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969 lines
28 KiB
Rust
969 lines
28 KiB
Rust
//! Infrastructure for code formatting
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//!
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//! This module defines [`FormatElement`], an IR to format code documents and provides a means to print
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//! such a document to a string. Objects that know how to format themselves implement the [Format] trait.
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//!
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//! ## Formatting Traits
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//!
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//! * [`Format`]: Implemented by objects that can be formatted.
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//! * [`FormatRule`]: Rule that knows how to format an object of another type. Useful in the situation where
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//! it's necessary to implement [Format] on an object from another crate. This module defines the
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//! [`FormatRefWithRule`] and [`FormatOwnedWithRule`] structs to pass an item with its corresponding rule.
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//! * [`FormatWithRule`] implemented by objects that know how to format another type. Useful for implementing
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//! some reusable formatting logic inside of this module if the type itself doesn't implement [Format]
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//!
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//! ## Formatting Macros
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//!
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//! This crate defines two macros to construct the IR. These are inspired by Rust's `fmt` macros
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//! * [`format!`]: Formats a formattable object
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//! * [`format_args!`]: Concatenates a sequence of Format objects.
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//! * [`write!`]: Writes a sequence of formattable objects into an output buffer.
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mod arguments;
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mod buffer;
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mod builders;
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pub mod diagnostics;
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pub mod format_element;
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mod format_extensions;
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pub mod formatter;
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pub mod group_id;
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pub mod macros;
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pub mod prelude;
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pub mod printer;
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mod source_code;
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use crate::formatter::Formatter;
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use crate::group_id::UniqueGroupIdBuilder;
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use crate::prelude::TagKind;
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use std::fmt;
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use std::fmt::{Debug, Display};
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use std::marker::PhantomData;
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use std::num::{NonZeroU16, NonZeroU8, TryFromIntError};
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use crate::format_element::document::Document;
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use crate::printer::{Printer, PrinterOptions};
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pub use arguments::{Argument, Arguments};
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pub use buffer::{
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Buffer, BufferExtensions, BufferSnapshot, Inspect, RemoveSoftLinesBuffer, VecBuffer,
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};
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pub use builders::BestFitting;
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pub use source_code::{SourceCode, SourceCodeSlice};
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pub use crate::diagnostics::{ActualStart, FormatError, InvalidDocumentError, PrintError};
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pub use format_element::{normalize_newlines, FormatElement, LINE_TERMINATORS};
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pub use group_id::GroupId;
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use ruff_macros::CacheKey;
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use ruff_text_size::{TextLen, TextRange, TextSize};
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#[derive(Debug, Eq, PartialEq, Clone, Copy, Hash, CacheKey)]
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#[cfg_attr(
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feature = "serde",
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derive(serde::Serialize, serde::Deserialize),
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serde(rename_all = "kebab-case")
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)]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
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#[derive(Default)]
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pub enum IndentStyle {
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/// Use tabs to indent code.
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#[default]
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Tab,
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/// Use [`IndentWidth`] spaces to indent code.
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Space,
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}
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impl IndentStyle {
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/// Returns `true` if this is an [`IndentStyle::Tab`].
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pub const fn is_tab(&self) -> bool {
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matches!(self, IndentStyle::Tab)
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}
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/// Returns `true` if this is an [`IndentStyle::Space`].
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pub const fn is_space(&self) -> bool {
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matches!(self, IndentStyle::Space)
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}
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}
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impl std::fmt::Display for IndentStyle {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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match self {
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IndentStyle::Tab => std::write!(f, "tab"),
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IndentStyle::Space => std::write!(f, "space"),
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}
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}
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}
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/// The visual width of a indentation.
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///
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/// Determines the visual width of a tab character (`\t`) and the number of
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/// spaces per indent when using [`IndentStyle::Space`].
