Update like statements to reflect sql behaviors (#91)
* Update like statements to reflect sql behaciors
* Codestyle
* Codestyle
* Handle NotStartsWith
* Update pyiceberg/expressions/parser.py
Co-authored-by: Fokko Driesprong <fokko@apache.org>
* Update tests/expressions/test_parser.py
Co-authored-by: Fokko Driesprong <fokko@apache.org>
---------
Co-authored-by: Fokko Driesprong <fokko@apache.org>
diff --git a/pyiceberg/expressions/parser.py b/pyiceberg/expressions/parser.py
index 4580533..8873907 100644
--- a/pyiceberg/expressions/parser.py
+++ b/pyiceberg/expressions/parser.py
@@ -14,6 +14,7 @@
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
+import re
from decimal import Decimal
from pyparsing import (
@@ -51,7 +52,6 @@
NotIn,
NotNaN,
NotNull,
- NotStartsWith,
Or,
Reference,
StartsWith,
@@ -78,6 +78,8 @@
identifier = Word(alphas, alphanums + "_$").set_results_name("identifier")
column = DelimitedList(identifier, delim=".", combine=False).set_results_name("column")
+like_regex = r'(?P<valid_wildcard>(?<!\\)%$)|(?P<invalid_wildcard>(?<!\\)%)'
+
@column.set_parse_action
def _(result: ParseResults) -> Reference:
@@ -217,12 +219,25 @@
@starts_with.set_parse_action
def _(result: ParseResults) -> BooleanExpression:
- return StartsWith(result.column, result.raw_quoted_string)
+ return _evaluate_like_statement(result)
@not_starts_with.set_parse_action
def _(result: ParseResults) -> BooleanExpression:
- return NotStartsWith(result.column, result.raw_quoted_string)
+ return ~_evaluate_like_statement(result)
+
+
+def _evaluate_like_statement(result: ParseResults) -> BooleanExpression:
+ literal_like: StringLiteral = result.raw_quoted_string
+
+ match = re.search(like_regex, literal_like.value)
+
+ if match and match.groupdict()['invalid_wildcard']:
+ raise ValueError("LIKE expressions only supports wildcard, '%', at the end of a string")
+ elif match and match.groupdict()['valid_wildcard']:
+ return StartsWith(result.column, StringLiteral(literal_like.value[:-1].replace('\\%', '%')))
+ else:
+ return EqualTo(result.column, StringLiteral(literal_like.value.replace('\\%', '%')))
predicate = (comparison | in_check | null_check | nan_check | starts_check | boolean).set_results_name("predicate")
diff --git a/tests/expressions/test_parser.py b/tests/expressions/test_parser.py
index 65415f2..8257710 100644
--- a/tests/expressions/test_parser.py
+++ b/tests/expressions/test_parser.py
@@ -168,12 +168,30 @@
) == parser.parse("foo is not null and foo < 5 or (foo > 10 and foo < 100 and bar is null)")
+def test_like_equality() -> None:
+ assert EqualTo("foo", "data") == parser.parse("foo LIKE 'data'")
+ assert EqualTo("foo", "data%") == parser.parse("foo LIKE 'data\\%'")
+
+
def test_starts_with() -> None:
- assert StartsWith("foo", "data") == parser.parse("foo LIKE 'data'")
+ assert StartsWith("foo", "data") == parser.parse("foo LIKE 'data%'")
+ assert StartsWith("foo", "some % data") == parser.parse("foo LIKE 'some \\% data%'")
+ assert StartsWith("foo", "some data%") == parser.parse("foo LIKE 'some data\\%%'")
+
+
+def test_invalid_likes() -> None:
+ invalid_statements = ["foo LIKE '%data%'", "foo LIKE 'da%ta'", "foo LIKE '%data'"]
+
+ for statement in invalid_statements:
+ with pytest.raises(ValueError) as exc_info:
+ parser.parse(statement)
+
+ assert "LIKE expressions only supports wildcard, '%', at the end of a string" in str(exc_info)
def test_not_starts_with() -> None:
- assert NotStartsWith("foo", "data") == parser.parse("foo NOT LIKE 'data'")
+ assert NotEqualTo("foo", "data") == parser.parse("foo NOT LIKE 'data'")
+ assert NotStartsWith("foo", "data") == parser.parse("foo NOT LIKE 'data%'")
def test_with_function() -> None:
