Fix: don't treat the PARAMETER token as a MacroVar start if it's not @ (#1505)

* Fix: don't treat the PARAMETER token as a MacroVar start if it's not @

* Factor out '@' into a constant

Author: georgesittas

sqlmesh/core/dialect.py

@@ -19,6 +19,8 @@
 from sqlmesh.utils.errors import SQLMeshError
 from sqlmesh.utils.pandas import columns_to_types_from_df
 
+SQLMESH_MACRO_PREFIX = "@"
+
 JSON_TYPE = exp.DataType.build("json")
 
 
@@ -147,6 +149,9 @@ def _parse_lambda(self: Parser, alias: bool = False) -> t.Optional[exp.Expressio
 
 
 def _parse_macro(self: Parser, keyword_macro: str = "") -> t.Optional[exp.Expression]:
+    if self._prev.text != SQLMESH_MACRO_PREFIX:
+        return self._parse_parameter()
+
     index = self._index
     field = self._parse_primary() or self._parse_function(functions={}) or self._parse_id_var()
 
@@ -330,7 +335,7 @@ def _parse_table_parts(self: Parser, schema: bool = False) -> exp.Table:
     table = self.__parse_table_parts(schema=schema)  # type: ignore
     table_arg = table.this
 
-    if isinstance(table_arg, exp.Var) and table_arg.name.startswith("@"):
+    if isinstance(table_arg, exp.Var) and table_arg.name.startswith(SQLMESH_MACRO_PREFIX):
         return StagedFilePath(this=MacroVar(this=table_arg.name[1:]))
 
     return table
@@ -640,7 +645,7 @@ def extend_sqlglot() -> None:
             generators.add(dialect.Generator)
 
     for tokenizer in tokenizers:
-        tokenizer.VAR_SINGLE_TOKENS.update("@")
+        tokenizer.VAR_SINGLE_TOKENS.update(SQLMESH_MACRO_PREFIX)
 
     for parser in parsers:
         parser.FUNCTIONS.update({"JINJA": Jinja.from_arg_list, "METRIC": MetricAgg.from_arg_list})

sqlmesh/core/macros.py

@@ -12,6 +12,7 @@
 from sqlglot.helper import csv, ensure_collection
 
 from sqlmesh.core.dialect import (
+    SQLMESH_MACRO_PREFIX,
     MacroDef,
     MacroFunc,
     MacroSQL,
@@ -26,7 +27,7 @@
 
 
 class MacroStrTemplate(Template):
-    delimiter = "@"
+    delimiter = SQLMESH_MACRO_PREFIX
 
 
 EXPRESSIONS_NAME_MAP = {}
@@ -313,7 +314,7 @@ def substitute(
         if isinstance(node, (exp.Identifier, exp.Var)):
             if node.name in args and not isinstance(node.parent, exp.Column):
                 return args[node.name].copy()
-            if "@" in node.name:
+            if SQLMESH_MACRO_PREFIX in node.name:
                 return node.__class__(
                     this=evaluator.template(node.name, {k: v.name for k, v in args.items()})
                 )

tests/core/test_macros.py

@@ -5,7 +5,7 @@
 import pytest
 from sqlglot import exp, parse_one
 
-from sqlmesh.core.dialect import StagedFilePath
+from sqlmesh.core.dialect import MacroVar, StagedFilePath
 from sqlmesh.core.macros import MacroEvaluator, macro
 from sqlmesh.utils.errors import SQLMeshError
 from sqlmesh.utils.metaprogramming import Executable, ExecutableKind
@@ -93,6 +93,9 @@ def test_macro_var(macro_evaluator):
 
         assert "Macro variable 'y' is undefined." in str(ex.value)
 
+    # Parsing a "parameter" like Snowflake's $1 should not produce a MacroVar expression
+    assert parse_one("select $1", read="snowflake").find(MacroVar) is None
+
 
 def test_macro_str_replace(macro_evaluator):
     expression = parse_one("""@'@val1, @val2'""")