// vtest build: !self_sandboxed_packaging? && !sanitized_job?
import os
import time
import term
import v.util.diff
import v.util.vtest

const vexe = @VEXE

const vroot = os.real_path(@VMODROOT)

const local_tdata_path = 'vlib/v/gen/c/testdata'

const testdata_folder = os.real_path(os.join_path(vroot, local_tdata_path))

const show_compilation_output = os.getenv('VTEST_SHOW_COMPILATION_OUTPUT').int() == 1

const user_os = os.user_os()

const gcc_path = os.find_abs_path_of_executable('gcc') or { '' }

fn mm(s string) string {
    return term.colorize(term.magenta, s)
}

fn mj(input ...string) string {
    return mm(input.filter(it.len > 0).join(' '))
}

fn test_out_files() {
    os.chdir(vroot) or {}
    output_path := os.join_path(os.vtmp_dir(), 'coutput_outs')
    os.mkdir_all(output_path)!
    defer {
        os.rmdir_all(output_path) or {}
    }
    files := os.ls(testdata_folder) or { [] }
    tests := files.filter(it.ends_with('.out'))
    if tests.len == 0 {
        eprintln('no `.out` tests found in ${testdata_folder}')
        return
    }
    mut total_errors := 0
    mut total_oks := 0
    mut total_oks_panic := 0
    mut total_skips := 0
    paths := vtest.filter_vtest_only(tests, basepath: testdata_folder).sorted()
    println(term.colorize(term.green,
        '> testing whether ${paths.len} .out files in ${local_tdata_path} match:'))
    for out_path in paths {
        basename, path, relpath, out_relpath := target2paths(out_path, '.out')
        if should_skip(relpath) {
            total_skips++
            continue
        }
        pexe := os.join_path(output_path, '${basename}.exe')
        //
        file_options := get_file_options(path)
        if user_os == 'windows' && file_options.vflags.contains('-cc clang') && gcc_path.len > 0
            && github_job.contains('gcc') {
            eprintln('> skipping ${relpath} on gcc-windows, since it requires clang')
            total_skips++
            continue
        }
        alloptions := '-o ${os.quoted_path(pexe)} ${file_options.vflags}'
        label := mj('v', file_options.vflags, 'run', relpath) + ' == ${mm(out_relpath)} '
        //
        compile_cmd := '${os.quoted_path(vexe)} ${alloptions} ${os.quoted_path(path)}'
        sw_compile := time.new_stopwatch()
        compilation := os.execute(compile_cmd)
        compile_ms := sw_compile.elapsed().milliseconds()
        ensure_compilation_succeeded(compilation, compile_cmd)
        //
        sw_run := time.new_stopwatch()
        res := os.execute(os.quoted_path(pexe))
        run_ms := sw_run.elapsed().milliseconds()
        //
        if res.exit_code < 0 {
            println('${term.red('FAIL')} C:${compile_ms:6}ms, R:${run_ms:2}ms ${label}')
            println('  run crashed with exit code: ${res.exit_code}')
            if res.output.len > 0 {
                println(res.output)
            }
            total_errors++
            continue
        }
        mut found := res.output.trim_right('\r\n').replace('\r\n', '\n')
        mut expected := os.read_file(out_path)!
        expected = expected.trim_right('\r\n').replace('\r\n', '\n')
        if expected.contains('================ V panic ================') {
            // panic include backtraces and absolute file paths, so can't do char by char comparison
            n_found := normalize_panic_message(found, vroot)
            n_expected := normalize_panic_message(expected, vroot)
            if found.contains('================ V panic ================') {
                if n_found.starts_with(n_expected) {
                    vprintln('${term.green('OK (panic)')} C:${compile_ms:6}ms, R:${run_ms:2}ms ${label}')
                    total_oks_panic++
                    continue
                } else {
                    // Both have panics, but there was a difference...
                    // Pass the normalized strings for further reporting.
                    // There is no point in comparing the backtraces too.
                    found = n_found
                    expected = n_expected
                }
            }
        }
        if expected != found {
            println('${term.red('FAIL')} C:${compile_ms:6}ms, R:${run_ms:2}ms ${label}')
            if diff_ := diff.compare_text(expected, found) {
                println(term.header('difference:', '-'))
                println(diff_)
            } else {
                println(term.header('expected:', '-'))
                println(expected)
                println(term.header('found:', '-'))
                println(found)
            }
            println(term.h_divider('-'))
            total_errors++
        } else {
            vprintln('${term.green('OK  ')} C:${compile_ms:6}ms, R:${run_ms:2}ms ${label}')
            total_oks++
        }
    }
    println('>>> Summary for test_out_files: files: ${paths.len}, oks: ${total_oks}, ok panics: ${total_oks_panic}, skipped: ${total_skips}, error: ${total_errors} .')
    assert total_errors == 0
}

