Improved Accessor Formatting

Added #[must_use] Attributes to DIsplay Wrappers Reduced Allocations in Indentation Formatting
Redfire75369 · Jan 16, 2024 · 403dd73 · 403dd73
1 parent 7572f0d
commit 403dd73
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Showing 18 changed files with 141 additions and 60 deletions.
diff --git a/ion/src/format/array.rs b/ion/src/format/array.rs
@@ -10,16 +10,17 @@ use std::fmt::{Display, Formatter, Write};
 use colored::Colorize;
 
 use crate::{Array, Context};
-use crate::format::{INDENT, NEWLINE};
+use crate::format::{indent_str, NEWLINE};
 use crate::format::Config;
 use crate::format::descriptor::format_descriptor;
 use crate::format::object::write_remaining;
 
-/// Formats an [JavaScript Array](Array) as a string using the given [configuration](Config).
+/// Formats an [JavaScript Array](Array) using the given [configuration](Config).
 pub fn format_array<'cx>(cx: &'cx Context, cfg: Config, array: &'cx Array<'cx>) -> ArrayDisplay<'cx> {
 	ArrayDisplay { cx, array, cfg }
 }
 
+#[must_use]
 pub struct ArrayDisplay<'cx> {
 	cx: &'cx Context,
 	array: &'cx Array<'cx>,
@@ -41,12 +42,12 @@ impl Display for ArrayDisplay<'_> {
 					f.write_str(NEWLINE)?;
 					let len = length.clamp(0, 100);
 
-					let inner = INDENT.repeat((self.cfg.indentation + self.cfg.depth + 1) as usize);
+					let inner = indent_str((self.cfg.indentation + self.cfg.depth + 1) as usize);
 
 					for index in 0..len {
-						f.write_str(&inner)?;
+						inner.fmt(f)?;
 						let desc = self.array.get_descriptor(self.cx, index).unwrap();
-						format_descriptor(self.cx, self.cfg, &desc).fmt(f)?;
+						format_descriptor(self.cx, self.cfg, &desc, Some(self.array.as_object())).fmt(f)?;
 						",".color(colour).fmt(f)?;
 						f.write_str(NEWLINE)?;
 					}
@@ -58,7 +59,7 @@ impl Display for ArrayDisplay<'_> {
 
 					for index in 0..len {
 						let desc = self.array.get_descriptor(self.cx, index).unwrap();
-						format_descriptor(self.cx, self.cfg, &desc).fmt(f)?;
+						format_descriptor(self.cx, self.cfg, &desc, Some(self.array.as_object())).fmt(f)?;
 
 						if index != len - 1 {
 							",".color(colour).fmt(f)?;
@@ -72,7 +73,7 @@ impl Display for ArrayDisplay<'_> {
 				write_remaining(f, remaining as usize, inner.as_deref(), colour)?;
 
 				if self.cfg.multiline {
-					f.write_str(&INDENT.repeat((self.cfg.indentation + self.cfg.depth) as usize))?;
+					indent_str((self.cfg.indentation + self.cfg.depth) as usize).fmt(f)?;
 				}
 
 				"]".color(colour).fmt(f)

diff --git a/ion/src/format/boxed.rs b/ion/src/format/boxed.rs
@@ -11,12 +11,13 @@ use crate::{Context, Object};
 use crate::format::Config;
 use crate::format::primitive::format_primitive;
 
-/// Formats a boxed primitive ([Object]) as a string using the given [configuration](Config).
+/// Formats a boxed primitive ([Object]) using the given [configuration](Config).
 /// The supported boxed types are `Boolean`, `Number`, `String` and `BigInt`.
 pub fn format_boxed<'cx>(cx: &'cx Context, cfg: Config, object: &'cx Object<'cx>) -> BoxedDisplay<'cx> {
 	BoxedDisplay { cx, object, cfg }
 }
 
+#[must_use]
 pub struct BoxedDisplay<'cx> {
 	cx: &'cx Context,
 	object: &'cx Object<'cx>,

diff --git a/ion/src/format/class.rs b/ion/src/format/class.rs
@@ -15,11 +15,12 @@ use crate::{Context, Object};
 use crate::format::Config;
 use crate::format::object::format_plain_object;
 
-/// Formats a [JavaScript Object](Object), along with the name of its constructor, as a string with the given [configuration](Config).
+/// Formats a [JavaScript Object](Object), along with the name of its constructor, with the given [configuration](Config).
 pub fn format_class_object<'cx>(cx: &'cx Context, cfg: Config, object: &'cx Object<'cx>) -> ClassObjectDisplay<'cx> {
 	ClassObjectDisplay { cx, object, cfg }
 }
 
