Merge pull request #46 from jg-rp/logical-expr

Fix type checks on logical expressions.

Author: jg-rp

CHANGELOG.md

@@ -2,9 +2,14 @@
 
 ## Version 0.10.3 (unreleased)
 
+**Changes**
+
+- Changed the exception raised when attempting to compare a non-singular filter query from `JSONPathSyntaxError` to `JSONPathTypeError`.
+
 **Fixes**
 
 - Fixed handling of relative and root queries when used as arguments to filter functions. Previously, when those queries resulted in an empty node list, we were converting them to an empty regular list before passing it to functions that accept _ValueType_ arguments. Now, in such cases, we convert empty node lists to the special result _Nothing_, which is required by the spec.
+- Fixed well-typedness checks on JSONPath logical expressions (those that involve `&&` or `||`) and non-singular filter queries. Previously we were erroneously applying the checks for comparison expressions to logical expressions too. Now non-singular queries in logical expressions act as an existence test. See [#45] (https://github.com/jg-rp/python-jsonpath/issues/45).
 
 ## Version 0.10.2
 

jsonpath/__about__.py

@@ -1,4 +1,4 @@
 # SPDX-FileCopyrightText: 2023-present James Prior <jamesgr.prior@gmail.com>
 #
 # SPDX-License-Identifier: MIT
-__version__ = "0.10.2"
+__version__ = "0.10.3"

jsonpath/parse.py

@@ -180,7 +180,7 @@ class Parser:
         TOKEN_RE: "=~",
     }
 
-    SINGULAR_QUERY_COMPARISON_OPERATORS = frozenset(
+    COMPARISON_OPERATORS = frozenset(
         [
             "==",
             ">=",
@@ -511,10 +511,7 @@ def parse_infix_expression(
         right = self.parse_filter_selector(stream, precedence)
         operator = self.BINARY_OPERATORS[tok.kind]
 
-        self._raise_for_non_singular_query(left, tok)  # TODO: store tok on expression
-        self._raise_for_non_singular_query(right, tok)
-
-        if operator in self.SINGULAR_QUERY_COMPARISON_OPERATORS:
+        if self.env.well_typed and operator in self.COMPARISON_OPERATORS:
             self._raise_for_non_comparable_function(left, tok)
             self._raise_for_non_comparable_function(right, tok)
 
@@ -666,26 +663,18 @@ def _decode_string_literal(self, token: Token) -> str:
 
         return token.value
 
-    def _raise_for_non_singular_query(
-        self, expr: FilterExpression, token: Token
-    ) -> None:
-        if (
-            self.env.well_typed
-            and isinstance(expr, Path)
-            and not expr.path.singular_query()
-        ):
-            raise JSONPathSyntaxError(
-                "non-singular query is not comparable", token=token
-            )
-
     def _raise_for_non_comparable_function(
         self, expr: FilterExpression, token: Token
     ) -> None:
-        if not self.env.well_typed or not isinstance(expr, FunctionExtension):
-            return
-        func = self.env.function_extensions.get(expr.name)
-        if (
-            isinstance(func, FilterFunction)
-            and func.return_type != ExpressionType.VALUE
-        ):
-            raise JSONPathTypeError(f"result of {expr.name}() is not comparable", token)
+        if isinstance(expr, Path) and not expr.path.singular_query():
+            raise JSONPathTypeError("non-singular query is not comparable", token=token)
+
+        if isinstance(expr, FunctionExtension):
+            func = self.env.function_extensions.get(expr.name)
+            if (
+                isinstance(func, FilterFunction)
+                and func.return_type != ExpressionType.VALUE
+            ):
+                raise JSONPathTypeError(
+                    f"result of {expr.name}() is not comparable", token
+                )

tests/test_env.py

@@ -5,6 +5,7 @@
 import pytest
 
 from jsonpath import JSONPathEnvironment
+from jsonpath import JSONPathTypeError
 
 
 @pytest.fixture()
@@ -170,3 +171,13 @@ class MyJSONPathEnvironment(JSONPathEnvironment):
     data = {"foo": {"a": 1, "b": 2, "c": 3}}
     assert env.findall("$.foo.*~", data) == ["a", "b", "c"]
     assert env.findall("$.foo.*", data) == [1, 2, 3]
+
+
+def test_disable_well_typed_checks() -> None:
+    """Test that we can disable checks for well-typedness."""
+    env = JSONPathEnvironment(well_typed=True)
+    with pytest.raises(JSONPathTypeError):
+        env.compile("$[?@.* > 2]")
+
+    env = JSONPathEnvironment(well_typed=False)
+    env.compile("$[?@.* > 2]")

tests/test_errors.py

@@ -23,3 +23,8 @@ def test_function_missing_param(env: JSONPathEnvironment) -> None:
 def test_function_too_many_params(env: JSONPathEnvironment) -> None:
     with pytest.raises(JSONPathTypeError):
         env.compile("$[?(length(@.a, @.b)==1)]")
+
+
+def test_non_singular_query_is_not_comparable(env: JSONPathEnvironment) -> None:
+    with pytest.raises(JSONPathTypeError):
+        env.compile("$[?@.* > 2]")