v3: fix assertion evaluation and stats

Author: medvednikov

vlib/v/slow_tests/inout/v3_assert_operand_once.out

@@ -0,0 +1,4 @@
+V panic: Assertion failed...
+vlib/v/slow_tests/inout/v3_assert_operand_once.v3.v:3: assert values.pop() == 0
+   left value: values.pop() = 1
+  right value: 0

vlib/v/slow_tests/inout/v3_assert_operand_once.v3.v

@@ -0,0 +1,4 @@
+fn main() {
+	mut values := [1]
+	assert values.pop() == 0
+}

vlib/v3/gen/c/cleanc.v

@@ -191,6 +191,7 @@ mut:
 	show_test_stats                bool
 	show_test_summary              bool
 	test_run_only                  []string
+	assert_expr_overrides          map[int]string
 	print_fn_names                 []string
 	is_prod                        bool
 	check_overflow                 bool
@@ -992,6 +993,7 @@ pub fn FlatGen.new() FlatGen {
 		scope_defer_starts:              []int{}
 		fn_defers:                       []flat.NodeId{}
 		fn_defer_counts:                 map[int]string{}
+		assert_expr_overrides:           map[int]string{}
 		defer_capture_names:             []string{}
 		defer_capture_types:             map[string]types.Type{}
 		const_runtime_inits:             []string{}
@@ -12354,6 +12356,10 @@ fn (mut g FlatGen) gen_expr(id flat.NodeId) {
 		g.write('0')
 		return
 	}
+	if replacement := g.assert_expr_overrides[int(id)] {
+		g.write(replacement)
+		return
+	}
 	node := g.a.nodes[int(id)]
 	match node.kind {
 		.int_literal {

vlib/v3/gen/c/fn.v

@@ -100,6 +100,9 @@ fn (mut g FlatGen) gen_test_failure_global() {
 			g.writeln('/* V3CACHE_MODULE main */')
 		}
 		g.writeln('static int __v3_test_failures = 0;')
+		if g.show_test_stats {
+			g.writeln('static int __v3_test_assertions = 0;')
+		}
 	}
 }
 
@@ -4523,6 +4526,7 @@ fn (mut g FlatGen) gen_test_main() {
 	for idx, test_fn in tests {
 		if g.show_test_stats {
 			g.writeln('double __v3_test_start_ms_${idx} = __v3_test_now_ms();')
+			g.writeln('int __v3_test_assertions_before_${idx} = __v3_test_assertions;')
 		}
 		g.writeln('int __v3_test_failures_before_${idx} = __v3_test_failures;')
 		if hooks.before_each.len > 0 {
@@ -4538,20 +4542,19 @@ fn (mut g FlatGen) gen_test_main() {
 		}
 		if g.show_test_stats {
 			g.writeln('double __v3_test_elapsed_ms_${idx} = __v3_test_now_ms() - __v3_test_start_ms_${idx};')
+			g.writeln('int __v3_test_assertions_run_${idx} = __v3_test_assertions - __v3_test_assertions_before_${idx};')
 		}
 		if track_test_results {
 			g.writeln('if (__v3_test_failures == __v3_test_failures_before_${idx}) {')
 			g.indent++
 			g.writeln('__v3_test_passes++;')
 		}
 		if g.show_test_stats {
-			assert_count := g.test_fn_assert_count(test_fn.node_id)
-			assert_word := if assert_count == 1 { 'assert ' } else { 'asserts' }
-			g.writeln('printf("     OK    [${idx + 1}/${tests.len}] %9.3f ms     ${assert_count} ${assert_word} | main.${c_escape(test_fn.name)}()\\n", __v3_test_elapsed_ms_${idx});')
+			g.writeln('printf("     OK    [${idx + 1}/${tests.len}] %9.3f ms     %d assert%s | main.${c_escape(test_fn.name)}()\\n", __v3_test_elapsed_ms_${idx}, __v3_test_assertions_run_${idx}, __v3_test_assertions_run_${idx} == 1 ? "" : "s");')
 			g.indent--
 			g.writeln('} else {')
 			g.indent++
-			g.writeln('printf("     FAIL  [${idx + 1}/${tests.len}] %9.3f ms     ${assert_count} ${assert_word} | main.${c_escape(test_fn.name)}()\\n", __v3_test_elapsed_ms_${idx});')
+			g.writeln('printf("     FAIL  [${idx + 1}/${tests.len}] %9.3f ms     %d assert%s | main.${c_escape(test_fn.name)}()\\n", __v3_test_elapsed_ms_${idx}, __v3_test_assertions_run_${idx}, __v3_test_assertions_run_${idx} == 1 ? "" : "s");')
 		}
 		if track_test_results {
 			g.indent--
@@ -4741,23 +4744,6 @@ fn (g &FlatGen) test_fn_propagation_line(id flat.NodeId) int {
 	return 0
 }
 
