code suggestions

src/main/java/carpet/commands/ScriptCommand.java

@@ -14,6 +14,8 @@ import com.mojang.brigadier.CommandDispatcher;
 import com.mojang.brigadier.arguments.StringArgumentType;
 import com.mojang.brigadier.builder.LiteralArgumentBuilder;
 import com.mojang.brigadier.context.CommandContext;
+import com.mojang.brigadier.suggestion.Suggestions;
+import com.mojang.brigadier.suggestion.SuggestionsBuilder;
 import net.minecraft.block.Block;
 import net.minecraft.block.pattern.CachedBlockPosition;
 import net.minecraft.command.arguments.BlockPosArgumentType;
@@ -31,6 +33,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Locale;
+import java.util.concurrent.CompletableFuture;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 
@@ -40,6 +43,31 @@ import static net.minecraft.server.command.CommandSource.suggestMatching;
 
 public class ScriptCommand
 {
+
+    private static CompletableFuture<Suggestions> suggestCode(SuggestionsBuilder suggestionsBuilder) {
+        String previous = suggestionsBuilder.getRemaining().toLowerCase(Locale.ROOT);
+        int strlen = previous.length();
+        StringBuilder lastToken = new StringBuilder();
+        for (int idx = strlen-1; idx >=0; idx--)
+        {
+            char ch = previous.charAt(idx);
+            if (Character.isLetterOrDigit(ch) || ch == '_')
+            {
+                lastToken.append(ch);
+            }
+            else
+            {
+                break;
+            }
+        }
+        if (lastToken.length() == 0)
+            return suggestionsBuilder.buildFuture();
+        String prefix = lastToken.reverse().toString();
+        String previousString =  previous.substring(0,previous.length()-prefix.length()) ;
+        ExpressionInspector.suggestFunctions(previousString, prefix).forEach(text -> suggestionsBuilder.suggest(previousString+text));
+        return suggestionsBuilder.buildFuture();
+    }
+
     public static void register(CommandDispatcher<ServerCommandSource> dispatcher)
     {
         LiteralArgumentBuilder<ServerCommandSource> b = literal("globals").
@@ -50,7 +78,7 @@ public class ScriptCommand
                 executes( (cc) -> { CarpetServer.scriptServer.stopAll = false; return 1;});
         LiteralArgumentBuilder<ServerCommandSource> l = literal("run").
                 requires((player) -> player.hasPermissionLevel(2)).
-                then(argument("expr", StringArgumentType.greedyString()).
+                then(argument("expr", StringArgumentType.greedyString()).suggests((cc, bb) -> suggestCode(bb)).
                         executes((cc) -> compute(
                                 cc,
                                 StringArgumentType.getString(cc, "expr"))));
@@ -113,6 +141,7 @@ public class ScriptCommand
                         then(argument("from", BlockPosArgumentType.create()).
                                 then(argument("to", BlockPosArgumentType.create()).
                                         then(argument("expr", StringArgumentType.greedyString()).
+                                                suggests((cc, bb) -> suggestCode(bb)).
                                                 executes( (cc) -> scriptScan(
                                                         cc,
                                                         BlockPosArgumentType.getBlockPos(cc, "origin"),

src/main/java/carpet/script/CarpetExpression.java

@@ -101,6 +101,7 @@ public class CarpetExpression
     private ServerCommandSource source;
     private BlockPos origin;
     private Expression expr;
+    Expression getExpr() {return expr;}
     private static long tickStart = 0L;
 
     private static boolean stopAll = false;
@@ -766,6 +767,8 @@ public class CarpetExpression
 
         this.expr.addLazyFunction("harvest", -1, (c, t, lv) ->
         {
+            if (lv.size()<2)
+                throw new InternalExpressionException("harvest takes at least 2 parameters: entity and block, or position, to harvest");
             CarpetContext cc = (CarpetContext)c;
             World world = cc.s.getWorld();
             Value entityValue = lv.get(0).evalValue(cc);
@@ -791,14 +794,12 @@ public class CarpetExpression
 