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#[derive(Clone, Copy, Debug, Eq, PartialEq, CacheKey)]
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#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
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pub struct IndentWidth(NonZeroU8);
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impl IndentWidth {
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/// Return the numeric value for this [`LineWidth`]
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pub const fn value(&self) -> u32 {
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self.0.get() as u32
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}
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}
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impl Default for IndentWidth {
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fn default() -> Self {
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Self(NonZeroU8::new(2).unwrap())
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}
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}
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impl Display for IndentWidth {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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Display::fmt(&self.0, f)
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}
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}
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impl TryFrom<u8> for IndentWidth {
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type Error = TryFromIntError;
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fn try_from(value: u8) -> Result<Self, Self::Error> {
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NonZeroU8::try_from(value).map(Self)
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}
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}
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impl From<NonZeroU8> for IndentWidth {
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fn from(value: NonZeroU8) -> Self {
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Self(value)
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}
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}
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/// The maximum visual width to which the formatter should try to limit a line.
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#[derive(Clone, Copy, Debug, Eq, PartialEq, CacheKey)]
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#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
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pub struct LineWidth(NonZeroU16);
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impl LineWidth {
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/// Return the numeric value for this [`LineWidth`]
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pub const fn value(&self) -> u16 {
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self.0.get()
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}
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}
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impl Default for LineWidth {
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fn default() -> Self {
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Self(NonZeroU16::new(80).unwrap())
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}
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}
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impl Display for LineWidth {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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Display::fmt(&self.0, f)
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}
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}
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impl TryFrom<u16> for LineWidth {
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type Error = TryFromIntError;
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fn try_from(value: u16) -> Result<LineWidth, Self::Error> {
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NonZeroU16::try_from(value).map(LineWidth)
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}
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}
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impl From<LineWidth> for u16 {
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fn from(value: LineWidth) -> Self {
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value.0.get()
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}
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}
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impl From<LineWidth> for u32 {
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fn from(value: LineWidth) -> Self {
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u32::from(value.0.get())
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}
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}
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impl From<NonZeroU16> for LineWidth {
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fn from(value: NonZeroU16) -> Self {
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Self(value)
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}
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}
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/// Context object storing data relevant when formatting an object.
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pub trait FormatContext {
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type Options: FormatOptions;
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/// Returns the formatting options
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fn options(&self) -> &Self::Options;
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/// Returns the source code from the document that gets formatted.
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fn source_code(&self) -> SourceCode;
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}
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/// Options customizing how the source code should be formatted.
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pub trait FormatOptions {
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/// The indent style.
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fn indent_style(&self) -> IndentStyle;
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/// The visual width of an indent
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fn indent_width(&self) -> IndentWidth;
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/// What's the max width of a line. Defaults to 80.
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fn line_width(&self) -> LineWidth;
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/// Derives the print options from the these format options
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fn as_print_options(&self) -> PrinterOptions;
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}
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#[derive(Debug, Default, Eq, PartialEq)]
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pub struct SimpleFormatContext {
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options: SimpleFormatOptions,
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source_code: String,
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}
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impl SimpleFormatContext {
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pub fn new(options: SimpleFormatOptions) -> Self {
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Self {
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options,
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source_code: String::new(),
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}
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}
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#[must_use]
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pub fn with_source_code(mut self, code: &str) -> Self {
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self.source_code = String::from(code);
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self
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}
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}
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impl FormatContext for SimpleFormatContext {
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type Options = SimpleFormatOptions;
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fn options(&self) -> &Self::Options {
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&self.options
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}
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fn source_code(&self) -> SourceCode {
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SourceCode::new(&self.source_code)
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}
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}
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#[derive(Debug, Default, Eq, PartialEq, Clone)]
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pub struct SimpleFormatOptions {
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pub indent_style: IndentStyle,
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pub indent_width: IndentWidth,
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pub line_width: LineWidth,
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}
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impl FormatOptions for SimpleFormatOptions {
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fn indent_style(&self) -> IndentStyle {
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self.indent_style
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}
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fn indent_width(&self) -> IndentWidth {
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self.indent_width
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}
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fn line_width(&self) -> LineWidth {
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self.line_width
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}
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fn as_print_options(&self) -> PrinterOptions {
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PrinterOptions {
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line_width: self.line_width,
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indent_style: self.indent_style,
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indent_width: self.indent_width,
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..PrinterOptions::default()
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}
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}
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}
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/// Lightweight sourcemap marker between source and output tokens
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#[derive(Debug, Copy, Clone, Eq, PartialEq)]
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#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
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pub struct SourceMarker {
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/// Position of the marker in the original source
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pub source: TextSize,
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/// Position of the marker in the output code
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pub dest: TextSize,
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}
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#[derive(Debug, Clone, Eq, PartialEq)]
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pub struct Formatted<Context> {
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document: Document,
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context: Context,
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}
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impl<Context> Formatted<Context> {
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pub fn new(document: Document, context: Context) -> Self {
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Self { document, context }
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}
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/// Returns the context used during formatting.