+#[must_use]
 pub struct ClassObjectDisplay<'cx> {
 	cx: &'cx Context,
 	object: &'cx Object<'cx>,

diff --git a/ion/src/format/config.rs b/ion/src/format/config.rs
@@ -69,6 +69,7 @@ impl ColourConfig {
 
 /// Represents configuration for formatting
 #[derive(Clone, Copy, Debug)]
+#[must_use]
 pub struct Config {
 	pub colours: ColourConfig,
 	pub iteration: IteratorFlags,

diff --git a/ion/src/format/date.rs b/ion/src/format/date.rs
@@ -12,11 +12,12 @@ use colored::Colorize;
 use crate::{Context, Date};
 use crate::format::Config;
 
-/// Formats a [JavaScript Date](Date) as a string using the given [configuration](Config).
+/// Formats a [JavaScript Date](Date) using the given [configuration](Config).
 pub fn format_date<'cx>(cx: &'cx Context, cfg: Config, date: &'cx Date<'cx>) -> DateDisplay<'cx> {
 	DateDisplay { cx, date, cfg }
 }
 
+#[must_use]
 pub struct DateDisplay<'cx> {
 	cx: &'cx Context,
 	date: &'cx Date<'cx>,

diff --git a/ion/src/format/descriptor.rs b/ion/src/format/descriptor.rs
@@ -8,32 +8,76 @@ use std::fmt::{Display, Formatter};
 
 use colored::Colorize;
 
-use crate::{Context, PropertyDescriptor};
+use crate::{Context, Object, PropertyDescriptor};
 use crate::format::{Config, format_value};
+use crate::format::object::format_object;
+use crate::format::primitive::format_primitive;
 
 /// Formats a [descriptor](PropertyDescriptor) with the given [configuration](Config).
 pub fn format_descriptor<'cx>(
-	cx: &'cx Context, cfg: Config, desc: &'cx PropertyDescriptor<'cx>,
+	cx: &'cx Context, cfg: Config, desc: &'cx PropertyDescriptor<'cx>, object: Option<&'cx Object<'cx>>,
 ) -> DescriptorDisplay<'cx> {
-	DescriptorDisplay { cx, cfg, desc }
+	DescriptorDisplay { cx, cfg, desc, object }
 }
 
+#[must_use]
 pub struct DescriptorDisplay<'cx> {
 	cx: &'cx Context,
 	cfg: Config,
 	desc: &'cx PropertyDescriptor<'cx>,
+	object: Option<&'cx Object<'cx>>,
 }
 
 impl Display for DescriptorDisplay<'_> {
 	fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-		match (self.desc.getter(self.cx), self.desc.setter(self.cx)) {
-			(Some(_), Some(_)) => "[Getter/Setter]".color(self.cfg.colours.function).fmt(f),
-			(Some(_), None) => "[Getter]".color(self.cfg.colours.function).fmt(f),
-			(None, Some(_)) => "[Setter]".color(self.cfg.colours.function).fmt(f),
-			(None, None) => match self.desc.value(self.cx) {
+		let color = self.cfg.colours.function;
+
+		if let Some(getter) = self.desc.getter(self.cx) {
+			"[Getter".color(color).fmt(f)?;
+			if self.desc.setter(self.cx).is_some() {
+				"/Setter".color(color).fmt(f)?;
+			}
+			return if let Some(object) = self.object {
+				let value = match getter.call(self.cx, object, &[]) {
+					Ok(value) => value,
+					Err(report) => {
+						f.write_str("<inspection threw ")?;
+						match report {
+							Some(mut report) => {
+								report.stack = None;
+								report.format(self.cx).fmt(f)?;
+							}
+							None => f.write_str("unknown error")?,
+						}
+						f.write_str(">")?;
+						return "]".color(color).fmt(f);
+					}
+				};
+				if value.handle().is_object() {
+					"] ".color(color).fmt(f)?;
+					format_object(
+						self.cx,
+						self.cfg.depth(self.cfg.depth + 1).quoted(true),
+						value.to_object(self.cx),
+					)
+					.fmt(f)
+				} else {
+					": ".color(color).fmt(f)?;
+					format_primitive(self.cx, self.cfg.quoted(true), &value).fmt(f)?;
+					"]".color(color).fmt(f)
+				}
+			} else {
+				"]".color(color).fmt(f)
+			};
+		}
+
+		if self.desc.setter(self.cx).is_some() {
+			"[Setter]".color(color).fmt(f)
+		} else {
+			match self.desc.value(self.cx) {
 				Some(value) => format_value(self.cx, self.cfg.depth(self.cfg.depth + 1).quoted(true), &value).fmt(f),
-				None => unreachable!(),
-			},
+				None => f.write_str("<empty descriptor>"),
+			}
 		}
 	}
 }
diff --git a/ion/src/format/function.rs b/ion/src/format/function.rs
@@ -13,7 +13,7 @@ use indent::indent_by;
 use crate::{Context, Function};
 use crate::format::Config;
 
