Print error for data statement after non-data statement

Resolves #10
iafisher · Dec 13, 2018 · 2690bbd · 2690bbd
1 parent 21acf72
commit 2690bbd
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Showing 2 changed files with 19 additions and 0 deletions.
diff --git a/hera/typechecker.py b/hera/typechecker.py
@@ -8,9 +8,19 @@
 from .utils import emit_error, is_symbol, register_to_index
 
 
+DATA_STATEMENTS = set(["CONSTANT", "DLABEL", "INTEGER", "LP_STRING", "DSKIP"])
+
+
 def typecheck(program):
     """Type-check the program and emit errors as appropriate."""
+    end_of_data = False
     for op in program:
+        if not end_of_data:
+            if op.name not in DATA_STATEMENTS:
+                end_of_data = True
+        else:
+            if op.name in DATA_STATEMENTS:
+                emit_error("data statement after instruction", line=op.name.line)
         typecheck_one(op)
 
 

diff --git a/test/test_typechecker.py b/test/test_typechecker.py
@@ -677,3 +677,12 @@ def test_typecheck_multiple_errors():
         call_args = mock_emit_error.call_args_list[2][0]
         assert "INC" in call_args[0]
         assert "too few" in call_args[0]
+
+
+def test_typecheck_data_statement_after_instruction():
+    program = [Op("SET", [R("R1"), 42]), Op(SYM("DLABEL"), [SYM("N")])]
+
+    with patch("hera.utils._emit_msg") as mock_emit_error:
+        typecheck(program)
+        assert mock_emit_error.call_count == 1
+        assert "data statement after instruction" in mock_emit_error.call_args[0][0]