fn test_c_must_have_files() {
    os.chdir(vroot) or {}
    output_path := os.join_path(os.vtmp_dir(), 'coutput_c_must_haves')
    os.mkdir_all(output_path)!
    defer {
        os.rmdir_all(output_path) or {}
    }
    files := os.ls(testdata_folder) or { [] }
    tests := files.filter(it.ends_with('.c.must_have'))
    if tests.len == 0 {
        eprintln('no `.c.must_have` files found in ${testdata_folder}')
        return
    }
    paths := vtest.filter_vtest_only(tests, basepath: testdata_folder).sorted()
    mut total_errors := 0
    mut total_oks := 0
    mut total_oks_panic := 0
    mut total_skips := 0
    mut failed_descriptions := []string{cap: paths.len}
    println(term.colorize(term.green,
        '> testing whether all line patterns in ${paths.len} `.c.must_have` files in ${local_tdata_path} match:'))
    for must_have_path in paths {
        basename, path, relpath, must_have_relpath := target2paths(must_have_path, '.c.must_have')
        if should_skip(relpath) {
            total_skips++
            continue
        }
        file_options := get_file_options(path)
        alloptions := '-o - ${file_options.vflags}'
        mut description := mj('v', alloptions, relpath) + ' matches ${mm(must_have_relpath)} '
        cmd := '${os.quoted_path(vexe)} ${alloptions} ${os.quoted_path(path)}'
        sw_compile := time.new_stopwatch()
        compilation := os.execute(cmd)
        compile_ms := sw_compile.elapsed().milliseconds()
        ensure_compilation_succeeded(compilation, cmd)
        expected_lines := os.read_lines(must_have_path) or { [] }
        generated_c_lines := compilation.output.split_into_lines()
        mut nmatches := 0
        mut failed_patterns := []string{}
        for idx_expected_line, eline in expected_lines {
            if does_line_match_one_of_generated_lines(eline, generated_c_lines) {
                nmatches++
                // eprintln('> testing: ${must_have_path} has line: ${eline}')
            } else {
                failed_patterns << eline
                description += '\n failed pattern: `${eline}`'
                println('${term.red('FAIL')} C:${compile_ms:5}ms ${description}')
                eprintln('${must_have_path}:${idx_expected_line + 1}: expected match error:')
                eprintln('`${cmd}` did NOT produce expected line:')
                eprintln(term.colorize(term.red, eline))
                if description !in failed_descriptions {
                    failed_descriptions << description
                }
                total_errors++
                continue
            }
        }
        if nmatches == expected_lines.len {
            vprintln('${term.green('OK  ')} C:${compile_ms:5}ms ${description}')
            total_oks++
        } else {
            if show_compilation_output {
                eprintln('> ALL lines:')
                eprintln(compilation.output)
            }
            eprintln('--------- failed patterns: -------------------------------------------')
            for fpattern in failed_patterns {
                eprintln(fpattern)
            }
            eprintln('----------------------------------------------------------------------')
        }
    }
    if failed_descriptions.len > 0 {
        eprintln('--------- failed commands: -------------------------------------------')
        for fd in failed_descriptions {
            eprintln('  > ${fd}')
        }
        eprintln('----------------------------------------------------------------------')
    }
    println('>>> Summary for test_c_must_have_files: files: ${paths.len}, oks: ${total_oks}, ok panics: ${total_oks_panic}, skipped: ${total_skips}, error: ${total_errors} .')
    assert total_errors == 0
}