-/// Formats a [JavaScript Function](Function) as a string, using the given [configuration](Config).
+/// Formats a [function](Function), using the given [configuration](Config).
 ///
 /// ### Format
 /// ```js
@@ -25,6 +25,7 @@ pub fn format_function<'cx>(cx: &'cx Context, cfg: Config, function: &'cx Functi
 	FunctionDisplay { cx, function, cfg }
 }
 
+#[must_use]
 pub struct FunctionDisplay<'cx> {
 	cx: &'cx Context,
 	function: &'cx Function<'cx>,

diff --git a/ion/src/format/key.rs b/ion/src/format/key.rs
@@ -19,6 +19,7 @@ pub fn format_key<'cx>(cx: &'cx Context, cfg: Config, key: &'cx OwnedKey<'cx>) -
 	KeyDisplay { cx, cfg, key }
 }
 
+#[must_use]
 pub struct KeyDisplay<'cx> {
 	cx: &'cx Context,
 	cfg: Config,

diff --git a/ion/src/format/mod.rs b/ion/src/format/mod.rs
@@ -4,8 +4,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
+use std::borrow::Cow;
 use std::fmt;
 use std::fmt::{Display, Formatter};
+use std::str;
 
 pub use config::Config;
 
@@ -31,11 +33,27 @@ pub mod typedarray;
 pub const INDENT: &str = "  ";
 pub const NEWLINE: &str = "\n";
 
-/// Formats a [JavaScript Value](Value) as a string with the given [configuration](Config).
+#[must_use]
+pub fn indent_str(indentation: usize) -> Cow<'static, str> {
+	const MAX_INDENTS: usize = 128;
+	static INDENTS: &str = match str::from_utf8(&[b' '; MAX_INDENTS * 2]) {
+		Ok(indents) => indents,
+		_ => unreachable!(),
+	};
+
+	if indentation <= 128 {
+		Cow::Borrowed(&INDENTS[0..indentation * INDENT.len()])
+	} else {
+		Cow::Owned(INDENT.repeat(indentation))
+	}
+}
+
+/// Formats a [JavaScript Value](Value) with the given [configuration](Config).
 pub fn format_value<'cx>(cx: &'cx Context, cfg: Config, value: &'cx Value<'cx>) -> ValueDisplay<'cx> {
 	ValueDisplay { cx, value, cfg }
 }
 
+#[must_use]
 pub struct ValueDisplay<'cx> {
 	cx: &'cx Context,
 	value: &'cx Value<'cx>,

diff --git a/ion/src/format/object.rs b/ion/src/format/object.rs
@@ -14,7 +14,7 @@ use mozjs::jsapi::{ESClass, Type};
 
 use crate::{Array, Context, Date, Exception, Function, Object, Promise, PropertyDescriptor, PropertyKey, RegExp};
 use crate::conversions::ToValue;
-use crate::format::{INDENT, NEWLINE};
+use crate::format::{indent_str, NEWLINE};
 use crate::format::array::format_array;
 use crate::format::boxed::format_boxed;
 use crate::format::class::format_class_object;
@@ -31,12 +31,13 @@ use crate::typedarray::{
 	Uint16Array, Uint32Array, Uint8Array,
 };
 
-/// Formats a [JavaScript Object](Object), depending on its class, as a string using the given [configuration](Config).
+/// Formats a [JavaScript Object](Object), depending on its class, using the given [configuration](Config).
 /// The object is passed to more specific formatting functions, such as [format_array] and [format_date].
 pub fn format_object<'cx>(cx: &'cx Context, cfg: Config, object: Object<'cx>) -> ObjectDisplay<'cx> {
 	ObjectDisplay { cx, object, cfg }
 }
 
