Fix some isues in SNBT parsing

- Accept the full range of unquoted strings
 - Fix error when failing to parse an unquoted string

See #2277. This is not sufficient to close the issue (wow, there's so
much more wrong with the code), but at least stops unserialiseJSON
crashing.

projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/methods/AbstractInventoryMethods.java

@@ -81,11 +81,10 @@ public abstract class AbstractInventoryMethods<T> implements GenericPeripheral {
      * recommended to print it out using [`textutils.serialize`] or in the Lua
      * REPL, to explore what is available.
      * <p>
-     * > [Deprecated fields][!INFO]
-     * > Older versions of CC: Tweaked exposed an {@code itemGroups} field, listing the
-     * > creative tabs an item was available under. This information is no longer available on
-     * > more recent versions of the game, and so this field will always be empty. Do not use this
-     * > field in new code!
+     * > [Missing fields][!INFO]
+     * > CC: Tweaked exposes an {@code itemGroups} field, listing the creative tabs an
+     * > item is available under. This information is not available on Minecraft 1.19.3
+     * > to 1.20.3, and so this field will be empty on those versions.
      *
      * @param inventory The current inventory.
      * @param slot      The slot to get information about.

projects/common/src/main/java/dan200/computercraft/shared/util/InventoryUtil.java

@@ -54,7 +54,7 @@ public final class InventoryUtil {
      */
     public static int getInventorySlotFromCompartment(Player player, int slot, ItemStack stack) {
         if (stack.isEmpty()) throw new IllegalArgumentException("Cannot search for empty stack");
-        if (player.getInventory().getItem(slot) == stack) return slot;
+        if (slot >= 0 && slot < Inventory.INVENTORY_SIZE && player.getInventory().getItem(slot) == stack) return slot;
         if (player.getInventory().getItem(Inventory.SLOT_OFFHAND) == stack) return Inventory.SLOT_OFFHAND;
         return -1;
     }

projects/core-api/src/main/java/dan200/computercraft/api/lua/ObjectLuaTable.java

@@ -61,4 +61,14 @@ public class ObjectLuaTable implements LuaTable<Object, Object> {
     public Set<Entry<Object, Object>> entrySet() {
         return map.entrySet();
     }
+
+    @Override
+    public boolean equals(Object o) {
+        return this == o || o instanceof Map<?, ?> otherMap && map.equals(otherMap);
+    }
+
+    @Override
+    public int hashCode() {
+        return map.hashCode();
+    }
 }

projects/core/src/main/java/dan200/computercraft/core/asm/Generator.java

@@ -73,6 +73,22 @@ final class Generator<T> {
             addArgType(argMethodMap, Map.class, "Table");
             addArgType(argMethodMap, String.class, "String");
             addArgType(argMethodMap, ByteBuffer.class, "Bytes");
+            argMethodMap.put(LuaTable.class, new ArgMethods(
+                // i -> new ObjectLuaTable(getTable(i))
+                MethodHandles.filterReturnValue(
+                    LOOKUP.findVirtual(IArguments.class, "getTable", MethodType.methodType(Map.class, int.class)),
+                    LOOKUP.findConstructor(ObjectLuaTable.class, MethodType.methodType(void.class, Map.class))
+                        .asType(MethodType.methodType(LuaTable.class, Map.class))
+                ),
+                // i -> optTable(i).map(ObjectLuaTable::new)
+                MethodHandles.filterReturnValue(
+                    LOOKUP.findVirtual(IArguments.class, "optTable", MethodType.methodType(Optional.class, int.class)),
+                    MethodHandles.insertArguments(
+                        LOOKUP.findVirtual(Optional.class, "map", MethodType.methodType(Optional.class, Function.class)),
+                        1, (Function<Map<?, ?>, LuaTable<?, ?>>) ObjectLuaTable::new
+                    )
+                )
+            ));
             argMethods = Map.copyOf(argMethodMap);
 