fn test_or_block_err_var_collision_does_not_emit_self_referential_err() {
    os.chdir(vroot) or {}
    path := os.join_path(testdata_folder, 'or_block_err_var_collision.vv')
    cmd := '${os.quoted_path(vexe)} -o - ${os.quoted_path(path)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert !compilation.output.contains('IError err = err.err;')
    mut source_err_tmp := ''
    mut has_visible_or_block_err := false
    for line in compilation.output.split_into_lines() {
        trimmed := line.trim_space()
        if trimmed.starts_with('IError _t') && trimmed.ends_with(' = err.err;') {
            source_err_tmp = trimmed.all_after('IError ').all_before(' = err.err;')
        }
        if trimmed.starts_with('IError _t') && trimmed.contains('.err;') {
            err_tmp := trimmed.all_after('IError ').all_before(' = ')
            if compilation.output.contains('IError err = ${err_tmp};') {
                has_visible_or_block_err = true
            }
        }
    }
    assert source_err_tmp != ''
    assert !compilation.output.contains('IError err = ${source_err_tmp};')
    assert has_visible_or_block_err
}

fn test_imported_empty_interface_concat_does_not_emit_noop_array_cast_helper() {
    os.chdir(vroot) or {}
    path := os.join_path(vroot,
        'vlib/v/tests/modules/interface_array_concat_from_another_module/main_test.v')
    symbol := '__v_array_to_interface_array__Array_interface_array_concat_from_another_module__mod__Value__to__Array_interface_array_concat_from_another_module__mod__Value'
    cmd := '${os.quoted_path(vexe)} -o - ${os.quoted_path(path)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert !compilation.output.contains(symbol)
}

fn test_windows_sharedlive_string_interpolation_in_ternary_does_not_emit_inline_tmp_decl() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_live_windows_ternary_str_intp.vv')
    os.write_file(test_source,
        "module main\n\n@[live]\nfn foo(ok bool, name string) string {\n\treturn if ok { 'Hello, \${name}!' } else { '\${u32(7)}' }\n}\n\nfn main() {\n\tprintln(foo(true, 'V'))\n}\n")!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -o - -os windows -sharedlive ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    mut normalized := compilation.output.replace('\t', ' ').replace('\n', ' ')
    for normalized.contains('  ') {
        normalized = normalized.replace('  ', ' ')
    }
    assert !normalized.contains('? ( string _t')
    assert compilation.output.contains('builtin__str_intp')
}

fn test_windows_tcc_atomic_postfix_uses_interlocked_helpers() {
    os.chdir(vroot) or {}
    cc := windows_tcc_ccompiler_for_coutput_test()
    if cc == '' {
        eprintln('> skipping ${@FN} since tcc is not available on windows')
        return
    }
    test_source := os.join_path(os.vtmp_dir(), 'coutput_windows_tcc_atomic_postfix.vv')
    os.write_file(test_source, 'module main

struct App {
mut:
    idx atomic int
}

fn (mut app App) bump() {
    app.idx++
}

fn main() {
    mut app := App{}
    app.bump()
}
')!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -o - -os windows -cc ${cc} ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert compilation.output.contains('thirdparty/stdatomic/win/atomic.h')
    assert compilation.output.contains('InterlockedExchangeAdd')
    assert !compilation.output.contains('__atomic_fetch_add')
}