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pub fn context(&self) -> &Context {
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&self.context
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}
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/// Returns the formatted document.
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pub fn document(&self) -> &Document {
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&self.document
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}
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/// Consumes `self` and returns the formatted document.
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pub fn into_document(self) -> Document {
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self.document
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}
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}
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impl<Context> Formatted<Context>
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where
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Context: FormatContext,
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{
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pub fn print(&self) -> PrintResult<Printed> {
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let printer = self.create_printer();
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printer.print(&self.document)
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}
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pub fn print_with_indent(&self, indent: u16) -> PrintResult<Printed> {
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let printer = self.create_printer();
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printer.print_with_indent(&self.document, indent)
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}
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fn create_printer(&self) -> Printer {
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let source_code = self.context.source_code();
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let print_options = self.context.options().as_print_options();
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Printer::new(source_code, print_options)
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}
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}
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impl<Context> Display for Formatted<Context>
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where
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Context: FormatContext,
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{
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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std::fmt::Display::fmt(&self.document.display(self.context.source_code()), f)
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}
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}
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pub type PrintResult<T> = Result<T, PrintError>;
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#[derive(Debug, Clone, Eq, PartialEq)]
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#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
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pub struct Printed {
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code: String,
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range: Option<TextRange>,
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sourcemap: Vec<SourceMarker>,
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verbatim_ranges: Vec<TextRange>,
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}
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impl Printed {
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pub fn new(
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code: String,
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range: Option<TextRange>,
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sourcemap: Vec<SourceMarker>,
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verbatim_source: Vec<TextRange>,
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) -> Self {
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Self {
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code,
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range,
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sourcemap,
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verbatim_ranges: verbatim_source,
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}
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}
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/// Construct an empty formatter result
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pub fn new_empty() -> Self {
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Self {
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code: String::new(),
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range: None,
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sourcemap: Vec::new(),
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verbatim_ranges: Vec::new(),
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}
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}
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/// Range of the input source file covered by this formatted code,
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/// or None if the entire file is covered in this instance
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pub fn range(&self) -> Option<TextRange> {
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self.range
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}
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/// Returns a list of [`SourceMarker`] mapping byte positions
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/// in the output string to the input source code.
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/// It's not guaranteed that the markers are sorted by source position.
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pub fn sourcemap(&self) -> &[SourceMarker] {
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&self.sourcemap
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}
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/// Returns a list of [`SourceMarker`] mapping byte positions
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/// in the output string to the input source code, consuming the result
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pub fn into_sourcemap(self) -> Vec<SourceMarker> {
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self.sourcemap
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}
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/// Takes the list of [`SourceMarker`] mapping byte positions in the output string
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/// to the input source code.
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pub fn take_sourcemap(&mut self) -> Vec<SourceMarker> {
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std::mem::take(&mut self.sourcemap)
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}
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/// Access the resulting code, borrowing the result
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pub fn as_code(&self) -> &str {
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&self.code
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}
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/// Access the resulting code, consuming the result
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pub fn into_code(self) -> String {
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self.code
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}
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/// The text in the formatted code that has been formatted as verbatim.