         this.expr.addLazyFunction("place_item", -1, (c, t, lv) ->
         {
+            if (lv.size()<2)
+                throw new InternalExpressionException("place_item takes at least 2 parameters: item and block, or position, to place onto");
             CarpetContext cc = (CarpetContext) c;
             String itemString = lv.get(0).evalValue(c).getString();
             BlockValue.VectorLocator locator = BlockValue.locateVec(cc, lv, 1);
             ItemStackArgument stackArg = NBTSerializableValue.parseItem(itemString);
-            if (stackArg == null)
-            {
-                throw new InternalExpressionException("unknown item: "+itemString);
-            }
             BlockPos where = new BlockPos(locator.vec);
             String facing = "up";
             if (lv.size() > locator.offset)
@@ -876,6 +877,8 @@ public class CarpetExpression
         this.expr.addLazyFunction("inventory_get", -1, (c, t, lv) -> {
             CarpetContext cc = (CarpetContext) c;
             NBTSerializableValue.InventoryLocator inventoryLocator = NBTSerializableValue.locateInventory(cc, lv, 0);
+            if (inventoryLocator == null)
+                return (_c, _t) -> Value.NULL;
             if (lv.size() == inventoryLocator.offset)
             {
                 List<Value> fullInventory = new ArrayList<>();
@@ -897,6 +900,8 @@ public class CarpetExpression
         this.expr.addLazyFunction("inventory_drop", -1, (c, t, lv) -> {
             CarpetContext cc = (CarpetContext) c;
             NBTSerializableValue.InventoryLocator inventoryLocator = NBTSerializableValue.locateInventory(cc, lv, 0);
+            if (inventoryLocator == null)
+                return (_c, _t) -> Value.NULL;
             if (lv.size() == inventoryLocator.offset)
                 throw new InternalExpressionException("slot number is required for inventory_drop");
             int slot = (int)NumericValue.asNumber(lv.get(inventoryLocator.offset).evalValue(c)).getLong();
@@ -947,16 +952,14 @@ public class CarpetExpression
         this.expr.addLazyFunction("inventory_find", -1, (c, t, lv) -> {
             CarpetContext cc = (CarpetContext) c;
             NBTSerializableValue.InventoryLocator inventoryLocator = NBTSerializableValue.locateInventory(cc, lv, 0);
+            if (inventoryLocator == null)
+                return (_c, _t) -> Value.NULL;
             ItemStackArgument itemArg = null;
             if (lv.size() > inventoryLocator.offset)
             {
                 Value secondArg = lv.get(inventoryLocator.offset+0).evalValue(c);
                 if (!(secondArg instanceof NullValue))
-                {
                     itemArg = NBTSerializableValue.parseItem(secondArg.getString());
-                    if (itemArg == null)
-                        throw new InternalExpressionException("Incorrect item format: "+secondArg.getString());
-                }
             }
             int startIndex = 0;
             if (lv.size() > inventoryLocator.offset+1)
@@ -980,7 +983,8 @@ public class CarpetExpression
         this.expr.addLazyFunction("inventory_set", -1, (c, t, lv) -> {
             CarpetContext cc = (CarpetContext) c;
             NBTSerializableValue.InventoryLocator inventoryLocator = NBTSerializableValue.locateInventory(cc, lv, 0);
-
+            if (inventoryLocator == null)
+                return (_c, _t) -> Value.NULL;
             if (lv.size() < inventoryLocator.offset+2)
                 throw new InternalExpressionException("inventory_set requires at least slot number and new stack size, and optional new item");
             int slot = (int) NumericValue.asNumber(lv.get(inventoryLocator.offset+0).evalValue(c)).getLong();
@@ -1019,7 +1023,8 @@ public class CarpetExpression
         this.expr.addLazyFunction("inventory_remove", -1, (c, t, lv) -> {
             CarpetContext cc = (CarpetContext) c;
             NBTSerializableValue.InventoryLocator inventoryLocator = NBTSerializableValue.locateInventory(cc, lv, 0);
-
+            if (inventoryLocator == null)
+                return (_c, _t) -> Value.NULL;
             if (lv.size() <= inventoryLocator.offset)
                 throw new InternalExpressionException("inventory_set requires at least an item to be removed");
             ItemStackArgument searchItem = NBTSerializableValue.parseItem(lv.get(inventoryLocator.offset).evalValue(c).getString());

src/main/java/carpet/script/Expression.java

@@ -32,6 +32,7 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Random;
+import java.util.Set;
 import java.util.Stack;
 import java.util.function.BiFunction;
 import java.util.function.Function;
@@ -350,6 +351,7 @@ public class Expression implements Cloneable
     boolean isAnOperator(String opname) { return operators.containsKey(opname) || operators.containsKey(opname+"u");}
 
     private Map<String, ILazyFunction> functions = new HashMap<>();
+    Set<String> getFunctionNames() {return functions.keySet();}
 