fn windows_tcc_ccompiler_for_coutput_test() string {
    if user_os != 'windows' {
        return 'x86_64-w64-mingw32-tcc'
    }
    bundled_tcc := os.join_path(vroot, 'thirdparty', 'tcc', 'tcc.exe')
    if os.is_file(bundled_tcc) && os.is_executable(bundled_tcc) {
        return os.quoted_path(bundled_tcc)
    }
    if os.find_abs_path_of_executable('tcc') or { '' } != '' {
        return 'tcc'
    }
    return ''
}

fn test_no_main_exports_initialize_windows_runtime() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_no_main_export_windows_init.vv')
    os.write_file(test_source,
        "module no_main\n\n@[export: 'v_sdl_app_quit']\npub fn app_quit() {}\n")!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -o - -os windows ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    generated_c_lines := compilation.output.split_into_lines()
    expected_lines := [
        'static void _vno_main_init_caller(void);',
        'static void _vno_main_cleanup_caller(void);',
        'void v_sdl_app_quit(void) {',
        '_vno_main_init_caller();',
        'void _vinit(int ___argc, voidptr ___argv) {',
        'static bool once = false; if (once) {return;} once = true;',
        'void _vcleanup(void) {',
        'static void _vno_main_cleanup_caller(void) {',
        'static void _vno_main_init_caller(void) {',
        'con_valid = AttachConsole(ATTACH_PARENT_PROCESS);',
        'err = freopen_s(&res_fp, "NUL", "w", stdout);',
        '_vinit(0,0);',
        'atexit(_vno_main_cleanup_caller);',
    ]
    for expected_line in expected_lines {
        assert does_line_match_one_of_generated_lines(expected_line, generated_c_lines)
    }
}

fn test_c_fallback_decl_uses_module_wide_c_includes() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_module_c_include')
    os.rmdir_all(test_source) or {}
    os.mkdir_all(test_source)!
    defer {
        os.rmdir_all(test_source) or {}
    }
    header_path := os.join_path(test_source, 'c_header_decl.h')
    os.write_file(header_path, 'int c_header_decl(const char* input);\n')!
    header_include_path := header_path.replace('\\', '/')
    os.write_file(os.join_path(test_source, 'include.v'), 'module main

#include "${header_include_path}"
')!
    os.write_file(os.join_path(test_source, 'decl.v'), "module main

fn C.c_header_decl(input &char) int

fn main() {
    C.c_header_decl(c'text')
}
")!
    cmd := '${os.quoted_path(vexe)} -o - ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert !compilation.output.contains('extern int c_header_decl(')
}

fn test_c_fallback_decl_uses_c_helper_submodule_includes() {
    test_source := os.join_path(os.vtmp_dir(), 'coutput_c_helper_include')
    module_path := os.join_path(test_source, 'coutput_sdl')
    c_module_path := os.join_path(module_path, 'c')
    os.rmdir_all(test_source) or {}
    os.mkdir_all(c_module_path)!
    defer {
        os.rmdir_all(test_source) or {}
    }
    header_path := os.join_path(c_module_path, 'c_helper_decl.h')
    os.write_file(header_path,
        ['#include <stdbool.h>', 'typedef enum { false_value, true_value } foreign_bool;', 'foreign_bool c_helper_decl(void);'].join('\n') +
        '\n')!
    header_include_path := header_path.replace('\\', '/')
    os.write_file(os.join_path(c_module_path, 'c.c.v'), 'module c

pub const used_import = 1

#include "${header_include_path}"
')!
    os.write_file(os.join_path(module_path, 'coutput_sdl.v'), 'module coutput_sdl

import coutput_sdl.c

pub const used_import = c.used_import
')!
    os.write_file(os.join_path(module_path, 'atomic.c.v'), 'module coutput_sdl