-fn (g &FlatGen) test_fn_assert_count(id flat.NodeId) int {
-	if int(id) < 0 || int(id) >= g.a.nodes.len {
-		return 0
-	}
-	node := g.a.nodes[int(id)]
-	mut count := if node.kind == .assert_stmt { 1 } else { 0 }
-	for i in 0 .. node.children_count {
-		child_id := g.a.child(&node, i)
-		child := g.a.nodes[int(child_id)]
-		if child.kind in [.fn_decl, .c_fn_decl, .fn_literal] {
-			continue
-		}
-		count += g.test_fn_assert_count(child_id)
-	}
-	return count
-}
-
 fn (g &FlatGen) collect_test_harness_decl_ids(node flat.Node, mut ids []flat.NodeId) {
 	if node.kind != .file && node.kind != .block {
 		return

vlib/v3/gen/c/stmt.v

@@ -2792,15 +2792,20 @@ fn (mut g FlatGen) gen_node(id flat.NodeId) {
 			if g.is_prod {
 				return
 			}
+			condition_id := g.a.child(&node, 0)
+			captured_ids := g.gen_assert_capture_numeric_operands(condition_id)
+			if g.show_test_stats && g.test_files.len > 0 {
+				g.writeln('__v3_test_assertions++;')
+			}
 			g.write('if (!(')
-			g.gen_expr(g.a.child(&node, 0))
+			g.gen_expr(condition_id)
 			g.writeln(')) {')
 			g.indent++
 			g.writeln('v3_eprint_lit("V panic: Assertion failed...\\n");')
-			if detail := g.assert_failure_detail(node, g.a.child(&node, 0)) {
+			if detail := g.assert_failure_detail(node, condition_id) {
 				g.writeln('v3_eprint_lit("${c_escape(detail)}\\n");')
 			}
-			g.gen_assert_infix_values(g.a.child(&node, 0))
+			g.gen_assert_infix_values(condition_id)
 			if node.children_count > 1 {
 				g.write('v3_eprintln_string(')
 				g.gen_expr(g.a.child(&node, 1))
@@ -2815,6 +2820,9 @@ fn (mut g FlatGen) gen_node(id flat.NodeId) {
 			}
 			g.indent--
 			g.writeln('}')
+			for captured_id in captured_ids {
+				g.assert_expr_overrides.delete(captured_id)
+			}
 		}
 		.goto_stmt {
 			if g.gen_goto_lock_leaves(node.value) {
@@ -2926,6 +2934,36 @@ fn (mut g FlatGen) gen_assert_infix_values(condition_id flat.NodeId) {
 	g.gen_assert_numeric_value('  right value', rhs_id)
 }
 
+fn (mut g FlatGen) gen_assert_capture_numeric_operands(condition_id flat.NodeId) []int {
+	condition := g.a.node(condition_id)
+	if condition.kind != .infix || condition.children_count < 2 {
+		return []
+	}
+	mut captured_ids := []int{cap: 2}
+	for operand_index in 0 .. 2 {
+		operand_id := g.a.child(condition, operand_index)
+		node := g.a.node(operand_id)
+		if node.kind in [.int_literal, .float_literal, .char_literal] {
+			continue
+		}
+		typ := g.value_unalias_type(g.tc.resolve_type(operand_id))
+		if !typ.is_integer() && !typ.is_float() {
+			continue
+		}
+		c_type := g.value_c_type(g.tc.resolve_type(operand_id))
+		if c_type.len == 0 {
+			continue
+		}
+		tmp := g.tmp_name()
+		g.write('${c_type} ${tmp} = (${c_type})(')
+		g.gen_expr(operand_id)
+		g.writeln(');')
+		g.assert_expr_overrides[int(operand_id)] = tmp
+		captured_ids << int(operand_id)
+	}
+	return captured_ids
+}
+
 fn (mut g FlatGen) gen_assert_numeric_value(prefix string, id flat.NodeId) {
 	node := g.a.node(id)
 	label := g.assert_source_text(id)

vlib/v3/tests/test_file_harness_codegen_test.v

@@ -131,6 +131,43 @@ fn test_wait() {
 	assert !summary_line.contains('Elapsed time: 0.000 ms.'), run.output
 }
 
+fn test_v3_assertion_operands_run_once_and_stats_count_executed_assertions() {
+	run_only := os.getenv('VTEST_ONLY_FN')
+	os.unsetenv('VTEST_ONLY_FN')
+	defer {
+		if run_only.len > 0 {
+			os.setenv('VTEST_ONLY_FN', run_only, true)
+		}
+	}
+	v3_bin := build_v3()
+	failing_run := compile_and_run(v3_bin, 'assert_operand_once', '_test.v', '
+fn test_operand_once() {
+	mut values := [1]
+	assert values.pop() == 0
+}
+')
+	assert failing_run.exit_code != 0
+	assert failing_run.output.contains('left value: values.pop() = 1'), failing_run.output
+
+	stats_run := compile_and_run_with_stats(v3_bin, 'assert_runtime_count', '_test.v', 'fn helper() {
+	assert true
+}
+
+fn test_runtime_assertion_count() {
+	for _ in 0 .. 3 {
+		assert true
+	}
+	helper()
+	if false {
+		assert false
+	}
+}
+')
+	assert stats_run.exit_code == 0, stats_run.output
+	status_line := stats_run.output.split_into_lines().filter(it.contains('main.test_runtime_assertion_count()'))[0]
+	assert status_line.contains('4 asserts |'), stats_run.output
+}
+
 fn compile_project_and_run(v3_bin string, name string, files map[string]string) (os.Result, string) {
 	root := write_project(name, files)
 	return compile_project_root_and_run(v3_bin, name, root)