More Lua test porting

Mostly relatively boring, some things to note here:

 - Our UTF-8 spec tests only covers the Lua 5.3 tests. We don't support
   5.4's lax mode yet.

 - I've ported some coroutine tests but am keeping our original ones
   around for now, as they're slightly more advanced (we also test
   suspending), but probably could de-duplicate in the future.

 - Lots of tests I'm very unsure about here (especially in varargs and
   locals). I suspect some of these were for very specific cases in the
   VM which no longer make any sense.

src/main/java/org/squiddev/cobalt/lib/Utf8Lib.java

@@ -85,8 +85,8 @@ private static Varargs codepoint(LuaState state, Varargs args) throws LuaError {
 		int i = posRelative(args.arg(2).optInteger(1), length);
 		int j = posRelative(args.arg(3).optInteger(i), length);
 
-		if (i < 1) throw ErrorFactory.argError(2, "out of range");
-		if (j > length) throw ErrorFactory.argError(3, "out of range");
+		if (i < 1) throw ErrorFactory.argError(2, "out of bounds");
+		if (j > length) throw ErrorFactory.argError(3, "out of bounds");
 		if (i > j) return NONE;
 
 		IntBuffer off = new IntBuffer();
@@ -115,7 +115,7 @@ private static Varargs len(LuaState state, Varargs args) throws LuaError {
 		IntBuffer offset = new IntBuffer();
 		while (i <= j) {
 			long codepoint = decodeUtf8(s, i, offset);
-			if (codepoint < 0) return varargsOf(Constants.FALSE, valueOf(i + 1));
+			if (codepoint < 0) return varargsOf(NIL, valueOf(i + 1));
 
 			n++;
 			i += offset.value;
@@ -131,7 +131,7 @@ private static LuaValue offset(LuaState state, LuaValue arg1, LuaValue arg2, Lua
 		int length = s.length();
 		int position = (n >= 0) ? 1 : length + 1;
 		position = posRelative(arg3.optInteger(position), length) - 1;
-		if (position < 0 || position > length) throw ErrorFactory.argError(3, "position out of range");
+		if (position < 0 || position > length) throw ErrorFactory.argError(3, "position out of bounds");
 
 		if (n == 0) {
 			while (position > 0 && isCont(s, position)) position--;

src/test/java/org/squiddev/cobalt/AssertTests.java

@@ -90,7 +90,6 @@ public void main(String name) throws IOException, CompileException, LuaError, In
 		"nextvar",
 		"pm",
 		"sort",
-		"vararg",
 		"verybig",
 	})
 	public void lua51(String name) throws Exception {
@@ -112,7 +111,6 @@ public void lua51(String name) throws Exception {
 		"db",
 		"nextvar",
 		"tpack",
-		"utf8",
 	})
 	public void lua53(String name) throws Exception {
 		ScriptHelper helpers = new ScriptHelper("/assert/lua5.3/");

src/test/java/org/squiddev/cobalt/LuaSpecTest.java

@@ -1,7 +1,6 @@
 package org.squiddev.cobalt;
 
 import org.junit.jupiter.api.*;
-import org.opentest4j.TestAbortedException;
 import org.squiddev.cobalt.compiler.CompileException;
 import org.squiddev.cobalt.compiler.LoadState;
 import org.squiddev.cobalt.debug.DebugHelpers;
@@ -19,17 +18,21 @@
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 public class LuaSpecTest {
 	private static final Path ROOT = Path.of("src", "test", "resources", "spec");
+	private static final Pattern TAG = Pattern.compile(":([^ ]+)");
 	private final LuaState state;
 	private final LuaTable env;
 
 	private List<DynamicNode> nodes;
 
 	private static String stripTags(String name) {
-		return name.replaceAll(" +:[^ ]+", "");
+		return TAG.matcher(name).replaceAll("");
 	}
 
 	public LuaSpecTest() throws IOException, LuaError, CompileException {
@@ -40,6 +43,9 @@ public LuaSpecTest() throws IOException, LuaError, CompileException {
 		Bit32Lib.add(state, env);
 		TestLib.add(env);
 
+		// Set the "arg" global as we've have some tests which need it.
+		env.rawset("arg", new LuaTable());
+
 		try (InputStream is = new BufferedInputStream(Files.newInputStream(ROOT.resolve("_prelude.lua")))) {
 			var expect = LoadState.load(state, is, "@_prelude.lua", env);
 			LuaThread.runMain(state, expect);
@@ -101,8 +107,19 @@ public LuaSpecTest() throws IOException, LuaError, CompileException {
 		}).create());
 	}
 
+	private static boolean checkTags(String name) {
+		var matcher = TAG.matcher(name);
+		while (matcher.find()) {
+			var tag = matcher.group(1);
+			if (tag.equals("cobalt") || tag.startsWith("lua")) continue;
+			if (tag.equals("!cobalt")) return false;
+			throw new IllegalStateException("Unknown tag " + tag);
+		}
+		return true;
+	}
+
 	private static DynamicNode filterNode(String name, DynamicNode node) {
-		return name.contains(":!cobalt") ? makePending(node) : node;
+		return checkTags(name) ? node : makePending(node);
 	}
 
 	private static DynamicNode makePending(DynamicNode node) {
@@ -117,7 +134,7 @@ private static DynamicNode makePending(DynamicNode node) {
 				test.getDisplayName(),
 				test.getTestSourceUri().orElse(null),
 				() -> {
-					throw new TestAbortedException("Not run on Cobalt");
+					assertThrows(Throwable.class, test.getExecutable(), "Test is marked :!cobalt, but passes on Cobalt.");
 				}
 			);
 		} else {

src/test/resources/assert/lua5.1/closure.lua

@@ -160,24 +160,6 @@ local running, main_thread = coroutine.running()
 assert(running ~= nil and main_thread)
 