fn C.c_helper_decl() bool

pub fn call() {
    _ = C.c_helper_decl()
}
')!
    old_wd := os.getwd()
    os.chdir(test_source) or {}
    defer {
        os.chdir(old_wd) or {}
    }
    cmd := '${os.quoted_path(vexe)} -shared -o - coutput_sdl'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert compilation.output.contains('#include "${header_include_path}"')
    assert !compilation.output.contains('extern bool c_helper_decl(')
}

fn test_user_defined_windows_dllmain_disables_generated_entrypoint() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_user_defined_windows_dllmain.vv')
    os.write_file(test_source,
        ['module test', '', 'pub type C.DWORD = u32', 'pub type C.LPVOID = voidptr', '', 'fn C._vinit_caller()', 'fn C._vcleanup_caller()', '', "@[export: 'library_answer']", 'pub fn library_answer() int {', '\treturn 42', '}', '', "@[export: 'DllMain']", 'pub fn dll_main(hinst C.HINSTANCE, reason C.DWORD, reserved C.LPVOID) C.BOOL {', '\t_ = hinst', '\t_ = reserved', '\tif reason == C.DWORD(1) {', '\t\tC._vinit_caller()', '\t} else if reason == C.DWORD(0) {', '\t\tC._vcleanup_caller()', '\t}', '\treturn 1', '}'].join('\n') +
        '\n')!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -o - -os windows -shared -gc boehm ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    assert compilation.output.contains('void _vinit_caller() {')
    assert compilation.output.contains('GC_set_pages_executable(0);')
    assert compilation.output.contains('GC_INIT();')
    assert compilation.output.contains('DllMain(')
    assert compilation.output.contains('_vinit_caller();')
    assert compilation.output.contains('_vcleanup_caller();')
    assert !compilation.output.contains('switch (fdwReason)')
    assert !compilation.output.contains('case DLL_PROCESS_ATTACH')
}

fn test_array_sort_with_compare_uses_stable_sort_adapters() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_array_sort_with_compare_stable_sort.vv')
    source_lines := [
        'module main',
        '',
        'struct Foo {',
        '\tx int',
        '}',
        '',
        'fn by_x(a &Foo, b &Foo) int {',
        '\treturn a.x - b.x',
        '}',
        '',
        'fn main() {',
        '\tmut xs := [Foo{ x: 2 }, Foo{ x: 1 }]',
        '\txs.sort_with_compare(by_x)',
        '\tmut ys := [Foo{ x: 2 }, Foo{ x: 1 }]!',
        '\tys.sort_with_compare(by_x)',
        '\tmut zs := [Foo{ x: 2 }, Foo{ x: 1 }]',
        '\tzs.sort(a.x < b.x)',
        '}',
    ]
    os.write_file(test_source, source_lines.join('\n') + '\n')!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -o - ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    mut normalized := compilation.output.replace('\t', ' ').replace('\n', ' ')
    for normalized.contains('  ') {
        normalized = normalized.replace('  ', ' ')
    }
    assert normalized.contains('int main__by_x_qsort_adapter(const void* a, const void* b) { return main__by_x((main__Foo*)a, (main__Foo*)b); }')
    assert normalized.contains('if (xs.len > 0) { v_stable_sort(xs.data, xs.len, xs.element_size, main__by_x_qsort_adapter); }')
    assert normalized.contains('v_stable_sort(&ys, 2, sizeof(main__Foo), main__by_x_qsort_adapter);')
    assert normalized.contains('_qsort_adapter(const void* a, const void* b) { return compare_')
    assert normalized.contains('v_stable_sort(zs.data, zs.len, zs.element_size, compare_')
    assert normalized.contains('_qsort_adapter);')
}