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pub fn verbatim(&self) -> impl Iterator<Item = (TextRange, &str)> {
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self.verbatim_ranges
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.iter()
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.map(|range| (*range, &self.code[*range]))
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}
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/// Ranges of the formatted code that have been formatted as verbatim.
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pub fn verbatim_ranges(&self) -> &[TextRange] {
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&self.verbatim_ranges
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}
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/// Takes the ranges of nodes that have been formatted as verbatim, replacing them with an empty list.
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pub fn take_verbatim_ranges(&mut self) -> Vec<TextRange> {
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std::mem::take(&mut self.verbatim_ranges)
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}
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/// Slices the formatted code to the sub-slices that covers the passed `source_range` in `source`.
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///
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/// The implementation uses the source map generated during formatting to find the closest range
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/// in the formatted document that covers `source_range` or more. The returned slice
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/// matches the `source_range` exactly (except indent, see below) if the formatter emits [`FormatElement::SourcePosition`] for
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/// the range's offsets.
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///
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/// ## Indentation
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/// The indentation before `source_range.start` is replaced with the indentation returned by the formatter
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/// to fix up incorrectly intended code.
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///
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/// Returns the entire document if the source map is empty.
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///
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/// # Panics
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/// If `source_range` points to offsets that are not in the bounds of `source`.
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#[must_use]
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pub fn slice_range(self, source_range: TextRange, source: &str) -> PrintedRange {
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let mut start_marker: Option<SourceMarker> = None;
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let mut end_marker: Option<SourceMarker> = None;
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// Note: The printer can generate multiple source map entries for the same source position.
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// For example if you have:
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// * token("a + b")
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// * `source_position(276)`
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// * `token(")")`
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// * `source_position(276)`
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// * `hard_line_break`
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// The printer uses the source position 276 for both the tokens `)` and the `\n` because
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// there were multiple `source_position` entries in the IR with the same offset.
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// This can happen if multiple nodes start or end at the same position. A common example
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// for this are expressions and expression statement that always end at the same offset.
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//
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// Warning: Source markers are often emitted sorted by their source position but it's not guaranteed
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// and depends on the emitted `IR`.
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// They are only guaranteed to be sorted in increasing order by their destination position.
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for marker in self.sourcemap {
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// Take the closest start marker, but skip over start_markers that have the same start.
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if marker.source <= source_range.start()
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&& !start_marker.is_some_and(|existing| existing.source >= marker.source)
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{
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start_marker = Some(marker);
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}
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if marker.source >= source_range.end()
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&& !end_marker.is_some_and(|existing| existing.source <= marker.source)
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{
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end_marker = Some(marker);
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}
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}
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let (source_start, formatted_start) = start_marker
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.map(|marker| (marker.source, marker.dest))
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.unwrap_or_default();
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let (source_end, formatted_end) = end_marker
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.map_or((source.text_len(), self.code.text_len()), |marker| {
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(marker.source, marker.dest)
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});
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let source_range = TextRange::new(source_start, source_end);
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let formatted_range = TextRange::new(formatted_start, formatted_end);
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// Extend both ranges to include the indentation
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let source_range = extend_range_to_include_indent(source_range, source);
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let formatted_range = extend_range_to_include_indent(formatted_range, &self.code);
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PrintedRange {
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code: self.code[formatted_range].to_string(),
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source_range,
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}
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}
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}
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/// Extends `range` backwards (by reducing `range.start`) to include any directly preceding whitespace (`\t` or ` `).
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///
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/// # Panics
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/// If `range.start` is out of `source`'s bounds.
