Add str.swapcase() to compile time

AbdelrahmanKhaledd · AbdelrahmanKhaledd · commit ac1e51feef0a · 2022-09-02T20:05:33.000+02:00
diff --git a/src/lpython/semantics/python_ast_to_asr.cpp b/src/lpython/semantics/python_ast_to_asr.cpp
@@ -4421,6 +4421,25 @@ class BodyVisitor : public CommonVisitor<BodyVisitor> {
                                     1, 1, nullptr, nullptr , 0));
                     tmp = ASR::make_StringConstant_t(al, x.base.base.loc, s2c(al, res), str_type);
                     return;
+                } else if (std::string(at->m_attr) == std::string("swapcase")) {
+                    if(args.size() != 0) {
+                        throw SemanticError("str.swapcase() takes no arguments",
+                            x.base.base.loc);
+                    }
+                    AST::ConstantStr_t *n = AST::down_cast<AST::ConstantStr_t>(at->m_value);
+                    std::string res = n->m_value;
+                    for (size_t i = 0; i < res.size(); i++)  {
+                        char &cur = res[i];
+                        if(cur >= 'a' && cur <= 'z') {
+                            cur = cur -'a' + 'A';
+                        } else if(cur >= 'A' && cur <= 'Z') {
+                            cur = cur - 'A' + 'a';
+                        }
+                    }
+                    ASR::ttype_t *str_type = ASRUtils::TYPE(ASR::make_Character_t(al, x.base.base.loc,
+                                    1, 1, nullptr, nullptr , 0));
+                    tmp = ASR::make_StringConstant_t(al, x.base.base.loc, s2c(al, res), str_type);
+                    return;
                 } else if (std::string(at->m_attr) == std::string("startswith")) {
                     if (args.size() != 1) {
                         throw SemanticError("str.startswith() takes one arguments",
diff --git a/src/lpython/semantics/python_comptime_eval.h b/src/lpython/semantics/python_comptime_eval.h
@@ -68,6 +68,7 @@ struct PythonIntrinsicProcedures {
             {"_lpython_str_rstrip", {m_builtin, &eval__lpython_str_rstrip}},
             {"_lpython_str_lstrip", {m_builtin, &eval__lpython_str_lstrip}},
             {"_lpython_str_strip", {m_builtin, &eval__lpython_str_strip}},
+            {"_lpython_str_swapcase", {m_builtin, &eval__lpython_str_swapcase}},
             {"_lpython_str_startswith", {m_builtin, &eval__lpython_str_startswith}}
         };
     }
@@ -742,7 +743,16 @@ struct PythonIntrinsicProcedures {
         ASR::ttype_t *res_type = ASRUtils::TYPE(ASR::make_StringConstant_t(al, loc, s2c(al, ""), type));
         return ASR::down_cast<ASR::expr_t>(ASR::make_StringConstant_t(al, loc, s2c(al, res),  res_type));
     }
-    
+
+    static ASR::expr_t *eval__lpython_str_swapcase(Allocator &al, const Location &loc, Vec<ASR::expr_t *> &args) {
+        LFORTRAN_ASSERT(ASRUtils::all_args_evaluated(args));
+        std::string res = "";
+        ASR::ttype_t *type = ASRUtils::TYPE(ASR::make_Character_t(al, loc,
+                                    1, 1, nullptr, nullptr, 0));
+        ASR::ttype_t *res_type = ASRUtils::TYPE(ASR::make_StringConstant_t(al, loc, s2c(al, ""), type));
+        return ASR::down_cast<ASR::expr_t>(ASR::make_StringConstant_t(al, loc, s2c(al, res),  res_type));
+    }
+
     static ASR::expr_t *eval_lpython_str_find(Allocator &al, const Location &loc, Vec<ASR::expr_t *> &/*args*/) {
         // compile time action implemented on ast->asr
         ASR::ttype_t *int_type = ASRUtils::TYPE(ASR::make_Integer_t(al, loc, 4, nullptr, 0));