fn test_veb_implicit_ctx_alias_uses_user_context_name() {
    os.chdir(vroot) or {}
    test_source := os.join_path(os.vtmp_dir(), 'coutput_veb_implicit_ctx_alias.vv')
    os.write_file(test_source,
        ['module main', '', 'import veb', '', 'struct App {}', '', 'struct Context {', '\tveb.Context', '}', '', 'fn (app App) nested(mut ctx Context) veb.Result {', "\treturn ctx.text('nested')", '}', '', 'fn (app App) log(_ Context) {', "\tprintln('hi')", '}', '', 'fn (app App) index(mut c Context) veb.Result {', '\tapp.log(c)', '\treturn app.nested()', '}', '', 'fn main() {', '\tmut app := App{}', '\tmut ctx := Context{}', '\t_ = app.index(mut ctx)', '}'].join('\n') +
        '\n')!
    defer {
        os.rm(test_source) or {}
    }
    cmd := '${os.quoted_path(vexe)} -gc boehm_full_opt -o - ${os.quoted_path(test_source)}'
    compilation := os.execute(cmd)
    ensure_compilation_succeeded(compilation, cmd)
    mut normalized := compilation.output.replace('\t', ' ').replace('\n', ' ')
    for normalized.contains('  ') {
        normalized = normalized.replace('  ', ' ')
    }
    assert normalized.contains('veb__Result main__App_index(main__App app, main__Context* c) { main__App_log(app, *c); GC_reachable_here(&c); return main__App_nested(app, c); }')
}

fn test_veb_implicit_ctx_alias_on_context_receiver_tmpl_not_found() {
    os.chdir(vroot) or {}
    test_dir := os.join_path(os.vtmp_dir(), 'coutput_veb_context_receiver_tmpl_not_found')
    os.rmdir_all(test_dir) or {}
    os.mkdir_all(os.join_path(test_dir, 'web'))!
    test_source := os.join_path(test_dir, 'main.v')
    os.write_file(os.join_path(test_dir, 'web', 'notfound.html'), '<h1>@ctx.req.url</h1>\n')!
    os.write_file(test_source,
        ['module main', '', 'import veb', '', 'pub struct Context {', '\tveb.Context', '}', '', 'pub struct App {}', '', 'pub fn (mut c Context) not_found() veb.Result {', '\tc.res.set_status(.not_found)', "\treturn c.html(\$tmpl('web/notfound.html'))", '}', '', 'fn main() {', '\tmut app := App{}', '\tveb.run[App, Context](mut app, 8080)', '}'].join('\n') +
        '\n')!
    defer {
        os.rmdir_all(test_dir) or {}
    }
    test_exe := os.join_path(test_dir, 'app')
    compile_cmd := '${os.quoted_path(vexe)} -gc boehm_full_opt -o ${os.quoted_path(test_exe)} ${os.quoted_path(test_source)}'
    ensure_compilation_succeeded(os.execute(compile_cmd), compile_cmd)
    c_cmd := '${os.quoted_path(vexe)} -gc boehm_full_opt -o - ${os.quoted_path(test_source)}'
    compilation := os.execute(c_cmd)
    ensure_compilation_succeeded(compilation, c_cmd)
    not_found_start := 'veb__Result main__Context_not_found(main__Context* c) {'
    assert compilation.output.contains(not_found_start)
    not_found_body :=
        compilation.output.all_after(not_found_start).all_before('VV_LOC void main__main')
    assert !not_found_body.contains('GC_reachable_here(&ctx);')
    assert not_found_body.contains('GC_reachable_here(&c);')
    assert not_found_body.contains('return veb__Context_html(&c->Context, _tmpl_res_')
}

