API: split out MLIR-independent printing into BasePrinter and use in …

…STIM [NFC] (#3613)

I'd also like to use the indentation logic in ASL, WGSL, and the
assembly dialects, PRs incoming.

tests/test_printer.py

@@ -952,43 +952,3 @@ def test_get_printed_name():
     printed = StringIO()
     picked_name = Printer(printed).print_ssa_value(val)
     assert f"%{picked_name}" == printed.getvalue()
-
-
-def test_indented():
-    output = StringIO()
-    printer = Printer(stream=output)
-    printer.print("\n{")
-    with printer.indented():
-        printer.print("\nhello\nhow are you?")
-        printer.print("\n(")
-        with printer.indented():
-            printer.print("\nfoo,")
-            printer.print("\nbar,")
-            printer.print("\n")
-            printer.print_string("test\nraw print!", indent=0)
-            printer.print_string("\ndifferent indent level", indent=4)
-        printer.print("\n)")
-    printer.print("\n}")
-    printer.print("\n[")
-    with printer.indented(amount=3):
-        printer.print("\nbaz")
-    printer.print("\n]\n")
-
-    EXPECTED = """
-{
-  hello
-  how are you?
-  (
-    foo,
-    bar,
-    test
-raw print!
-        different indent level
-  )
-}
-[
-      baz
-]
-"""
-
-    assert output.getvalue() == EXPECTED

tests/utils/test_base_printer.py

@@ -0,0 +1,43 @@
+from io import StringIO
+
+from xdsl.utils.base_printer import BasePrinter
+
+
+def test_indented():
+    output = StringIO()
+    printer = BasePrinter(stream=output)
+    printer.print_string("\n{")
+    with printer.indented():
+        printer.print_string("\nhello\nhow are you?")
+        printer.print_string("\n(")
+        with printer.indented():
+            printer.print_string("\nfoo,")
+            printer.print_string("\nbar,")
+            printer.print_string("\n")
+            printer.print_string("test\nraw print!", indent=0)
+            printer.print_string("\ndifferent indent level", indent=4)
+        printer.print_string("\n)")
+    printer.print_string("\n}")
+    printer.print_string("\n[")
+    with printer.indented(amount=3):
+        printer.print_string("\nbaz")
+    printer.print_string("\n]\n")
+
+    EXPECTED = """
+{
+  hello
+  how are you?
+  (
+    foo,
+    bar,
+    test
+raw print!
+        different indent level
+  )
+}
+[
+      baz
+]
+"""
+
+    assert output.getvalue() == EXPECTED

xdsl/dialects/stim/stim_printer_parser.py

@@ -1,25 +1,20 @@
-import abc
-from collections.abc import Callable, Iterable
-from contextlib import contextmanager
-from dataclasses import dataclass, field
-from typing import Any, TypeVar, cast
-
-from xdsl.dialects.builtin import ArrayAttr, FloatData, IntAttr
-from xdsl.ir import Attribute, Operation
-
 """
 This file implements a printer that prints to the .stim file format.
 Full documentation can be found here: https://github.com/quantumlib/Stim/blob/main/doc/file_format_stim_circuit.md
 """
 
+import abc
+from contextlib import contextmanager
+from dataclasses import dataclass
+from typing import cast
 
-@dataclass(eq=False, repr=False)
-class StimPrinter:
-    stream: Any | None = field(default=None)
+from xdsl.dialects.builtin import ArrayAttr, FloatData, IntAttr
+from xdsl.ir import Attribute, Operation
+from xdsl.utils.base_printer import BasePrinter
 
-    def print_string(self, text: str) -> None:
-        print(text, end="", file=self.stream)
 
+@dataclass(eq=False, repr=False)
+class StimPrinter(BasePrinter):
     @contextmanager
     def in_braces(self):
         self.print_string("{")
@@ -32,16 +27,6 @@ def in_parens(self):
         yield
         self.print_string(") ")
 
-    T = TypeVar("T")
-
-    def print_list(
-        self, elems: Iterable[T], print_fn: Callable[[T], Any], delimiter: str = ", "
-    ) -> None:
-        for i, elem in enumerate(elems):
-            if i:
-                self.print_string(delimiter)
-            print_fn(elem)
-
     def print_attribute(self, attribute: Attribute) -> None:
         if isinstance(attribute, ArrayAttr):
             attribute = cast(ArrayAttr[Attribute], attribute)

xdsl/printer.py

@@ -8,8 +8,6 @@
 from itertools import chain
 from typing import Any, TypeVar, cast
 
-from typing_extensions import deprecated
-
 from xdsl.dialects.builtin import (
     AffineMapAttr,
     AffineSetAttr,
@@ -68,6 +66,7 @@
     TypedAttribute,
 )
 from xdsl.traits import IsolatedFromAbove, IsTerminator
+from xdsl.utils.base_printer import BasePrinter
 from xdsl.utils.bitwise_casts import (
     convert_f16_to_u16,
     convert_f32_to_u32,
@@ -76,18 +75,14 @@
 from xdsl.utils.diagnostic import Diagnostic
 from xdsl.utils.mlir_lexer import MLIRLexer
 
-indentNumSpaces = 2
-
 
 @dataclass(eq=False, repr=False)
-class Printer:
-    stream: Any | None = field(default=None)
+class Printer(BasePrinter):
     print_generic_format: bool = field(default=False)
     print_properties_as_attributes: bool = field(default=False)
     print_debuginfo: bool = field(default=False)
     diagnostic: Diagnostic = field(default_factory=Diagnostic)
 