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fn extend_range_to_include_indent(range: TextRange, source: &str) -> TextRange {
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let whitespace_len: TextSize = source[..usize::from(range.start())]
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.chars()
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.rev()
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.take_while(|c| matches!(c, ' ' | '\t'))
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.map(TextLen::text_len)
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.sum();
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TextRange::new(range.start() - whitespace_len, range.end())
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}
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#[derive(Debug, Clone, Eq, PartialEq)]
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#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
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#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
|
|
pub struct PrintedRange {
|
|
code: String,
|
|
source_range: TextRange,
|
|
}
|
|
|
|
impl PrintedRange {
|
|
pub fn new(code: String, source_range: TextRange) -> Self {
|
|
Self { code, source_range }
|
|
}
|
|
|
|
pub fn empty() -> Self {
|
|
Self {
|
|
code: String::new(),
|
|
source_range: TextRange::default(),
|
|
}
|
|
}
|
|
|
|
/// The formatted code.
|
|
pub fn as_code(&self) -> &str {
|
|
&self.code
|
|
}
|
|
|
|
pub fn into_code(self) -> String {
|
|
self.code
|
|
}
|
|
|
|
/// The range the formatted code corresponds to in the source document.
|
|
pub fn source_range(&self) -> TextRange {
|
|
self.source_range
|
|
}
|
|
}
|
|
|
|
/// Public return type of the formatter
|
|
pub type FormatResult<F> = Result<F, FormatError>;
|
|
|
|
/// Formatting trait for types that can create a formatted representation. The `ruff_formatter` equivalent
|
|
/// to [`std::fmt::Display`].
|
|
///
|
|
/// ## Example
|
|
/// Implementing `Format` for a custom struct
|
|
///
|
|
/// ```
|
|
/// use ruff_formatter::{format, write, IndentStyle};
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_text_size::TextSize;
|
|
///
|
|
/// struct Paragraph(String);
|
|
///
|
|
/// impl Format<SimpleFormatContext> for Paragraph {
|
|
/// fn fmt(&self, f: &mut Formatter<SimpleFormatContext>) -> FormatResult<()> {
|
|
/// write!(f, [
|
|
/// text(&self.0),
|
|
/// hard_line_break(),
|
|
/// ])
|
|
/// }
|
|
/// }
|
|
///
|
|
/// # fn main() -> FormatResult<()> {
|
|
/// let paragraph = Paragraph(String::from("test"));
|
|
/// let formatted = format!(SimpleFormatContext::default(), [paragraph])?;
|
|
///
|
|
/// assert_eq!("test\n", formatted.print()?.as_code());
|
|
/// # Ok(())
|
|
/// # }
|
|
/// ```
|
|
pub trait Format<Context> {
|
|
/// Formats the object using the given formatter.
|
|
fn fmt(&self, f: &mut Formatter<Context>) -> FormatResult<()>;
|
|
}
|
|
|
|
impl<T, Context> Format<Context> for &T
|
|
where
|
|
T: ?Sized + Format<Context>,
|
|
{
|
|
#[inline]
|
|
fn fmt(&self, f: &mut Formatter<Context>) -> FormatResult<()> {
|
|
Format::fmt(&**self, f)
|
|
}
|
|
}
|
|
|
|
impl<T, Context> Format<Context> for &mut T
|
|
where
|
|
T: ?Sized + Format<Context>,
|
|
{
|
|
#[inline]
|
|
fn fmt(&self, f: &mut Formatter<Context>) -> FormatResult<()> {
|
|
Format::fmt(&**self, f)
|
|
}
|
|
}
|
|
|
|
impl<T, Context> Format<Context> for Option<T>
|
|
where
|
|
T: Format<Context>,
|
|
{
|
|
fn fmt(&self, f: &mut Formatter<Context>) -> FormatResult<()> {
|
|
match self {
|
|
Some(value) => value.fmt(f),
|
|
None => Ok(()),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<Context> Format<Context> for () {
|
|
#[inline]
|
|
fn fmt(&self, _: &mut Formatter<Context>) -> FormatResult<()> {
|
|
// Intentionally left empty
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
/// Rule that knows how to format an object of type `T`.
|
|
///
|
|
/// Implementing [Format] on the object itself is preferred over implementing [`FormatRule`] but
|
|
/// this isn't possible inside of a dependent crate for external type.
|
|
///
|
|
/// For example, the `ruff_js_formatter` crate isn't able to implement [Format] on `JsIfStatement`
|
|
/// because both the [Format] trait and `JsIfStatement` are external types (Rust's orphan rule).
|
|
///
|
|
/// That's why the `ruff_js_formatter` crate must define a new-type that implements the formatting
|
|
/// of `JsIfStatement`.
|
|
pub trait FormatRule<T, C> {
|
|
fn fmt(&self, item: &T, f: &mut Formatter<C>) -> FormatResult<()>;
|
|
}
|
|
|
|
/// Rule that supports customizing how it formats an object of type `T`.
|
|
pub trait FormatRuleWithOptions<T, C>: FormatRule<T, C> {
|
|
type Options;
|
|
|
|
/// Returns a new rule that uses the given options to format an object.
|
|
#[must_use]
|
|
fn with_options(self, options: Self::Options) -> Self;
|
|
}
|
|
|
|
/// Trait for an object that formats an object with a specified rule.
|
|
///
|
|
/// Gives access to the underlying item.
|
|
///
|
|
/// Useful in situation where a type itself doesn't implement [Format] (e.g. because of Rust's orphan rule)
|
|
/// but you want to implement some common formatting logic.
|
|
///
|
|
/// ## Examples
|
|
///
|
|
/// This can be useful if you want to format a `SyntaxNode` inside `ruff_formatter`.. `SyntaxNode` doesn't implement [Format]
|
|
/// itself but the language specific crate implements `AsFormat` and `IntoFormat` for it and the returned [Format]
|
|
/// implement [`FormatWithRule`].
|
|
///
|
|
/// ```ignore
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_formatter::{format, Formatted, FormatWithRule};
|
|
/// use ruff_rowan::{Language, SyntaxNode};
|
|
/// fn format_node<L: Language, F: FormatWithRule<SimpleFormatContext, Item=SyntaxNode<L>>>(node: F) -> FormatResult<Formatted<SimpleFormatContext>> {
|
|
/// let formatted = format!(SimpleFormatContext::default(), [node]);
|
|
/// let syntax = node.item();
|
|
/// // Do something with syntax
|
|
/// formatted;
|
|
/// }
|
|
/// ```
|
|
pub trait FormatWithRule<Context>: Format<Context> {
|
|
type Item;
|
|
|
|
/// Returns the associated item
|
|
fn item(&self) -> &Self::Item;
|
|
}
|
|
|
|
/// Formats the referenced `item` with the specified rule.
|
|
#[derive(Debug, Copy, Clone)]
|
|
pub struct FormatRefWithRule<'a, T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
item: &'a T,
|
|
rule: R,
|
|
context: PhantomData<C>,
|
|
}
|
|
|
|
impl<'a, T, R, C> FormatRefWithRule<'a, T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
pub fn new(item: &'a T, rule: R) -> Self {
|
|
Self {
|
|
item,
|
|
rule,
|
|
context: PhantomData,
|
|
}
|
|
}
|
|
|
|
pub fn rule(&self) -> &R {
|
|
&self.rule
|
|
}
|
|
}
|
|
|
|
impl<T, R, O, C> FormatRefWithRule<'_, T, R, C>
|
|
where
|
|
R: FormatRuleWithOptions<T, C, Options = O>,
|
|
{
|
|
#[must_use]
|
|
pub fn with_options(mut self, options: O) -> Self {
|
|
self.rule = self.rule.with_options(options);
|
|
self
|
|
}
|
|
}
|
|
|
|
impl<T, R, C> FormatWithRule<C> for FormatRefWithRule<'_, T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
type Item = T;
|
|
|
|
fn item(&self) -> &Self::Item {
|
|
self.item
|
|
}
|
|
}
|
|
|
|
impl<T, R, C> Format<C> for FormatRefWithRule<'_, T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
#[inline]
|
|
fn fmt(&self, f: &mut Formatter<C>) -> FormatResult<()> {
|
|
self.rule.fmt(self.item, f)
|
|
}
|
|
}
|
|
|
|
/// Formats the `item` with the specified rule.
