From 99c80f56c15a966c4f4f0f31e39fcc35fd454593 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Per=20=C3=96stlund?= <per.ostlund@liu.se>
Date: Mon, 17 Jun 2024 12:41:43 +0200
Subject: [PATCH] Add error for assignment of iterator (#12591)

- Add error message for assigning for an iterator inside a for-loop.
- Improve the error message for using reinit on an iterator.

Fixes #12585
---
 OMCompiler/Compiler/NFFrontEnd/NFInst.mo      |  9 +++++++
 OMCompiler/Compiler/NFFrontEnd/NFTyping.mo    | 15 ++++++++++-
 OMCompiler/Compiler/Util/Error.mo             |  2 ++
 .../modelica/scodeinst/ForStatementAssign1.mo | 23 +++++++++++++++++
 .../flattening/modelica/scodeinst/Makefile    |  2 ++
 .../modelica/scodeinst/ReinitInvalid8.mo      | 25 +++++++++++++++++++
 6 files changed, 75 insertions(+), 1 deletion(-)
 create mode 100644 testsuite/flattening/modelica/scodeinst/ForStatementAssign1.mo
 create mode 100644 testsuite/flattening/modelica/scodeinst/ReinitInvalid8.mo

diff --git a/OMCompiler/Compiler/NFFrontEnd/NFInst.mo b/OMCompiler/Compiler/NFFrontEnd/NFInst.mo
index 1735efc9de..54b4c753e9 100644
--- a/OMCompiler/Compiler/NFFrontEnd/NFInst.mo
+++ b/OMCompiler/Compiler/NFFrontEnd/NFInst.mo
@@ -3541,6 +3541,15 @@ protected
   Restriction res;
 algorithm
   () := match lhs
+    case Expression.CREF()
+      guard ComponentRef.isIterator(lhs.cref)
+      algorithm
+        // Give an error if assigning to an iterator.
+        Error.addSourceMessage(Error.ASSIGN_ITERATOR_ERROR,
+          {ComponentRef.toString(lhs.cref)}, info);
+      then
+        fail();
+
     case Expression.CREF()
       guard ComponentRef.isCref(lhs.cref)
       algorithm
diff --git a/OMCompiler/Compiler/NFFrontEnd/NFTyping.mo b/OMCompiler/Compiler/NFFrontEnd/NFTyping.mo
index de51361f3e..dc095328dd 100644
--- a/OMCompiler/Compiler/NFFrontEnd/NFTyping.mo
+++ b/OMCompiler/Compiler/NFFrontEnd/NFTyping.mo
@@ -3411,6 +3411,10 @@ function checkAssignment
   input InstContext.Type context;
   input SourceInfo info;
 algorithm
+  if InstContext.inInstanceAPI(context) then
+    return;
+  end if;
+
   () := match lhsExp
     local
       Integer i;
@@ -3709,7 +3713,16 @@ algorithm
 
   // The first argument must be a cref.
   cref := match crefExp
-    case Expression.CREF() then crefExp.cref;
+    case Expression.CREF()
+      algorithm
+        if ComponentRef.isIterator(crefExp.cref) then
+          Error.addSourceMessage(Error.ASSIGN_ITERATOR_ERROR,
+            {ComponentRef.toString(crefExp.cref)}, info);
+          fail();
+        end if;
+      then
+        crefExp.cref;
+
     else
       algorithm
         Error.addSourceMessage(Error.REINIT_MUST_BE_VAR_OR_ARRAY, {}, info);
diff --git a/OMCompiler/Compiler/Util/Error.mo b/OMCompiler/Compiler/Util/Error.mo
index f48d8d4afd..3a4c6c0c03 100644
--- a/OMCompiler/Compiler/Util/Error.mo
+++ b/OMCompiler/Compiler/Util/Error.mo
@@ -901,6 +901,8 @@ public constant ErrorTypes.Message NON_FIXED_CONSTANT = ErrorTypes.MESSAGE(413,
   Gettext.gettext("Constant '%s' must be fixed but has 'fixed = false'"));
 public constant ErrorTypes.Message CONFLICTING_INHERITED_ANNOTATIONS = ErrorTypes.MESSAGE(414, ErrorTypes.SCRIPTING(), ErrorTypes.WARNING(),
   Gettext.gettext("Conflicting '%s' annotations inherited by class '%s':\n  %s from 'extends %s'\n  %s from 'extends %s'"));
+public constant ErrorTypes.Message ASSIGN_ITERATOR_ERROR = ErrorTypes.MESSAGE(415, ErrorTypes.TRANSLATION(), ErrorTypes.ERROR(),
+  Gettext.gettext("Assignment to iterator '%s'."));
 
