Merge pull request #672 from dictu-lang/feature/enum

Add new Enum.values() method

Author: Jason2605

docs/docs/enum.md

@@ -49,4 +49,18 @@ enum HeterogeneousEnum {
     b = "string",
     c = def () => 10
 }
+```
+
+### Enum.values()
+
+To get all values within an Enum you can use the `.values()` method. This will return a dictionary.
+
+```cs
+enum Test {
+    a = 10, // 10
+    b,      // 1
+    c       // 2
+}
+
+print(Test.values()); // {"c": 2, "a": 10, "b": 1}
 ```

src/vm/compiler.c

@@ -1977,7 +1977,7 @@ static void enumDeclaration(Compiler *compiler) {
 
     do {
         if (check(compiler, TOKEN_RIGHT_BRACE)) {
-            error(compiler->parser, "Trailing comma in enum declaration");
+            break;
         }
 
         consume(compiler, TOKEN_IDENTIFIER, "Expect enum value identifier.");

src/vm/datatypes/enums.c

@@ -0,0 +1,28 @@
+#include "enums.h"
+
+static Value values(DictuVM *vm, int argCount, Value *args) {
+    if (argCount != 0) {
+        runtimeError(vm, "values() takes 0 arguments (%d given)", argCount);
+        return EMPTY_VAL;
+    }
+
+    ObjEnum *objEnum = AS_ENUM(args[0]);
+    ObjDict *dict = newDict(vm);
+    push(vm, OBJ_VAL(dict));
+
+    for (int i = 0; i < objEnum->values.capacityMask + 1; ++i) {
+        if (objEnum->values.entries[i].key == NULL) {
+            continue;
+        }
+
+        dictSet(vm, dict, OBJ_VAL(objEnum->values.entries[i].key), objEnum->values.entries[i].value);
+    }
+
+    pop(vm);
+
+    return OBJ_VAL(dict);
+}
+
+void declareEnumMethods(DictuVM *vm) {
+    defineNative(vm, &vm->enumMethods, "values", values);
+}

src/vm/datatypes/enums.h

@@ -0,0 +1,9 @@
+#ifndef dictu_api_enums_h
+#define dictu_api_enums_h
+
+#include "../common.h"
+#include "../util.h"
+
+void declareEnumMethods(DictuVM *vm);
+
+#endif //dictu_api_enums_h

src/vm/memory.c

@@ -349,6 +349,7 @@ void collectGarbage(DictuVM *vm) {
     grayTable(vm, &vm->classMethods);
     grayTable(vm, &vm->instanceMethods);
     grayTable(vm, &vm->resultMethods);
+    grayTable(vm, &vm->enumMethods);
     grayCompilerRoots(vm);
     grayObject(vm, (Obj *) vm->initString);
     grayObject(vm, (Obj *) vm->annotationString);

src/vm/vm.c

@@ -23,6 +23,7 @@
 #include "datatypes/class.h"
 #include "datatypes/instance.h"
 #include "datatypes/result/result.h"
+#include "datatypes/enums.h"
 #include "natives.h"
 #include "../optionals/optionals.h"
 
@@ -120,6 +121,7 @@ DictuVM *dictuInitVM(bool repl, int argc, char **argv) {
     initTable(&vm->classMethods);
     initTable(&vm->instanceMethods);
     initTable(&vm->resultMethods);
+    initTable(&vm->enumMethods);
 
     vm->frames = ALLOCATE(vm, CallFrame, vm->frameCapacity);
     vm->initString = copyString(vm, "init", 4);
@@ -140,6 +142,7 @@ DictuVM *dictuInitVM(bool repl, int argc, char **argv) {
     declareClassMethods(vm);
     declareInstanceMethods(vm);
     declareResultMethods(vm);
+    declareEnumMethods(vm);
 
     if (vm->repl) {
         vm->replVar = copyString(vm, "_", 1);
@@ -168,6 +171,7 @@ void dictuFreeVM(DictuVM *vm) {
     freeTable(vm, &vm->classMethods);
     freeTable(vm, &vm->instanceMethods);
     freeTable(vm, &vm->resultMethods);
+    freeTable(vm, &vm->enumMethods);
     FREE_ARRAY(vm, CallFrame, vm->frames, vm->frameCapacity);
     vm->initString = NULL;
     vm->replVar = NULL;
@@ -647,14 +651,28 @@ static bool invoke(DictuVM *vm, ObjString *name, int argCount, bool unpack) {
             }
 
             case OBJ_ENUM: {
+                Value value;
+                if (tableGet(&vm->enumMethods, name, &value)) {
+                    if (IS_NATIVE(value)) {
+                        return callNativeMethod(vm, value, argCount);
+                    }
+
+                    push(vm, peek(vm, 0));
+
+                    for (int i = 2; i <= argCount + 1; i++) {
+                        vm->stackTop[-i] = peek(vm, i);
+                    }
+
+                    return call(vm, AS_CLOSURE(value), argCount + 1);
+                }
+
                 ObjEnum *enumObj = AS_ENUM(receiver);
 
-                Value value;
                 if (tableGet(&enumObj->values, name, &value)) {
                     return callValue(vm, value, argCount, false);
                 }
 
-                runtimeError(vm, "'%s' enum has no value '%s'.", enumObj->name->chars, name->chars);
+                runtimeError(vm, "Enum has no method '%s'.", name->chars);
                 return false;
             }
 

src/vm/vm.h

@@ -39,6 +39,7 @@ struct _vm {
     Table classMethods;
     Table instanceMethods;
     Table resultMethods;
+    Table enumMethods;
     ObjString *initString;
     ObjString *annotationString;
     ObjString *replVar;

tests/enum/enum.du

@@ -58,6 +58,36 @@ class TestEnums < UnitTest {
         this.assertEquals(HeterogeneousEnum.c, func);
         this.assertEquals(HeterogeneousEnum.c(), 10);
     }
+
+    testGetValues() {
+        enum MyEnum {
+            a,
+            b,
+            c
+        }
+
+        const values = MyEnum.values();
+
+        this.assertEquals(values["a"], 0);
+        this.assertEquals(values["b"], 1);
+        this.assertEquals(values["c"], 2);
+    }
+
+    testGetValuesHeterogeneousEnum() {
+        const func = def () => 10;
+
+        enum HeterogeneousEnum {
+            a = 0,
+            b = "string",
+            c = func
+        }
+
+        const values = HeterogeneousEnum.values();
+
+        this.assertEquals(values["a"], 0);
+        this.assertEquals(values["b"], "string");
+        this.assertEquals(values["c"], func);
+    }
 }
 
 TestEnums().run();