             ARG_TABLE_UNSAFE = ArgMethods.of(LuaTable.class, "TableUnsafe");
@@ -335,10 +351,9 @@ final class Generator<T> {
     }
 
     private static @Nullable ArgMethods getArgMethods(Class<?> type, boolean unsafe) {
-        var getter = argMethods.get(type);
-        if (getter != null) return getter;
         if (type == LuaTable.class && unsafe) return ARG_TABLE_UNSAFE;
-        return null;
+
+        return argMethods.get(type);
     }
 
     /**

projects/core/src/main/java/dan200/computercraft/core/lua/VarargArguments.java

@@ -20,13 +20,8 @@ import static org.squiddev.cobalt.Constants.NAME;
 final class VarargArguments implements IArguments {
     private static final Logger LOG = LoggerFactory.getLogger(VarargArguments.class);
 
-    private static final VarargArguments EMPTY = new VarargArguments(Constants.NONE);
     private static boolean reportedIllegalGet;
 
-    static {
-        EMPTY.escapes = EMPTY.closed = true;
-    }
-
     private final Varargs varargs;
 
     private volatile boolean closed;
@@ -51,7 +46,7 @@ final class VarargArguments implements IArguments {
     }
 
     static VarargArguments of(Varargs values) {
-        return values == Constants.NONE ? EMPTY : new VarargArguments(values);
+        return new VarargArguments(values);
     }
 
     boolean isClosed() {
@@ -138,9 +133,7 @@ final class VarargArguments implements IArguments {
         if (count < 0) throw new IllegalStateException("count cannot be negative");
         if (count == 0) return this;
 
-        var newArgs = varargs.subargs(count + 1);
-        if (newArgs == Constants.NONE) return EMPTY;
-        return new VarargArguments(newArgs, this, count);
+        return new VarargArguments(varargs.subargs(count + 1), this, count);
     }
 
     @Override

projects/core/src/main/resources/data/computercraft/lua/rom/apis/textutils.lua

@@ -616,7 +616,8 @@ do
     end
 
     local function parse_ident(str, pos)
-        local _, last, val = find(str, '^([%a][%w_]*)', pos)
+        local _, last, val = find(str, '^([%w_+.-]+)', pos)
+        if not last then error_at(pos, "Expected object key") end
         return val, last + 1
     end
 
@@ -864,7 +865,7 @@ values do not serialise cleanly into JSON.
    A consequence of this is that an empty table will always be serialised to an object,
    not an array. [`textutils.empty_json_array`] may be used to express an empty array.
 
- - Lua strings are an a sequence of raw bytes, and do not have any specific encoding.
+ - Lua strings are a sequence of raw bytes, and do not have any specific encoding.
    However, JSON strings must be valid unicode. By default, non-ASCII characters in a
    string are serialised to their unicode code point (for instance, `"\xfe"` is
    converted to `"\u00fe"`). The `unicode_strings` option may be set to treat all input

projects/core/src/main/resources/data/computercraft/lua/rom/modules/main/cc/audio/dfpwm.lua

@@ -8,8 +8,8 @@ Convert between streams of DFPWM audio data and a list of amplitudes.
 DFPWM (Dynamic Filter Pulse Width Modulation) is an audio codec designed by GreaseMonkey. It's a relatively compact
 format compared to raw PCM data, only using 1 bit per sample, but is simple enough to encode and decode in real time.
 
-Typically DFPWM audio is read from [the filesystem][`fs.ReadHandle`] or a [a web request][`http.Response`] as a string,
-and converted a format suitable for [`speaker.playAudio`].
+Typically DFPWM audio is read from [the filesystem][`fs.ReadHandle`] or [a web request][`http.Response`] as a string,
+and converted to a format suitable for [`speaker.playAudio`].
 
