feat(ir): rewrite and speed up expression repr

The expression `__repr__` is rewritten to be less noisy and more performant.
See https://gist.github.com/gforsyth/1d41488a8680d2dd43bff8a07f1f7931 for details.

ibis/backends/base/sql/compiler/query_builder.py

@@ -178,7 +178,7 @@ def get_result(self):
         return buf.getvalue()
 
 
-class Select(DML, util.CachedEqMixin):
+class Select(DML, util.EqMixin):
 
     """
     A SELECT statement which, after execution, might yield back to the user a

ibis/backends/dask/execution/window.py

@@ -69,7 +69,7 @@ def execute_window_op(
         [
             window.preceding is None,
             window.following is None,
-            window._order_by == [],
+            not window._order_by,
         ]
     ):
         raise NotImplementedError(

ibis/config.py

@@ -3,7 +3,7 @@
 from typing import Any, Callable, Iterator, Optional, Tuple
 
 from pydantic import BaseModel as PydanticBaseModel
-from pydantic import BaseSettings, Field
+from pydantic import BaseSettings, Field, validator
 
 __all__ = [
     "option_context",
@@ -37,13 +37,56 @@ class SQL(BaseModel):
     )
 
 
+class Repr(BaseModel):
+    """Options controlling expression printing."""
+
+    depth: Optional[int] = Field(
+        default=None,
+        description="The maximum number of expression nodes to print when repring.",  # noqa: E501
+    )
+    table_columns: Optional[int] = Field(
+        default=None,
+        description="The number of columns to show in leaf table expressions.",
+    )
+    query_text_length: int = Field(
+        default=80,
+        description="The maximum number of characters to show in the `query` field repr of SQLQueryResult operations.",  # noqa: E501
+    )
+    show_types: bool = Field(
+        default=False,
+        description="Show the inferred type of value expressions in the repr.",
+    )
+
+    @validator("depth")
+    def depth_gt_zero_or_none(cls, depth: Optional[int]) -> Optional[int]:
+        if depth is not None and depth <= 0:
+            raise ValueError("must be None or greater than 0")
+        return depth
+
+    @validator("table_columns")
+    def table_columns_gt_zero_or_none(
+        cls,
+        table_columns: Optional[int],
+    ) -> Optional[int]:
+        if table_columns is not None and table_columns <= 0:
+            raise ValueError("must be None or greater than 0")
+        return table_columns
+
+    @validator("query_text_length")
+    def query_text_length_ge_zero(cls, query_text_length: int) -> int:
+        if query_text_length < 0:
+            raise ValueError("must be non-negative")
+        return query_text_length
+
+
 class Options(BaseSettings):
     """Ibis configuration options."""
 
     interactive: bool = Field(
         default=False,
         description="Show the first few rows of computing an expression when in a repl.",  # noqa: E501
     )
+    repr: Repr = Field(default=Repr(), description=Repr.__doc__)
     verbose: bool = Field(
         default=False,
         description="Run in verbose mode if [`True`][True]",

ibis/expr/datatypes/__init__.py

@@ -62,7 +62,7 @@ def _not_constructible(cls: type[DataType]) -> type[DataType]:
 
 @public
 @_not_constructible
-class DataType(util.CachedEqMixin):
+class DataType(util.EqMixin):
     """Base class for all data types.
 
     [`DataType`][ibis.expr.datatypes.DataType] instances are
@@ -123,24 +123,16 @@ def __repr__(self) -> str:
 
     @cached_property
     def _hash(self) -> int:
-        custom_parts = (getattr(self, slot) for slot in self._fields)
-        return hash((self.__class__, *custom_parts, self.nullable))
+        return hash(
+            (
+                self.__class__,
+                *(getattr(self, slot) for slot in self._fields),
+            )
+        )
 
     def __hash__(self) -> int:
         return self._hash
 
-    def equals(
-        self,
-        other: typing.Any,
-        cache: MutableMapping[Hashable, bool] | None = None,
-    ) -> bool:
-        if not isinstance(other, DataType):
-            raise TypeError(
-                'Comparing datatypes to other types is not allowed. Convert '
-                f'{other!r} to the equivalent DataType instance.'
-            )
-        return super().equals(other, cache=cache)
-
     def __component_eq__(
         self,
         other: DataType,
@@ -698,7 +690,6 @@ def __init__(
         types
             Types of the fields of the struct
         """
-
         names = tuple(names)
         if not names:
             raise ValueError("names must not be empty")
@@ -731,7 +722,7 @@ def from_tuples(
             Struct data type instance
         """
         names, types = zip(*pairs)
-        return cls(list(names), list(map(dtype, types)), nullable=nullable)
+        return cls(names, types, nullable=nullable)
 
     @classmethod
     def from_dict(
@@ -752,7 +743,7 @@ def from_dict(
             Struct data type instance
         """
         names, types = pairs.keys(), pairs.values()
-        return cls(list(names), list(map(dtype, types)), nullable=nullable)
+        return cls(names, types, nullable=nullable)
 
     @property
     def pairs(self) -> Mapping[str, DataType]: