Check unit empty

src/parser/nmodl.yy

@@ -565,7 +565,6 @@ units           :   {
 
 unit            :   "(" { scanner.scan_unit(); } ")"
                     {
-                        // @todo Empty units should be handled in semantic analysis
                         auto unit = scanner.get_unit();
                         auto text = unit->eval();
                         $$ = new ast::Unit(unit);

src/visitors/semantic_analysis_visitor.cpp

@@ -7,6 +7,7 @@
 #include "ast/string.hpp"
 #include "ast/suffix.hpp"
 #include "ast/table_statement.hpp"
+#include "ast/unit.hpp"
 #include "symtab/symbol_properties.hpp"
 #include "utils/logger.hpp"
 #include "visitors/visitor_utils.hpp"
@@ -163,5 +164,13 @@ void SemanticAnalysisVisitor::visit_mutex_unlock(const ast::MutexUnlock& /* node
     /// -->
 }
 
+void SemanticAnalysisVisitor::visit_unit(const ast::Unit& node) {
+    /// <-- This code is for check 8
+    if (node.get_name()->get_value().empty()) {
+        logger->error("SemanticAnalysisVisitor:: An unit cannot be created without name.");
+        check_fail = true;
+    }
+}
+
 }  // namespace visitor
 }  // namespace nmodl

src/visitors/semantic_analysis_visitor.hpp

@@ -29,8 +29,9 @@
  * 3. A TABLE statement in functions cannot have name list, and should have one in procedures.
  * 4. Check if ion variables from a `USEION` statement are not declared in `CONSTANT` block.
  * 5. Check if an independent variable is not 't'.
- * 6. Check that mutex are not badly use
+ * 6. Check that mutex are not badly use.
  * 7. Check than function table got at least one argument.
+ * 8. Check that unit always have a name.
  */
 #include "ast/ast.hpp"
 #include "visitors/ast_visitor.hpp"
@@ -82,6 +83,9 @@ class SemanticAnalysisVisitor: public ConstAstVisitor {
     /// Look if MUTEXUNLOCK is outside a locked block
     void visit_mutex_unlock(const ast::MutexUnlock& node) override;
 
+    /// Visit an unit and check that name is not empty
+    void visit_unit(const ast::Unit& node) override;
+
   public:
     SemanticAnalysisVisitor(bool accel_backend = false)
         : accel_backend(accel_backend) {}

test/unit/visitor/semantic_analysis.cpp

@@ -165,3 +165,34 @@ SCENARIO("FUNCTION_TABLE block", "[visitor][semantic_analysis]") {
         }
     }
 }
+
+SCENARIO("UNITS block", "[visitor][semantic_analysis]") {
+    GIVEN("A mod file with UNITS empty") {
+        std::string nmodl_text = R"(
+            UNITS {}
+        )";
+        THEN("Semantic analysis should success") {
+            REQUIRE_FALSE(run_semantic_analysis_visitor(nmodl_text));
+        }
+    }
+    GIVEN("A mod file with UNITS with space as name") {
+        std::string nmodl_text = R"(
+            UNITS {
+                ( ) = (millivolt)
+            }
+        )";
+        THEN("Semantic analysis should success") {
+            REQUIRE_FALSE(run_semantic_analysis_visitor(nmodl_text));
+        }
+    }
+    GIVEN("A mod file with UNITS with no name") {
+        std::string nmodl_text = R"(
+            UNITS {
+                () = (millivolt)
+            }
+        )";
+        THEN("Semantic analysis should fail") {
+            REQUIRE(run_semantic_analysis_visitor(nmodl_text));
+        }
+    }
+}