 public constant ErrorTypes.Message INITIALIZATION_NOT_FULLY_SPECIFIED = ErrorTypes.MESSAGE(496, ErrorTypes.TRANSLATION(), ErrorTypes.WARNING(),
   Gettext.gettext("The initial conditions are not fully specified. %s."));
diff --git a/testsuite/flattening/modelica/scodeinst/ForStatementAssign1.mo b/testsuite/flattening/modelica/scodeinst/ForStatementAssign1.mo
new file mode 100644
index 0000000000..ca4a6f72e6
--- /dev/null
+++ b/testsuite/flattening/modelica/scodeinst/ForStatementAssign1.mo
@@ -0,0 +1,23 @@
+// name: ForStatementAssign1
+// keywords:
+// status: incorrect
+// cflags: -d=newInst
+//
+//
+
+model ForStatementAssign1
+algorithm
+  for i in 1:2 loop
+    i := 1;
+  end for;
+end ForStatementAssign1;
+
+// Result:
+// Error processing file: ForStatementAssign1.mo
+// [flattening/modelica/scodeinst/ForStatementAssign1.mo:11:5-11:11:writable] Error: Assignment to iterator 'i'.
+//
+// # Error encountered! Exiting...
+// # Please check the error message and the flags.
+//
+// Execution failed!
+// endResult
diff --git a/testsuite/flattening/modelica/scodeinst/Makefile b/testsuite/flattening/modelica/scodeinst/Makefile
index 1cb07a5342..f8710a4f6c 100644
--- a/testsuite/flattening/modelica/scodeinst/Makefile
+++ b/testsuite/flattening/modelica/scodeinst/Makefile
@@ -542,6 +542,7 @@ ForStatement1.mo \
 ForStatement2.mo \
 ForStatement3.mo \
 ForStatementArray.mo \
+ForStatementAssign1.mo \
 ForStatementNonVector.mo \
 ForStatementPrefix.mo \
 func1.mo \
@@ -1078,6 +1079,7 @@ ReinitInvalid4.mo \
 ReinitInvalid5.mo \
 ReinitInvalid6.mo \
 ReinitInvalid7.mo \
+ReinitInvalid8.mo \
 Return1.mo \
 Return2.mo \
 Size1.mo \
diff --git a/testsuite/flattening/modelica/scodeinst/ReinitInvalid8.mo b/testsuite/flattening/modelica/scodeinst/ReinitInvalid8.mo
new file mode 100644
index 0000000000..50f03c9b88
--- /dev/null
+++ b/testsuite/flattening/modelica/scodeinst/ReinitInvalid8.mo
@@ -0,0 +1,25 @@
+// name: ReinitInvalid8
+// keywords:
+// status: incorrect
+// cflags: -d=newInst
+//
+
+model ReinitInvalid8
+  Real x;
+equation
+  for i in 1.0:2.0 loop
+    when time > 0 then
+      reinit(i, 1.0);
+    end when;
+  end for;
+end ReinitInvalid8;
+
+// Result:
+// Error processing file: ReinitInvalid8.mo
+// [flattening/modelica/scodeinst/ReinitInvalid8.mo:12:7-12:21:writable] Error: Assignment to iterator 'i'.
+//
+// # Error encountered! Exiting...
+// # Please check the error message and the flags.
+//
+// Execution failed!
+// endResult