|
|
#[derive(Debug, Clone)]
|
|
pub struct FormatOwnedWithRule<T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
item: T,
|
|
rule: R,
|
|
context: PhantomData<C>,
|
|
}
|
|
|
|
impl<T, R, C> FormatOwnedWithRule<T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
pub fn new(item: T, rule: R) -> Self {
|
|
Self {
|
|
item,
|
|
rule,
|
|
context: PhantomData,
|
|
}
|
|
}
|
|
|
|
#[must_use]
|
|
pub fn with_item(mut self, item: T) -> Self {
|
|
self.item = item;
|
|
self
|
|
}
|
|
}
|
|
|
|
impl<T, R, C> Format<C> for FormatOwnedWithRule<T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
#[inline]
|
|
fn fmt(&self, f: &mut Formatter<C>) -> FormatResult<()> {
|
|
self.rule.fmt(&self.item, f)
|
|
}
|
|
}
|
|
|
|
impl<T, R, O, C> FormatOwnedWithRule<T, R, C>
|
|
where
|
|
R: FormatRuleWithOptions<T, C, Options = O>,
|
|
{
|
|
#[must_use]
|
|
pub fn with_options(mut self, options: O) -> Self {
|
|
self.rule = self.rule.with_options(options);
|
|
self
|
|
}
|
|
}
|
|
|
|
impl<T, R, C> FormatWithRule<C> for FormatOwnedWithRule<T, R, C>
|
|
where
|
|
R: FormatRule<T, C>,
|
|
{
|
|
type Item = T;
|
|
|
|
fn item(&self) -> &Self::Item {
|
|
&self.item
|
|
}
|
|
}
|
|
|
|
/// The `write` function takes a target buffer and an `Arguments` struct that can be precompiled with the `format_args!` macro.
|
|
///
|
|
/// The arguments will be formatted in-order into the output buffer provided.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_formatter::{VecBuffer, format_args, FormatState, write, Formatted};
|
|
///
|
|
/// # fn main() -> FormatResult<()> {
|
|
/// let mut state = FormatState::new(SimpleFormatContext::default());
|
|
/// let mut buffer = VecBuffer::new(&mut state);
|
|
///
|
|
/// write!(&mut buffer, [format_args!(token("Hello World"))])?;
|
|
///
|
|
/// let formatted = Formatted::new(Document::from(buffer.into_vec()), SimpleFormatContext::default());
|
|
///
|
|
/// assert_eq!("Hello World", formatted.print()?.as_code());
|
|
/// # Ok(())
|
|
/// # }
|
|
/// ```
|
|
///
|
|
/// Please note that using [`write!`] might be preferable. Example:
|
|
///
|
|
/// ```
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_formatter::{VecBuffer, format_args, FormatState, write, Formatted};
|
|
///
|
|
/// # fn main() -> FormatResult<()> {
|
|
/// let mut state = FormatState::new(SimpleFormatContext::default());
|
|
/// let mut buffer = VecBuffer::new(&mut state);
|
|
///
|
|
/// write!(&mut buffer, [token("Hello World")])?;
|
|
///
|
|
/// let formatted = Formatted::new(Document::from(buffer.into_vec()), SimpleFormatContext::default());
|
|
///
|
|
/// assert_eq!("Hello World", formatted.print()?.as_code());
|
|
/// # Ok(())
|
|
/// # }
|
|
/// ```
|
|
#[inline]
|
|
pub fn write<Context>(
|
|
output: &mut dyn Buffer<Context = Context>,
|
|
args: Arguments<Context>,
|
|
) -> FormatResult<()> {
|
|
let mut f = Formatter::new(output);
|
|
|
|
f.write_fmt(args)
|
|
}
|
|
|
|
/// The `format` function takes an [`Arguments`] struct and returns the resulting formatting IR.
|
|
///
|
|
/// The [`Arguments`] instance can be created with the [`format_args!`].
