v: skip asserts in -prod mode inside non _test.v files

vlib/v/ast/ast.v

@@ -548,6 +548,7 @@ pub:
 	bytes        int    // number of processed source code bytes
 	mod          Module // the module of the source file (from `module xyz` at the top)
 	global_scope &Scope
+	is_test      bool // true for _test.v files
 pub mut:
 	scope            &Scope
 	stmts            []Stmt            // all the statements in the source file
@@ -1245,7 +1246,8 @@ pub struct AssertStmt {
 pub:
 	pos token.Position
 pub mut:
-	expr Expr
+	expr    Expr
+	is_used bool // asserts are used in _test.v files, as well as in non -prod builds of all files
 }
 
 // `if [x := opt()] {`

vlib/v/gen/c/assert.v

@@ -6,6 +6,9 @@ module c
 import v.ast
 
 fn (mut g Gen) gen_assert_stmt(original_assert_statement ast.AssertStmt) {
+	if !original_assert_statement.is_used {
+		return
+	}
 	mut node := original_assert_statement
 	g.writeln('// assert')
 	if mut node.expr is ast.InfixExpr {

vlib/v/gen/js/js.v

@@ -613,6 +613,9 @@ fn (mut g JsGen) expr(node ast.Expr) {
 
 // TODO
 fn (mut g JsGen) gen_assert_stmt(a ast.AssertStmt) {
+	if !a.is_used {
+		return
+	}
 	g.writeln('// assert')
 	g.write('if( ')
 	g.expr(a.expr)

vlib/v/markused/walker.v

@@ -54,8 +54,10 @@ pub fn (mut w Walker) stmt(node ast.Stmt) {
 			w.asm_io(node.input)
 		}
 		ast.AssertStmt {
-			w.expr(node.expr)
-			w.n_asserts++
+			if node.is_used {
+				w.expr(node.expr)
+				w.n_asserts++
+			}
 		}
 		ast.AssignStmt {
 			w.exprs(node.left)

vlib/v/parser/parser.v

@@ -31,6 +31,7 @@ mut:
 	peek_tok            token.Token
 	table               &ast.Table
 	language            ast.Language
+	inside_test_file    bool // when inside _test.v or _test.vv file
 	inside_if           bool
 	inside_if_expr      bool
 	inside_ct_if_expr   bool
@@ -79,6 +80,7 @@ mut:
 pub fn parse_stmt(text string, table &ast.Table, scope &ast.Scope) ast.Stmt {
 	mut p := Parser{
 		scanner: scanner.new_scanner(text, .skip_comments, &pref.Preferences{})
+		inside_test_file: true
 		table: table
 		pref: &pref.Preferences{}
 		scope: scope
@@ -138,6 +140,9 @@ pub fn (mut p Parser) set_path(path string) {
 	p.file_name = path
 	p.file_base = os.base(path)
 	p.file_name_dir = os.dir(path)
+	if p.file_base.ends_with('_test.v') || p.file_base.ends_with('_test.vv') {
+		p.inside_test_file = true
+	}
 	before_dot_v := path.before('.v') // also works for .vv and .vsh
 	language := before_dot_v.all_after_last('.')
 	langauge_with_underscore := before_dot_v.all_after_last('_')
@@ -276,6 +281,7 @@ pub fn (mut p Parser) parse() ast.File {
 	return ast.File{
 		path: p.file_name
 		path_base: p.file_base
+		is_test: p.inside_test_file
 		lines: p.scanner.line_nr
 		bytes: p.scanner.text.len
 		mod: module_decl
@@ -686,6 +692,7 @@ pub fn (mut p Parser) stmt(is_top_level bool) ast.Stmt {
 			return ast.AssertStmt{
 				expr: expr
 				pos: pos
+				is_used: p.inside_test_file || !p.pref.is_prod
 			}
 		}
 		.key_for {

vlib/v/tests/prod/asserts_should_be_skipped.prod.v

@@ -0,0 +1,4 @@
+fn main() {
+	assert 1 > 2
+	println('finished')
+}

vlib/v/tests/prod/asserts_should_be_skipped.prod.v.expected.txt

@@ -0,0 +1 @@
+finished

vlib/v/tests/repl/runner/runner.v

@@ -41,7 +41,7 @@ fn diff_files(file_result string, file_expected string) string {
 
 pub fn run_repl_file(wd string, vexec string, file string) ?string {
 	vexec_folder := os.dir(vexec) + os.path_separator
-	fcontent := os.read_file(file) or { return error('Could not read file $file') }
+	fcontent := os.read_file(file) or { return error('Could not read repl file $file') }
 	content := fcontent.replace('\r', '')
 	input := content.all_before('===output===\n')
 	output := content.all_after('===output===\n').trim_right('\n\r')
@@ -81,7 +81,7 @@ $diff
 pub fn run_prod_file(wd string, vexec string, file string) ?string {
 	file_expected := '${file}.expected.txt'
 	f_expected_content := os.read_file(file_expected) or {
-		return error('Could not read file $file')
+		return error('Could not read expected prod file $file_expected')
 	}
 	expected_content := f_expected_content.replace('\r', '')
 	cmd := '"$vexec" -prod run "$file"'