     //static final Map<String, UserDefinedFunction> globalFunctions = new HashMap<>();
 

src/main/java/carpet/script/ExpressionInspector.java

@@ -1,6 +1,13 @@
 package carpet.script;
 
+import carpet.CarpetServer;
+import org.apache.commons.lang3.StringUtils;
+
+import java.util.Collections;
 import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.stream.Collectors;
 
 /**
  * sole purpose of this package is to provide public access to package-private methods of Expression and CarpetExpression
@@ -17,4 +24,29 @@ public class ExpressionInspector
     {
         return e.getName();
     }
+
+    private static TreeSet<String> scarpetFunctions;
+    private static TreeSet<String> APIFunctions;
+    static
+    {
+        Set<String> allFunctions = (new CarpetExpression("null", null, null)).getExpr().getFunctionNames();
+        scarpetFunctions = new TreeSet<>(new Expression("null").getFunctionNames());
+        APIFunctions = new TreeSet<>(allFunctions.stream().filter(s -> !scarpetFunctions.contains(s)).collect(Collectors.toSet()));
+    }
+
+    public static List<String> suggestFunctions(String previous, String prefix)
+    {
+        previous = previous.replace("\\'", "");
+        int quoteCount = StringUtils.countMatches(previous,'\'');
+        if (quoteCount % 2 == 1)
+            return Collections.emptyList();
+        int maxLen = prefix.length()<3 ? (prefix.length()*2+1) : 1234;
+        List<String> scarpetMatches = scarpetFunctions.stream().
+                filter(s -> s.startsWith(prefix) && s.length() <= maxLen).map(s -> s+"(").collect(Collectors.toList());
+        scarpetMatches.addAll(APIFunctions.stream().
+                filter(s -> s.startsWith(prefix) && s.length() <= maxLen).map(s -> s+"(").collect(Collectors.toList()));
+        scarpetMatches.addAll(CarpetServer.scriptServer.globalHost.globalVariables.keySet().stream().
+                filter(s -> s.startsWith(prefix)).collect(Collectors.toList()));
+        return scarpetMatches;
+    }
 }

src/main/java/carpet/script/value/NBTSerializableValue.java

@@ -51,7 +51,7 @@ public class NBTSerializableValue extends Value
                 else if (e instanceof VillagerEntity) inv = ((VillagerEntity) e).getInventory();
 
                 if (inv == null)
-                    throw new InternalExpressionException("Entity " + e + " has no inventory");
+                    return null;
 
                 return new InventoryLocator(e, e.getBlockPos(), inv, offset + 1);
             }
@@ -59,10 +59,10 @@ public class NBTSerializableValue extends Value
             {
                 BlockPos pos = ((BlockValue) v1).getPos();
                 if (pos == null)
-                    throw new InternalExpressionException("Block to acess inventory needs to be positioned in the world");
+                    throw new InternalExpressionException("Block to access inventory needs to be positioned in the world");
                 inv = HopperBlockEntity.getInventoryAt(c.s.getWorld(), pos);
                 if (inv == null)
-                    throw new InternalExpressionException("Block at " + pos + " has no inventory");
+                    return null;
                 return new InventoryLocator(pos, pos, inv, offset + 1);
             }
             else if (v1 instanceof ListValue)
@@ -74,7 +74,7 @@ public class NBTSerializableValue extends Value
                         NumericValue.asNumber(args.get(2)).getDouble());
                 inv = HopperBlockEntity.getInventoryAt(c.s.getWorld(), pos);
                 if (inv == null)
-                    throw new InternalExpressionException("Block at " + pos + " has no inventory");
+                    return null;
                 return new InventoryLocator(pos, pos, inv, offset + 1);
             }
             BlockPos pos = new BlockPos(
@@ -83,7 +83,7 @@ public class NBTSerializableValue extends Value
                     NumericValue.asNumber(params.get(2 + offset).evalValue(c)).getDouble());
             inv = HopperBlockEntity.getInventoryAt(c.s.getWorld(), pos);
             if (inv == null)
-                throw new InternalExpressionException("Block at " + pos + " has no inventory");
+                return null;
             return new InventoryLocator(pos, pos, inv, offset + 3);
         }
         catch (IndexOutOfBoundsException e)
@@ -109,7 +109,7 @@ public class NBTSerializableValue extends Value
         }
         catch (CommandSyntaxException e)
         {
-            return null;
+            throw new InternalExpressionException("Incorrect item: "+itemString);
         }
     }