-    _indent: int = field(default=0, init=False)
     _ssa_values: dict[SSAValue, str] = field(default_factory=dict, init=False)
     """
     maps SSA Values to their "allocated" names
@@ -100,11 +95,6 @@ class Printer:
     )
     _next_valid_name_id: list[int] = field(default_factory=lambda: [0], init=False)
     _next_valid_block_id: list[int] = field(default_factory=lambda: [0], init=False)
-    _current_line: int = field(default=0, init=False)
-    _current_column: int = field(default=0, init=False)
-    _next_line_callback: list[Callable[[], None]] = field(
-        default_factory=list, init=False
-    )
 
     @property
     def ssa_names(self):
@@ -148,114 +138,9 @@ def print(self, *argv: Any) -> None:
             text = str(arg)
             self.print_string(text)
 
-    @deprecated("Please use `printer.print_strint(text, indent=0)`")
-    def print_string_raw(self, text: str) -> None:
-        """
-        Prints a string to the printer's output, without taking
-        indentation into account.
-        """
-        self.print_string(text, indent=0)
-
-    def print_string(self, text: str, *, indent: int | None = None) -> None:
-        """
-        Prints a string to the printer's output.
-
-        This function takes into account indentation level when
-        printing new lines.
-        If the indentation level is specified as 0, the string is printed as-is, if `None`
-        then the `Printer` instance's indentation level is used.
-        """
-
-        num_newlines = text.count("\n")
-
-        if not num_newlines:
-            self._current_column += len(text)
-            print(text, end="", file=self.stream)
-            return
-
-        indent = self._indent if indent is None else indent
-        lines = text.split("\n")
-
-        if indent == 0 and not self._next_line_callback:
-            # No indent and no callback to print after the next newline, the text
-            # can be printed directly.
-            self._current_line += num_newlines
-            self._current_column = len(lines[-1])
-            print(text, end="", file=self.stream)
-            return
-
-        # Line and column information is not computed ahead of time
-        # as indent-aware newline printing may use it as part of
-        # callbacks.
-        print(lines[0], end="", file=self.stream)
-        self._current_column += len(lines[0])
-        for line in lines[1:]:
-            self._print_new_line(indent=indent)
-            print(line, end="", file=self.stream)
-            self._current_column += len(line)
-
-    @contextmanager
-    def indented(self, amount: int = 1):
-        """
-        Increases the indentation level by the provided amount
-        for the duration of the context.
-
-        Only affects new lines printed within the context.
-        """
-
-        self._indent += amount
-        try:
-            yield
-        finally:
-            self._indent -= amount
-
-    def _add_message_on_next_line(self, message: str, begin_pos: int, end_pos: int):
-        """Add a message that will be displayed on the next line."""
-
-        def callback(indent: int = self._indent):
-            self._print_message(message, begin_pos, end_pos, indent)
-
-        self._next_line_callback.append(callback)
-
-    def _print_message(
-        self, message: str, begin_pos: int, end_pos: int, indent: int | None = None
-    ):
-        """
-        Print a message.
-        This is expected to be called at the beginning of a new line and to create a new
-        line at the end.
-        The span of the message to be underlined is represented as [begin_pos, end_pos).
-        """
-        indent = self._indent if indent is None else indent
-        indent_size = indent * indentNumSpaces
-        self.print_string(" " * indent_size)
-        message_end_pos = max(map(len, message.split("\n"))) + indent_size + 2
-        first_line = (
-            (begin_pos - indent_size) * "-"
-            + (end_pos - begin_pos) * "^"
-            + (max(message_end_pos, end_pos) - end_pos) * "-"
-        )
-        self.print_string(first_line)
-        self._print_new_line(indent=indent, print_message=False)
-        for message_line in message.split("\n"):
-            self.print_string("| ")
-            self.print_string(message_line)
-            self._print_new_line(indent=indent, print_message=False)
-        self.print_string("-" * (max(message_end_pos, end_pos) - indent_size))
-        self._print_new_line(indent=0, print_message=False)
-
-    T = TypeVar("T")
     K = TypeVar("K")
     V = TypeVar("V")
 
-    def print_list(
-        self, elems: Iterable[T], print_fn: Callable[[T], Any], delimiter: str = ", "
-    ) -> None:
-        for i, elem in enumerate(elems):
-            if i:
-                self.print_string(delimiter)
-            print_fn(elem)
-
     def print_dictionary(
         self,
         elems: dict[K, V],
@@ -270,22 +155,6 @@ def print_dictionary(
             self.print_string("=")
             print_value(value)
 
-    def _print_new_line(
-        self, indent: int | None = None, print_message: bool = True
-    ) -> None:
-        indent = self._indent if indent is None else indent
-        # Prints a newline, bypassing the `print_string` method
-        print(file=self.stream)
-        self._current_line += 1
-        if print_message:
-            for callback in self._next_line_callback:
-                callback()
-            self._next_line_callback = []
-        num_spaces = indent * indentNumSpaces
-        # Prints indentation, bypassing the `print_string` method
-        print(" " * num_spaces, end="", file=self.stream)
-        self._current_column = num_spaces
-
     def _get_new_valid_name_id(self) -> str:
         self._next_valid_name_id[-1] += 1
         return str(self._next_valid_name_id[-1] - 1)