Revert "Support passing custom filters with the same name as built-in flags"

Reverted the fix for 🎫`140` released in Mako 1.3.7 as it produced
regressions in existing user code.

This reverts commit f37777c.

Fixes: #415
Change-Id: I0fe9735828fd56bccae3d48bcc5a12b6de4aac40

Author: zzzeek

doc/build/changelog.rst

@@ -11,7 +11,7 @@ Changelog
     :include_notes_from: unreleased
 
 .. changelog::
-    :version: 1.3.7
+    :version: 1.3.7 (yanked)
     :released: Tue Dec 3 2024
 
     .. change::

doc/build/unreleased/415.rst

@@ -0,0 +1,7 @@
+.. change::
+    :tags: bug, lexer
+    :tickets: 415, 140
+
+    Reverted the fix for :ticket:`140` released in Mako 1.3.7 as it produced
+    regressions in existing user code.
+

mako/codegen.py

@@ -16,7 +16,6 @@
 from mako import filters
 from mako import parsetree
 from mako import util
-from mako.filters import DEFAULT_ESCAPE_PREFIX
 from mako.pygen import PythonPrinter
 
 
@@ -27,7 +26,6 @@
 # context itself
 TOPLEVEL_DECLARED = {"UNDEFINED", "STOP_RENDERING"}
 RESERVED_NAMES = {"context", "loop"}.union(TOPLEVEL_DECLARED)
-DEFAULT_ESCAPED_N = "%sn" % DEFAULT_ESCAPE_PREFIX
 
 
 def compile(  # noqa
@@ -524,7 +522,6 @@ def write_variable_declares(self, identifiers, toplevel=False, limit=None):
             self.printer.writeline("loop = __M_loop = runtime.LoopStack()")
 
         for ident in to_write:
-            ident = ident.replace(DEFAULT_ESCAPE_PREFIX, "")
             if ident in comp_idents:
                 comp = comp_idents[ident]
                 if comp.is_block:
@@ -788,48 +785,25 @@ def locate_encode(name):
             else:
                 return filters.DEFAULT_ESCAPES.get(name, name)
 
-        filter_args = set()
-        if DEFAULT_ESCAPED_N not in args:
+        if "n" not in args:
             if is_expression:
                 if self.compiler.pagetag:
                     args = self.compiler.pagetag.filter_args.args + args
-                    filter_args = set(self.compiler.pagetag.filter_args.args)
-                if (
-                    self.compiler.default_filters
-                    and DEFAULT_ESCAPED_N not in args
-                ):
+                if self.compiler.default_filters and "n" not in args:
                     args = self.compiler.default_filters + args
         for e in args:
-            if e == DEFAULT_ESCAPED_N:
-                continue
-
-            if e.startswith(DEFAULT_ESCAPE_PREFIX):
-                render_e = e.replace(DEFAULT_ESCAPE_PREFIX, "")
-                is_default_filter = True
-            else:
-                render_e = e
-                is_default_filter = False
-
             # if filter given as a function, get just the identifier portion
+            if e == "n":
+                continue
             m = re.match(r"(.+?)(\(.*\))", e)
             if m:
-                if not is_default_filter:
-                    ident, fargs = m.group(1, 2)
-                    f = locate_encode(ident)
-                    render_e = f + fargs
-                target = "%s(%s)" % (render_e, target)
-            elif is_default_filter and e not in filter_args:
-                target = "%s(%s) if %s is not UNDEFINED else %s(%s)" % (
-                    render_e,
-                    target,
-                    render_e,
-                    locate_encode(render_e),
-                    target,
-                )
+                ident, fargs = m.group(1, 2)
+                f = locate_encode(ident)
+                e = f + fargs
             else:
-                e = locate_encode(render_e)
+                e = locate_encode(e)
                 assert e is not None
-                target = "%s(%s)" % (e, target)
+            target = "%s(%s)" % (e, target)
         return target
 
     def visitExpression(self, node):

mako/filters.py

@@ -161,6 +161,3 @@ def htmlentityreplace_errors(ex):
     "str": "str",
     "n": "n",
 }
-
-
-DEFAULT_ESCAPE_PREFIX = "__DEFAULT_ESCAPE_"

mako/pyparser.py

@@ -18,8 +18,6 @@
 from mako import compat
 from mako import exceptions
 from mako import util
-from mako.filters import DEFAULT_ESCAPE_PREFIX
-from mako.filters import DEFAULT_ESCAPES
 
 # words that cannot be assigned to (notably
 # smaller than the total keys in __builtins__)
@@ -198,24 +196,9 @@ def visit_Tuple(self, node):
                 p.declared_identifiers
             )
             lui = self.listener.undeclared_identifiers
-            undeclared_identifiers = lui.union(p.undeclared_identifiers)
-            conflict_identifiers = undeclared_identifiers.intersection(
-                DEFAULT_ESCAPES
+            self.listener.undeclared_identifiers = lui.union(
+                p.undeclared_identifiers
             )
-            if conflict_identifiers:
-                _map = {
-                    i: DEFAULT_ESCAPE_PREFIX + i for i in conflict_identifiers
-                }
-                for i, arg in enumerate(self.listener.args):
-                    if arg in _map:
-                        self.listener.args[i] = _map[arg]
-                self.listener.undeclared_identifiers = (
-                    undeclared_identifiers.symmetric_difference(
-                        conflict_identifiers
-                    ).union(_map.values())
-                )
-            else:
-                self.listener.undeclared_identifiers = undeclared_identifiers
 
 
 class ParseFunc(_ast_util.NodeVisitor):

test/test_ast.py

@@ -285,36 +285,16 @@ def test_python_fragment(self):
 
     def test_argument_list(self):
         parsed = ast.ArgumentList(
-            "3, 5, 'hi', g+5, " "context.get('lala')", **exception_kwargs
+            "3, 5, 'hi', x+5, " "context.get('lala')", **exception_kwargs
         )
-        eq_(parsed.undeclared_identifiers, {"g", "context"})
+        eq_(parsed.undeclared_identifiers, {"x", "context"})
         eq_(
             [x for x in parsed.args],
-            ["3", "5", "'hi'", "(g + 5)", "context.get('lala')"],
+            ["3", "5", "'hi'", "(x + 5)", "context.get('lala')"],
         )
 
-        parsed = ast.ArgumentList("m", **exception_kwargs)
-        eq_(parsed.args, ["m"])
-
-    def test_conflict_argument_list(self):
-        parsed = ast.ArgumentList(
-            "x-2, h*2, '(u)', n+5, trim, entity, unicode, decode, str, other",
-            **exception_kwargs,
-        )
-        eq_(
-            parsed.undeclared_identifiers,
-            {
-                "__DEFAULT_ESCAPE_trim",
-                "__DEFAULT_ESCAPE_h",
-                "__DEFAULT_ESCAPE_decode",
-                "__DEFAULT_ESCAPE_unicode",
-                "__DEFAULT_ESCAPE_x",
-                "__DEFAULT_ESCAPE_str",
-                "__DEFAULT_ESCAPE_entity",
-                "__DEFAULT_ESCAPE_n",
-                "other",
-            },
-        )
+        parsed = ast.ArgumentList("h", **exception_kwargs)
+        eq_(parsed.args, ["h"])
 
     def test_function_decl(self):
         """test getting the arguments from a function"""

test/test_filters.py

@@ -453,36 +453,3 @@ def test_capture_ccall(self):
 
         # print t.render()
         assert flatten_result(t.render()) == "this is foo. body: ccall body"
-
-    def test_conflict_filter_ident(self):
-        class h(object):
-            foo = str
-
-        t = Template(
-            """
-X:
-    ${"asdf" | h.foo}
-"""
-        )
-        assert flatten_result(t.render(h=h)) == "X: asdf"
-
-        def h(i):
-            return str(i) + "1"
-
-        t = Template(
-            """
-        ${123 | h}
-"""
-        )
-        assert flatten_result(t.render()) == "123"
-        assert flatten_result(t.render(h=h)) == "1231"
-
-        t = Template(
-            """
-        <%def name="foo()" filter="h">
-            this is foo</%def>
-        ${foo()}
-"""
-        )
-        assert flatten_result(t.render()) == "this is foo"
-        assert flatten_result(t.render(h=h)) == "this is foo1"

test/test_lexer.py

@@ -1543,7 +1543,7 @@ def test_integration(self):
                     Text("    <tr>\n", (14, 1)),
                     ControlLine("for", "for x in j:", False, (15, 1)),
                     Text("            <td>Hello ", (16, 1)),
-                    Expression("x", ["__DEFAULT_ESCAPE_h"], (16, 23)),
+                    Expression("x", ["h"], (16, 23)),
                     Text("</td>\n", (16, 30)),
                     ControlLine("for", "endfor", True, (17, 1)),
                     Text("    </tr>\n", (18, 1)),

test/test_template.py

@@ -1,5 +1,7 @@
 import os
 
+import pytest
+
 from mako import exceptions
 from mako import runtime
 from mako import util
@@ -722,6 +724,27 @@ def handle(context, error):
 
 
 class UndefinedVarsTest(TemplateTest):
+    @pytest.mark.parametrize(
+        "filters",
+        [
+            ["str", "n"],
+            ["n"],
+            ["str", "h"],
+            ["h"],
+            [],
+        ],
+    )
+    def test_140_regression(self, filters):
+        """test #415, regression on #140"""
+
+        t1 = Template(
+            "hello world ${x}",
+            strict_undefined=True,
+            default_filters=filters,
+        )
+
+        t1.render_unicode(x="hi")
+
     def test_undefined(self):
         t = Template(
             """