cap: b.pref.run_args.len + 1}
-	if b.pref.backend.is_js() {
-		run_args << compiled_file
-	}
 	run_args << b.pref.run_args
 	mut run_process := os.new_process(run_file)
 	run_process.set_args(run_args)

vlib/v/checker/checker.v

@@ -1766,7 +1766,9 @@ fn (mut c Checker) hash_stmt(mut node ast.HashStmt) {
 		node.ct_conds = c.ct_cond_stack.clone()
 	}
 	if c.pref.backend.is_js() || c.pref.backend == .golang {
-		if !c.file.path.ends_with('.js.v') && !c.file.path.ends_with('.go.v') {
+		// consider the the best way to handle the .go.vv files
+		if !c.file.path.ends_with('.js.v') && !c.file.path.ends_with('.go.v')
+			&& !c.file.path.ends_with('.go.vv') {
 			c.error('hash statements are only allowed in backend specific files such "x.js.v" and "x.go.v"',
 				node.pos)
 		}

vlib/v/gen/golang/tests/golang_test.v

@@ -0,0 +1,94 @@
+import os
+import benchmark
+import term
+
+const is_verbose = os.getenv('VTEST_SHOW_CMD') != ''
+
+// TODO some logic copy pasted from valgrind_test.v and compiler_test.v, move to a module
+fn test_golang() {
+	$if arm64 {
+		return
+	}
+	mut bench := benchmark.new_benchmark()
+	vexe := os.getenv('VEXE')
+	vroot := os.dir(vexe)
+	dir := os.join_path(vroot, 'vlib/v/gen/golang/tests')
+	files := os.ls(dir) or { panic(err) }
+	//
+	wrkdir := os.join_path(os.temp_dir(), 'vtests', 'golang')
+	os.mkdir_all(wrkdir) or { panic(err) }
+	os.chdir(wrkdir) or {}
+	tests := files.filter(it.ends_with('.vv'))
+	if tests.len == 0 {
+		println('no golang tests found')
+		assert false
+	}
+	bench.set_total_expected_steps(tests.len)
+	for test in tests {
+		bench.step()
+		full_test_path := os.real_path(os.join_path(dir, test))
+		test_file_name := os.file_name(test)
+		relative_test_path := full_test_path.replace(vroot + '/', '')
+		work_test_path := '$wrkdir/$test_file_name'
+		go_out_test_path := '$wrkdir/${test_file_name}.go'
+		cmd := '${os.quoted_path(vexe)} -o ${os.quoted_path(go_out_test_path)} -b go ${os.quoted_path(full_test_path)}'
+		if is_verbose {
+			println(cmd)
+		}
+		res_golang := os.execute(cmd)
+		if res_golang.exit_code != 0 {
+			bench.fail()
+			eprintln(bench.step_message_fail(cmd))
+			continue
+		}
+		tmperrfile := '$dir/${test}.tmperr'
+		go_basename := $if windows { 'go.exe' } $else { 'go' }
+		res := os.execute('$go_basename run ${os.quoted_path(go_out_test_path)} 2> ${os.quoted_path(tmperrfile)}')
+		if res.exit_code != 0 {
+			bench.fail()
+			eprintln(bench.step_message_fail('$full_test_path failed to run'))
+			eprintln(res.output)
+			continue
+		}
+		mut expected := os.read_file('$dir/${test}.out') or { panic(err) }
+		errfile := '$dir/${test}.err'
+		if os.exists(errfile) {
+			mut err_expected := os.read_file('$dir/${test}.err') or { panic(err) }
+			err_expected = err_expected.trim_right('\r\n').replace('\r\n', '\n')
+			errstr := os.read_file(tmperrfile) or { panic(err) }
+			mut err_found := errstr.trim_right('\r\n').replace('\r\n', '\n')
+			if err_expected != err_found {
+				println(term.red('FAIL'))
+				println('============')
+				println('stderr expected: "$err_expected" len=$err_expected.len')
+				println('============')
+				println('stderr found:"$err_found" len=$err_found.len')
+				println('============\n')
+				bench.fail()
+				continue
+			}
+		}
+		os.rm(tmperrfile) or {}
+		expected = expected.trim_right('\r\n').replace('\r\n', '\n')
+		mut found := res.output.trim_right('\r\n').replace('\r\n', '\n')
+		found = found.trim_space()
+		if expected != found {
+			println(term.red('FAIL'))
+			println('============')
+			println('expected: "$expected" len=$expected.len')
+			println('============')
+			println('found:"$found" len=$found.len')
+			println('============\n')
+			bench.fail()
+			continue
+		}
+		bench.ok()
+		eprintln(bench.step_message_ok(relative_test_path))
+	}
+	bench.stop()
+	eprintln(term.h_divider('-'))
+	eprintln(bench.total_message('golang'))
+	if bench.nfail > 0 {
+		exit(1)
+	}
+}