Merge pull request #98 from czgdp1807/enum_03

Ported ``integration_tests/enum_04.py`` from LPython and improve LC to compile it

integration_tests/CMakeLists.txt

@@ -225,3 +225,4 @@ RUN(NAME nbody_02.cpp LABELS gcc llvm NOFAST)
 
 RUN(NAME enum_01.cpp LABELS gcc llvm NOFAST)
 RUN(NAME enum_02.cpp LABELS gcc llvm NOFAST)
+RUN(NAME enum_03.cpp LABELS gcc llvm NOFAST)

integration_tests/enum_03.cpp

@@ -0,0 +1,87 @@
+#include <iostream>
+
+enum Color {
+    RED,
+    GREEN,
+    BLUE = 7,
+    YELLOW,
+    WHITE,
+    PINK = 15,
+    GREY
+};
+
+enum Integers {
+    a = -5,
+    b,
+    c,
+    d = 0,
+    e,
+    f = 7,
+    g
+};
+
+void assert(bool condition) {
+    if( !condition ) {
+        exit(2);
+    }
+}
+
+void test_color_enum() {
+    std::cout << RED << std::endl;
+    std::cout << GREEN << std::endl;
+    std::cout << BLUE << std::endl;
+    std::cout << YELLOW << std::endl;
+    std::cout << WHITE << std::endl;
+    std::cout << PINK << std::endl;
+    std::cout << GREY << std::endl;
+
+    assert( RED == 0 );
+    assert( GREEN == 1 );
+    assert( BLUE == 7 );
+    assert( YELLOW == 8 );
+    assert( WHITE == 9 );
+    assert( PINK == 15 );
+    assert( GREY == 16 );
+}
+
+void test_selected_color(enum Color selected_color) {
+    enum Color color;
+    color = selected_color;
+    assert( color == YELLOW);
+    std::cout << color << std::endl;
+}
+
+void test_integer(enum Integers integer, int value) {
+    assert(integer == value);
+}
+
+void test_integers() {
+    std::cout << a << std::endl;
+    test_integer(a, -5);
+
+    std::cout << b << std::endl;
+    test_integer(b, -4);
+
+    std::cout << c << std::endl;
+    test_integer(c, -3);
+
+    std::cout << d << std::endl;
+    test_integer(d, 0);
+
+    std::cout << e << std::endl;
+    test_integer(e, 1);
+
+    std::cout << f << std::endl;
+    test_integer(f, 7);
+
+    std::cout << g << std::endl;
+    test_integer(g, 8);
+}
+
+int main() {
+
+test_color_enum();
+test_selected_color(YELLOW);
+test_integers();
+
+}

src/lc/clang_ast_to_asr.cpp

@@ -555,13 +555,22 @@ class ClangASTtoASRVisitor: public clang::RecursiveASTVisitor<ClangASTtoASRVisit
         SymbolTable* parent_scope = current_scope;
         current_scope = al.make_new<SymbolTable>(parent_scope);
         Vec<char*> field_names; field_names.reserve(al, 1);
+        int64_t last_enum_value = 0;
         for( auto enum_const_itr = x->enumerator_begin();
              enum_const_itr != x->enumerator_end(); enum_const_itr++ ) {
             clang::EnumConstantDecl* enum_const = *enum_const_itr;
             std::string enum_const_name = enum_const->getNameAsString();
             field_names.push_back(al, s2c(al, enum_const_name));
-            TraverseStmt(enum_const->getInitExpr());
-            ASR::expr_t* init_expr = ASRUtils::EXPR(tmp.get());
+            ASR::expr_t* init_expr = nullptr;
+            if( enum_const->getInitExpr() ) {
+                TraverseStmt(enum_const->getInitExpr());
+                init_expr = ASRUtils::EXPR(tmp.get());
+                last_enum_value = enum_const->getInitVal().getSExtValue() + 1;
+            } else {
+                init_expr = ASRUtils::EXPR(ASR::make_IntegerConstant_t(al, Lloc(x),
+                    last_enum_value, ASRUtils::TYPE(ASR::make_Integer_t(al, Lloc(x), 4))));
+                last_enum_value += 1;
+            }
             ASR::symbol_t* v = ASR::down_cast<ASR::symbol_t>(ASR::make_Variable_t(al, Lloc(x),
                 current_scope, s2c(al, enum_const_name), nullptr, 0, ASR::intentType::Local,
                 init_expr, init_expr, ASR::storage_typeType::Default, ASRUtils::expr_type(init_expr),