Fix interaction of implicit limit with explicit OFFSET (#7509)

Currently, we will inject a LIMIT at any exposed SELECT, which results
in us applying implicit LIMIT before OFFSET, which is wrong.

Drop the injection inside of SelectStmt compilation and inject the
LIMIT at the top-level instead directly

Fixes #3627.

edb/edgeql/compiler/__init__.py

@@ -275,6 +275,10 @@ def compile_ast_to_ir(
 
     ctx = stmtctx_mod.init_context(schema=schema, options=options)
 
+    if isinstance(tree, qlast.Expr) and ctx.implicit_limit:
+        tree = qlast.SelectQuery(result=tree, implicit=True)
+        tree.limit = qlast.Constant.integer(ctx.implicit_limit)
+
     if not script_info:
         script_info = stmtctx_mod.preprocess_script([tree], ctx=ctx)
 

edb/edgeql/compiler/stmt.py

@@ -127,14 +127,6 @@ def compile_SelectQuery(
             )
         )
 
-        if (
-            (ctx.expr_exposed or sctx.stmt is ctx.toplevel_stmt)
-            and ctx.implicit_limit
-            and expr.limit is None
-            and not ctx.inhibit_implicit_limit
-        ):
-            expr.limit = qlast.Constant.integer(ctx.implicit_limit)
-
         stmt.result = compile_result_clause(
             expr.result,
             view_scls=ctx.view_scls,

edb/edgeql/compiler/viewgen.py

@@ -1534,7 +1534,6 @@ def _normalize_view_ptr_expr(
 
             if (
                 (ctx.expr_exposed or ctx.stmt is ctx.toplevel_stmt)
-                and not qlexpr.limit
                 and ctx.implicit_limit
                 and not base_is_singleton
             ):
@@ -1659,10 +1658,6 @@ def _normalize_view_ptr_expr(
         if (
             (ctx.expr_exposed or ctx.stmt is ctx.toplevel_stmt)
             and ctx.implicit_limit
-            and isinstance(qlexpr, (
-                qlast.SelectQuery, qlast.DeleteQuery, qlast.ShapeElement
-            ))
-            and not qlexpr.limit
         ):
             qlexpr = qlast.SelectQuery(result=qlexpr, implicit=True)
             qlexpr.limit = qlast.Constant.integer(ctx.implicit_limit)

tests/test_edgeql_scope.py

@@ -4177,3 +4177,120 @@ async def test_edgeql_scope_mat_issue_6060(self):
             ''',
             [{"minCost": 1}, {"minCost": 1}, {"minCost": 1}, {"minCost": 2}],
         )
+
+    async def test_edgeql_scope_implicit_limit_01(self):
+        # implicit limit should interact correctly with offset
+        await self.assert_query_result(
+            r'''
+                select Card { name } order by .name offset 3
+            ''',
+            [
+                {"name": "Dwarf"},
+                {"name": "Giant eagle"},
+                {"name": "Giant turtle"},
+                {"name": "Golem"},
+            ],
+            implicit_limit=4,
+        )
+
+        await self.assert_query_result(
+            r'''
+            with W := Card
+            select W { name } order by .name offset 3;
+            ''',
+            [
+                {"name": "Dwarf"},
+                {"name": "Giant eagle"},
+                {"name": "Giant turtle"},
+                {"name": "Golem"},
+            ],
+            implicit_limit=4,
+        )
+
+        await self.assert_query_result(
+            r'''
+                select Card { name } order by .name offset 3 limit 2
+            ''',
+            [
+                {"name": "Dwarf"},
+                {"name": "Giant eagle"},
+            ],
+            implicit_limit=4,
+        )
+
+        await self.assert_query_result(
+            r'''
+            select User { deck: {name} order by .name offset 3 }
+            filter .name = 'Carol';
+            ''',
+            [
+                {
+                    "deck": [
+                        {"name": "Giant eagle"},
+                        {"name": "Giant turtle"},
+                        {"name": "Golem"},
+                    ]
+                }
+            ],
+            implicit_limit=3,
+        )
+
+    async def test_edgeql_scope_implicit_limit_02(self):
+        # explicit limit shouldn't override implicit
+        await self.assert_query_result(
+            r'''
+            select User { deck: {name} order by .name offset 3 limit 100}
+            filter .name = 'Carol';
+            ''',
+            [
+                {
+                    "deck": [
+                        {"name": "Giant eagle"},
+                        {"name": "Giant turtle"},
+                        {"name": "Golem"},
+                    ]
+                }
+            ],
+            implicit_limit=3,
+        )
+
+        await self.assert_query_result(
+            r'''
+            select User { cards := (
+                select .deck {name} order by .name offset 3 limit 100)}
+            filter .name = 'Carol';
+            ''',
+            [
+                {
+                    "cards": [
+                        {"name": "Giant eagle"},
+                        {"name": "Giant turtle"},
+                        {"name": "Golem"},
+                    ]
+                }
+            ],
+            implicit_limit=3,
+        )
+
+        await self.assert_query_result(
+            r'''
+                select Card { name } order by .name offset 3 limit 100
+            ''',
+            [
+                {"name": "Dwarf"},
+                {"name": "Giant eagle"},
+                {"name": "Giant turtle"},
+                {"name": "Golem"},
+            ],
+            implicit_limit=4,
+        )
+
+        await self.assert_query_result(
+            r'''
+                select Card { name } order by .name offset 3 limit 1
+            ''',
+            [
+                {"name": "Dwarf"},
+            ],
+            implicit_limit=4,
+        )