 
--- tests for global environment
-
-local function foo (a)
-  setfenv(0, a)
-  coroutine.yield(getfenv())
-  assert(getfenv(0) == a)
-  assert(getfenv(1) == _G)
-  assert(getfenv(loadstring"") == a)
-  return getfenv()
-end
-
-f = coroutine.wrap(foo)
-local a = {}
-assert(f(a) == _G)
-local a,b = pcall(f)
-assert(a and b == _G)
-
-
 -- tests for multiple yield/resume arguments
 
 local function eqtab (t1, t2)
@@ -406,18 +388,4 @@ _X = coroutine.wrap(function ()
 
 _X()
 
-
--- coroutine environments
-co = coroutine.create(function ()
-       coroutine.yield(getfenv(0))
-       return loadstring("return a")()
-     end)
-
-a = {a = 15}
-debug.setfenv(co, a)
-assert(debug.getfenv(co) == a)
-assert(select(2, coroutine.resume(co)) == a)
-assert(select(2, coroutine.resume(co)) == a.a)
-
-
 print'OK'

src/test/resources/assert/lua5.1/locals.lua

@@ -1,20 +1,5 @@
 print('testing local variables plus some extra stuff')
 
-do
-  local i = 10
-  do local i = 100; assert(i==100) end
-  do local i = 1000; assert(i==1000) end
-  assert(i == 10)
-  if i ~= 10 then
-    local i = 20
-  else
-    local i = 30
-    assert(i == 30)
-  end
-end
-
-
-
 f = nil
 
 local f
@@ -50,39 +35,6 @@ assert(x == 1)
 f(2)
 assert(type(f) == 'function')
 
-
--- testing globals ;-)
-do
-  local f = {}
-  local _G = _G
-  for i=1,10 do f[i] = function (x) A=A+1; return A, _G.getfenv(x) end end
-  A=10; assert(f[1]() == 11)
-  for i=1,10 do assert(setfenv(f[i], {A=i}) == f[i]) end
-  assert(f[3]() == 4 and A == 11)
-  local a,b = f[8](1)
-  assert(b.A == 9)
-  a,b = f[8](0)
-  assert(b.A == 11)   -- `real' global
-  local g
-  local function f () assert(setfenv(2, {a='10'}) == g) end
-  g = function () f(); _G.assert(_G.getfenv(1).a == '10') end
-  g(); assert(getfenv(g).a == '10')
-end
-
--- test for global table of loaded chunks
-local function foo (s)
-  return loadstring(s)
-end
-
-assert(getfenv(foo("")) == _G)
-local a = {loadstring = loadstring} 
-setfenv(foo, a)
-assert(getfenv(foo("")) == _G)
-setfenv(0, a)  -- change global environment
-assert(getfenv(foo("")) == a)
-setfenv(0, _G)
-
-
 -- testing limits for special instructions
 
 local a
@@ -109,7 +61,7 @@ print'+'
 if rawget(_G, "querytab") then
   -- testing clearing of dead elements from tables
   collectgarbage("stop")   -- stop GC
-  local a = {[{}] = 4, [3] = 0, alo = 1, 
+  local a = {[{}] = 4, [3] = 0, alo = 1,
              a1234567890123456789012345678901234567890 = 10}
 
   local t = querytab(a)

src/test/resources/assert/lua5.3/db.lua

@@ -818,36 +818,4 @@ local f = assert(load(string.dump(load(prog), true)))
 
 -- assert(f() == 13)
 
-do   -- tests for 'source' in binary dumps
-  local prog = [[
-    return function (x)
-      return function (y)
-        return x + y
-      end
-    end
-  ]]
-  local name = string.rep("x", 1000)
-  local p = assert(load(prog, name))
-  -- load 'p' as a binary chunk with debug information
-  local c = string.dump(p)
-  assert(#c > 1000 and #c < 2000)   -- no repetition of 'source' in dump
-  local f = assert(load(c))
-  local g = f()
-  local h = g(3)
-  assert(h(5) == 8)
-  assert(debug.getinfo(f).source == name and   -- all functions have 'source'
-         debug.getinfo(g).source == name and
-         debug.getinfo(h).source == name)
-  -- again, without debug info
-  local c = string.dump(p, true)
-  assert(#c < 500)   -- no 'source' in dump
-  local f = assert(load(c))
-  local g = f()
-  local h = g(30)
-  assert(h(50) == 80)
-  assert(debug.getinfo(f).source == '=?' and   -- no function has 'source'
-         debug.getinfo(g).source == '=?' and
-         debug.getinfo(h).source == '=?')
-end
-
 print"OK"