fn test_veb_template_scope_gc_pin_does_not_escape_loop_var() {
    os.chdir(vroot) or {}
    test_dir := os.join_path(os.vtmp_dir(), 'coutput_veb_template_scope_gc_pin')
    os.rmdir_all(test_dir) or {}
    os.mkdir_all(os.join_path(test_dir, 'templates'))!
    template_lines := [
        '<div class="tree-path">',
        '  @if is_top_directory',
        '    @for i, p in ctx.parts',
        '      <a href="/@repo.user_name/@{ctx.make_path(branch_name, i)}">@p</a>',
        '    @end',
        '  @end',
        '  @if is_repo_watcher',
        '    <span>@watcher_count</span>',
        '  @end',
        '</div>',
    ]
    os.write_file(os.join_path(test_dir, 'templates', 'tree.html'),
        template_lines.join('\n') + '\n')!
    test_source := os.join_path(test_dir, 'main.v')
    source_lines := [
        'module main',
        '',
        'import veb',
        '',
        'pub struct Context {',
        '\tveb.Context',
        'pub mut:',
        '\tparts []string',
        '}',
        '',
        'pub struct App {}',
        '',
        'pub struct Repo {',
        '\tuser_name string',
        '}',
        '',
        'pub fn (ctx &Context) make_path(branch_name string, i int) string {',
        '\treturn branch_name + i.str()',
        '}',
        '',
        'pub fn (mut app App) index(mut ctx Context) veb.Result {',
        "\trepo := Repo{ user_name: 'gitly' }",
        "\tbranch_name := 'master'",
        '\tis_top_directory := true',
        '\tis_repo_watcher := false',
        '\twatcher_count := 0',
        "\treturn \$veb.html('templates/tree.html')",
        '}',
        '',
        'fn main() {',
        '\tmut app := App{}',
        "\tmut ctx := Context{ parts: ['src'] }",
        '\t_ = app.index(mut ctx)',
        '}',
    ]
    os.write_file(test_source, source_lines.join('\n') + '\n')!
    defer {
        os.rmdir_all(test_dir) or {}
    }
    test_exe := os.join_path(test_dir, 'app')
    compile_cmd := '${os.quoted_path(vexe)} -gc boehm_full_opt -o ${os.quoted_path(test_exe)} ${os.quoted_path(test_source)}'
    ensure_compilation_succeeded(os.execute(compile_cmd), compile_cmd)
    c_cmd := '${os.quoted_path(vexe)} -gc boehm_full_opt -o - ${os.quoted_path(test_source)}'
    compilation := os.execute(c_cmd)
    ensure_compilation_succeeded(compilation, c_cmd)
    index_start := 'veb__Result main__App_index(main__App* app, main__Context* ctx) {'
    assert compilation.output.contains(index_start)
    index_body := compilation.output.all_after(index_start).all_before('VV_LOC void main__main')
    assert index_body.contains('string p =')
    assert !index_body.contains('GC_reachable_here(&p);')
    assert index_body.contains('veb__Context_html(&ctx->Context, _tmpl_res_')
}

fn does_line_match_one_of_generated_lines(line string, generated_c_lines []string) bool {
    for cline in generated_c_lines {
        if line == cline {
            return true
        }
        if cline.contains(line) {
            return true
        }
    }
    return false
}

fn normalize_panic_message(message string, vroot string) string {
    mut msg := message.all_before('=========================================')
    // change windows to nix path
    s := vroot.replace(os.path_separator, '/')
    msg = msg.replace(s + '/', '')
    msg = msg.trim_space()
    return msg
}

fn vroot_relative(opath string) string {
    nvroot := vroot.replace(os.path_separator, '/') + '/'
    npath := opath.replace(os.path_separator, '/')
    return npath.replace(nvroot, '')
}

fn ensure_compilation_succeeded(compilation os.Result, cmd string) {
    if compilation.exit_code < 0 {
        eprintln('> cmd exit_code < 0, cmd: ${cmd}')
        panic(compilation.output)
    }
    if compilation.exit_code != 0 {
        eprintln('> cmd exit_code != 0, cmd: ${cmd}')
        panic('compilation failed: ${compilation.output}')
    }
}

fn target2paths(target_path string, postfix string) (string, string, string, string) {
    basename := os.file_name(target_path).replace(postfix, '')
    target_dir := os.dir(target_path)
    path := os.join_path(target_dir, '${basename}.vv')
    relpath := vroot_relative(path)
    target_relpath := vroot_relative(target_path)
    return basename, path, relpath, target_relpath
}