 ## Encoding and decoding files
 This module exposes two key functions, [`make_decoder`] and [`make_encoder`], which construct a new decoder or encoder.

projects/core/src/test/java/dan200/computercraft/core/asm/GeneratorTest.java

@@ -10,6 +10,7 @@ import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.core.methods.LuaMethod;
 import dan200.computercraft.core.methods.NamedMethod;
 import org.hamcrest.Matcher;
+import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.Test;
 import org.objectweb.asm.ClassReader;
 import org.objectweb.asm.ClassVisitor;
@@ -123,6 +124,17 @@ public class GeneratorTest {
         assertThrows(LuaException.class, () -> apply(methods, new EnumMethods(), "getEnum", "not as side"));
     }
 
+    @Test
+    public void testLuaTable() throws LuaException {
+        var methods = GENERATOR.getMethods(TableMethods.class);
+        assertThat(methods, containsInAnyOrder(named("getTable"), named("optTable")));
+
+        assertThat(apply(methods, new TableMethods(), "getTable", Map.of("x", "y")), one(is(Map.of("x", "y"))));
+        assertThat(apply(methods, new TableMethods(), "optTable", Map.of("x", "y")), one(is(Map.of("x", "y"))));
+        assertThat(apply(methods, new TableMethods(), "optTable"), one(nullValue()));
+        assertThrows(LuaException.class, () -> apply(methods, new TableMethods(), "getTable", "not a table"));
+    }
+
     @Test
     public void testMainThread() throws LuaException {
         var methods = GENERATOR.getMethods(MainThread.class);
@@ -277,6 +289,18 @@ public class GeneratorTest {
         }
     }
 
+    public static class TableMethods {
+        @LuaFunction
+        public final LuaTable<?, ?> getTable(LuaTable<?, ?> table) {
+            return table;
+        }
+
+        @LuaFunction
+        public final @Nullable LuaTable<?, ?> optTable(Optional<LuaTable<?, ?>> table) {
+            return table.orElse(null);
+        }
+    }
+
     public static class MainThread {
         @LuaFunction(mainThread = true)
         public final void go() {
@@ -288,10 +312,6 @@ public class GeneratorTest {
         public final void withUnsafe(LuaTable<?, ?> table) {
         }
 
-        @LuaFunction
-        public final void withoutUnsafe(LuaTable<?, ?> table) {
-        }
-
         @LuaFunction(unsafe = true, mainThread = true)
         public final void invalid(LuaTable<?, ?> table) {
         }

projects/core/src/test/resources/test-rom/spec/apis/textutils_spec.lua

@@ -246,11 +246,25 @@ describe("The textutils library", function()
         describe("parses using NBT-style syntax", function()
             local function exp(x)
                 local res, err = textutils.unserializeJSON(x, { nbt_style = true })
-                if not res then error(err, 2) end
+                if not res then fail(err) end
                 return expect(res)
             end
+
+            local function exp_err(x)
+                local res, err = textutils.unserializeJSON(x, { nbt_style = true })
+                if res ~= nil then
+                    fail(("Expected %q not to parse, but returned %s"):format(x, textutils.serialise(res)))
+                end
+                return expect(err)
+            end
+
             it("basic objects", function()
-                exp([[{ a: 1, b:2 }]]):same { a = 1, b = 2 }
+                exp("{ a: 1, b:2 }"):same { a = 1, b = 2 }
+                exp("{0+_-.aA: 1}"):same { ["0+_-.aA"] = 1 }
+                exp("{}"):same {}
+
+                exp_err("{: 123}"):eq("Malformed JSON at position 2: Expected object key")
+                exp_err("{#: 123}"):eq("Malformed JSON at position 2: Expected object key")
             end)
 
             it("suffixed numbers", function()
@@ -258,9 +272,21 @@ describe("The textutils library", function()
                 exp("1.1d"):eq(1.1)
             end)
 
-            it("strings", function()
-                exp("'123'"):eq("123")
-                exp("\"123\""):eq("123")
+            describe("strings", function()
+                it("empty quoted strings", function()
+                    exp("''"):eq("")
+                    exp("\"\""):eq("")
+                end)
+
+                pending("unquoted strings", function()
+                    exp("hello"):eq("hello")
+                    exp("0+_-.aA"):eq("0+_-.aA")
+                end)
+
+                it("quoted strings", function()
+                    exp("'123'"):eq("123")
+                    exp("\"123\""):eq("123")
+                end)
             end)
 
             it("typed arrays", function()