From 24f283f4304854648f48019d3d0b48f9b701652c Mon Sep 17 00:00:00 2001
From: dnwpark <dnwpark@protonmail.com>
Date: Tue, 4 Feb 2025 10:04:53 -0500
Subject: [PATCH] Fix inline functions substituting parameters from hidden
 nodes. (#8288)

A function body may be a statement which contains references to a parent statement. Ensure that this parent's parameters are not substituted while inlining the function parameters.
---
 edb/common/ast/transformer.py         | 12 +++++++++
 edb/edgeql/compiler/func.py           |  4 +++
 tests/test_edgeql_functions_inline.py | 39 +++++++++++++++++++++++++++
 3 files changed, 55 insertions(+)

diff --git a/edb/common/ast/transformer.py b/edb/common/ast/transformer.py
index 30d11671c79..c3e893d5beb 100644
--- a/edb/common/ast/transformer.py
+++ b/edb/common/ast/transformer.py
@@ -64,6 +64,12 @@ def generic_visit(self, node):
             changes = {}
 
             for field, old_value in base.iter_fields(node, include_meta=False):
+                field_spec = node._fields[field]
+                if self.skip_hidden and field_spec.hidden:
+                    continue
+                if field in self.extra_skips:
+                    continue
+
                 old_value = getattr(node, field, None)
 
                 if typeutils.is_container(old_value):
@@ -79,6 +85,12 @@ def generic_visit(self, node):
 
         else:
             for field, old_value in base.iter_fields(node, include_meta=False):
+                field_spec = node._fields[field]
+                if self.skip_hidden and field_spec.hidden:
+                    continue
+                if field in self.extra_skips:
+                    continue
+
                 old_value = getattr(node, field, None)
 
                 if typeutils.is_container(old_value):
diff --git a/edb/edgeql/compiler/func.py b/edb/edgeql/compiler/func.py
index 736220333a2..19f46345346 100644
--- a/edb/edgeql/compiler/func.py
+++ b/edb/edgeql/compiler/func.py
@@ -479,6 +479,10 @@ def compile_FunctionCall(
 
 class ArgumentInliner(ast.NodeTransformer):
 
+    # Don't look through hidden nodes, they may contain references to nodes
+    # which should not be modified. For example, irast.Stmt.parent_stmt.
+    skip_hidden = True
+
     mapped_args: dict[irast.PathId, irast.PathId]
     inlined_arg_keys: list[int | str]
 
diff --git a/tests/test_edgeql_functions_inline.py b/tests/test_edgeql_functions_inline.py
index 14f0bf13241..9487ca4a87f 100644
--- a/tests/test_edgeql_functions_inline.py
+++ b/tests/test_edgeql_functions_inline.py
@@ -3133,6 +3133,45 @@ async def test_edgeql_functions_inline_nested_basic_20(self):
             sort=True,
         )
 
+    async def test_edgeql_functions_inline_nested_basic_21(self):
+        # Inner function body is a statement with a parent statement
+        #
+        # A function body may be a statement which contains references to a
+        # parent statement. Ensure that this parent's parameters are not
+        # substituted while inlining the function parameters.
+        #
+        # In this case the outer function's `for` contains the parameter `x`
+        # which is at risk of being substituted when the inner function
+        # inlines its parameters.
+        await self.con.execute('''
+            create function inner(x: int64) -> int64 {
+                set is_inlined := true;
+                using (select x)
+            };
+            create function foo(x: int64) -> set of int64 {
+                set is_inlined := true;
+                using (for y in {x, x + 1, x + 2} union (inner(y)));
+            };
+        ''')
+        await self.assert_query_result(
+            'select foo(<int64>{})',
+            [],
+        )
+        await self.assert_query_result(
+            'select foo(10)',
+            [10, 11, 12],
+        )
+        await self.assert_query_result(
+            'select foo({10, 20, 30})',
+            [10, 11, 12, 20, 21, 22, 30, 31, 32],
+            sort=True,
+        )
+        await self.assert_query_result(
+            'for x in {10, 20, 30} union (select foo(x))',
+            [10, 11, 12, 20, 21, 22, 30, 31, 32],
+            sort=True,
+        )
+
     async def test_edgeql_functions_inline_nested_array_01(self):
         # Return array from inner function
         await self.con.execute('''