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// Basic usage:
|
|
///
|
|
/// ```
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_formatter::{format, format_args};
|
|
///
|
|
/// # fn main() -> FormatResult<()> {
|
|
/// let formatted = format!(SimpleFormatContext::default(), [&format_args!(token("test"))])?;
|
|
/// assert_eq!("test", formatted.print()?.as_code());
|
|
/// # Ok(())
|
|
/// # }
|
|
/// ```
|
|
///
|
|
/// Please note that using [`format!`] might be preferable. Example:
|
|
///
|
|
/// ```
|
|
/// use ruff_formatter::prelude::*;
|
|
/// use ruff_formatter::{format};
|
|
///
|
|
/// # fn main() -> FormatResult<()> {
|
|
/// let formatted = format!(SimpleFormatContext::default(), [token("test")])?;
|
|
/// assert_eq!("test", formatted.print()?.as_code());
|
|
/// # Ok(())
|
|
/// # }
|
|
/// ```
|
|
pub fn format<Context>(
|
|
context: Context,
|
|
arguments: Arguments<Context>,
|
|
) -> FormatResult<Formatted<Context>>
|
|
where
|
|
Context: FormatContext,
|
|
{
|
|
let source_length = context.source_code().as_str().len();
|
|
// Use a simple heuristic to guess the number of expected format elements.
|
|
// See [#6612](https://github.com/astral-sh/ruff/pull/6612) for more details on how the formula was determined. Changes to our formatter, or supporting
|
|
// more languages may require fine tuning the formula.
|
|
let estimated_buffer_size = source_length / 2;
|
|
let mut state = FormatState::new(context);
|
|
let mut buffer = VecBuffer::with_capacity(estimated_buffer_size, &mut state);
|
|
|
|
buffer.write_fmt(arguments)?;
|
|
|
|
let mut document = Document::from(buffer.into_vec());
|
|
document.propagate_expand();
|
|
|
|
Ok(Formatted::new(document, state.into_context()))
|
|
}
|
|
|
|
/// This structure stores the state that is relevant for the formatting of the whole document.
|
|
///
|
|
/// This structure is different from [`crate::Formatter`] in that the formatting infrastructure
|
|
/// creates a new [`crate::Formatter`] for every [`crate::write`!] call, whereas this structure stays alive
|
|
/// for the whole process of formatting a root with [`crate::format`!].
|
|
pub struct FormatState<Context> {
|
|
context: Context,
|
|
|
|
group_id_builder: UniqueGroupIdBuilder,
|
|
}
|
|
|
|
#[allow(clippy::missing_fields_in_debug)]
|
|
impl<Context> std::fmt::Debug for FormatState<Context>
|
|
where
|
|
Context: std::fmt::Debug,
|
|
{
|
|
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
|
|
f.debug_struct("FormatState")
|
|
.field("context", &self.context)
|
|
.finish()
|
|
}
|
|
}
|
|
|
|
impl<Context> FormatState<Context> {
|
|
/// Creates a new state with the given language specific context
|
|
pub fn new(context: Context) -> Self {
|
|
Self {
|
|
context,
|
|
group_id_builder: UniqueGroupIdBuilder::default(),
|
|
}
|
|
}
|
|
|
|
pub fn into_context(self) -> Context {
|
|
self.context
|
|
}
|
|
|
|
/// Returns the context specifying how to format the current CST
|
|
pub fn context(&self) -> &Context {
|
|
&self.context
|
|
}
|
|
|
|
/// Returns a mutable reference to the context
|
|
pub fn context_mut(&mut self) -> &mut Context {
|
|
&mut self.context
|
|
}
|
|
|
|
/// Creates a new group id that is unique to this document. The passed debug name is used in the
|
|
/// [`std::fmt::Debug`] of the document if this is a debug build.
|
|
/// The name is unused for production builds and has no meaning on the equality of two group ids.
|
|
pub fn group_id(&self, debug_name: &'static str) -> GroupId {
|
|
self.group_id_builder.group_id(debug_name)
|
|
}
|
|
}
|