struct FileOptions {
mut:
    vflags string
}

pub fn get_file_options(file string) FileOptions {
    mut res := FileOptions{}
    lines := os.read_lines(file) or { [] }
    for line in lines {
        if line.starts_with('// vtest vflags:') {
            res.vflags = line.all_after(':').trim_space()
        }
    }
    return res
}

const github_job = os.getenv('GITHUB_JOB')

fn should_skip(relpath string) bool {
    if github_job.contains('musl') && relpath.ends_with('autofree_sql_or_block.vv') {
        eprintln('> skipping ${relpath} on ${github_job}, since it uses db.sqlite, and its headers are not available to the C compiler in that environment')
        return true
    }
    if github_job.contains('musl') && (relpath.ends_with('print_boehm_leak.vv')
        || relpath.ends_with('scope_cleanup_boehm_leak.vv')
        || relpath.ends_with('gc_debugger_linux.vv')) {
        eprintln('> skipping ${relpath} on ${github_job}, since gc related tests are not compatible with `-gc none`')
        return true
    }
    if user_os == 'windows' {
        if relpath.contains('_nix.vv') {
            eprintln('> skipping ${relpath} on windows')
            return true
        }
        $if !msvc {
            if relpath.contains('_msvc_windows.vv') {
                eprintln('> skipping ${relpath} on !msvc')
                return true
            }
        }
        $if !gcc {
            if relpath.contains('_gcc_windows.vv') {
                eprintln('> skipping ${relpath} on !gcc')
                return true
            }
        }
        $if msvc {
            if relpath.contains('_not_msvc_windows.vv') {
                eprintln('> skipping ${relpath} on msvc')
                return true
            }
            if relpath.ends_with('cross_printfn_v_malloc.vv') {
                eprintln('> skipping ${relpath} on msvc, since -cross -printfn does not emit a runnable executable')
                return true
            }
            if relpath.contains('asm_') {
                eprintln('> skipping ${relpath} on msvc, since it uses gcc-style inline asm')
                return true
            }
        }
    } else {
        if relpath.contains('_windows.vv') {
            eprintln('> skipping ${relpath} on !windows')
            return true
        }
    }
    if relpath.contains('freestanding_module_import_') {
        $if !amd64 {
            // https://github.com/vlang/v/issues/23397
            eprintln('> skipping ${relpath} on != amd64')
            return true
        }
        if user_os != 'linux' {
            eprintln('> skipping ${relpath} on != linux')
            return true
        }
        if gcc_path == '' {
            eprintln('> skipping ${relpath} since it needs gcc, which is not detected')
            return true
        }
    }
    if user_os == 'macos' {
        $if arm64 {
            if relpath.ends_with('spawn_stack_nix.vv') {
                eprintln('> skipping ${relpath} on macOS arm64, since i386 linking is unavailable')
                return true
            }
        }
    }
    if gcc_path == '' {
        test_path := os.join_path(vroot, relpath)
        file_options := get_file_options(test_path)
        if file_options.vflags.contains('-cc gcc') {
            eprintln('> skipping ${relpath} since its vflags require gcc, which is not detected')
            return true
        }
    }
    if github_job in ['tcc-windows', 'msvc-windows'] {
        test_path := os.join_path(vroot, relpath)
        file_options := get_file_options(test_path)
        if file_options.vflags.contains('-cc clang') {
            // The Windows runner's clang toolchain produces V binaries that
            // crash at startup on this CI; the test is still exercised by
            // the macOS/Linux jobs.
            eprintln('> skipping ${relpath} on ${github_job}, since `-cc clang` produces unstable binaries on this runner')
            return true
        }
    }
    return false
}

@[if !silent ?]
fn vprintln(msg string) {
    println(msg)
}