+#[must_use]
 pub struct ObjectDisplay<'cx> {
 	cx: &'cx Context,
 	object: Object<'cx>,
@@ -62,10 +63,10 @@ impl Display for ObjectDisplay<'_> {
 			ESC::Function => format_function(cx, cfg, &Function::from_object(cx, &self.object).unwrap()).fmt(f),
 			ESC::ArrayBuffer => format_array_buffer(cfg, &ArrayBuffer::from(object.into_local()).unwrap()).fmt(f),
 			ESC::Error => match Exception::from_object(cx, &self.object) {
-				Exception::Error(error) => f.write_str(&error.format()),
+				Exception::Error(error) => error.format().fmt(f),
 				_ => unreachable!("Expected Error"),
 			},
-			ESC::Object => format_plain_object(cx, cfg, &Object::from(object.into_local())).fmt(f),
+			ESC::Object => format_plain_object(cx, cfg, &self.object).fmt(f),
 			ESC::Other => {
 				if let Some(view) = ArrayBufferView::from(cx.root_object(object.handle().get())) {
 					'view: {
@@ -102,20 +103,18 @@ impl Display for ObjectDisplay<'_> {
 
 				format_class_object(cx, cfg, &self.object).fmt(f)
 			}
-			_ => {
-				let source = self.object.as_value(cx).to_source(cx).to_owned(cx);
-				f.write_str(&source)
-			}
+			_ => self.object.as_value(cx).to_source(cx).to_owned(cx).fmt(f),
 		}
 	}
 }
 
-/// Formats a [JavaScript Object](Object) as a string using the given [configuration](Config).
+/// Formats a [JavaScript Object](Object) using the given [configuration](Config).
 /// Disregards the class of the object.
 pub fn format_plain_object<'cx>(cx: &'cx Context, cfg: Config, object: &'cx Object<'cx>) -> PlainObjectDisplay<'cx> {
 	PlainObjectDisplay { cx, object, cfg }
 }
 
+#[must_use]
 pub struct PlainObjectDisplay<'cx> {
 	cx: &'cx Context,
 	object: &'cx Object<'cx>,
@@ -137,24 +136,24 @@ impl Display for PlainObjectDisplay<'_> {
 
 				if self.cfg.multiline {
 					f.write_str(NEWLINE)?;
-					let inner = INDENT.repeat((self.cfg.indentation + self.cfg.depth + 1) as usize);
+					let inner = indent_str((self.cfg.indentation + self.cfg.depth + 1) as usize);
 
 					for key in keys {
-						f.write_str(&inner)?;
+						inner.fmt(f)?;
 						let desc = self.object.get_descriptor(self.cx, &key).unwrap();
-						write_key_descriptor(f, self.cx, self.cfg, &key, &desc)?;
+						write_key_descriptor(f, self.cx, self.cfg, &key, &desc, self.object)?;
 						",".color(colour).fmt(f)?;
 						f.write_str(NEWLINE)?;
 					}
 
-					f.write_str(&INDENT.repeat((self.cfg.indentation + self.cfg.depth) as usize))?;
+					indent_str((self.cfg.indentation + self.cfg.depth) as usize).fmt(f)?;
 				} else {
 					f.write_char(' ')?;
 					let len = length.clamp(0, 3);
 
 					for (i, key) in keys.enumerate() {
 						let desc = self.object.get_descriptor(self.cx, &key).unwrap();
-						write_key_descriptor(f, self.cx, self.cfg, &key, &desc)?;
+						write_key_descriptor(f, self.cx, self.cfg, &key, &desc, self.object)?;
 
 						if i != len - 1 {
 							",".color(colour).fmt(f)?;
@@ -175,11 +174,11 @@ impl Display for PlainObjectDisplay<'_> {
 }
 
 fn write_key_descriptor(
-	f: &mut Formatter, cx: &Context, cfg: Config, key: &PropertyKey, desc: &PropertyDescriptor,
+	f: &mut Formatter, cx: &Context, cfg: Config, key: &PropertyKey, desc: &PropertyDescriptor, object: &Object,
 ) -> fmt::Result {
 	format_key(cx, cfg, &key.to_owned_key(cx)).fmt(f)?;
 	": ".color(cfg.colours.object).fmt(f)?;
-	format_descriptor(cx, cfg, desc).fmt(f)
+	format_descriptor(cx, cfg, desc, Some(object)).fmt(f)
 }
 
 pub(crate) fn write_remaining(f: &mut Formatter, remaining: usize, inner: Option<&str>, colour: Color) -> fmt::Result {

diff --git a/ion/src/format/primitive.rs b/ion/src/format/primitive.rs
@@ -16,12 +16,13 @@ use crate::conversions::FromValue;
 use crate::format::Config;
 use crate::format::symbol::format_symbol;
 
-/// Formats a primitive value as a string using the given [configuration](Config).
+/// Formats a primitive value using the given [configuration](Config).
 /// The supported types are `boolean`, `number`, `string`, `symbol`, `null` and `undefined`.
 pub fn format_primitive<'cx>(cx: &'cx Context, cfg: Config, value: &'cx Value<'cx>) -> PrimitiveDisplay<'cx> {
 	PrimitiveDisplay { cx, value, cfg }
 }
 
+#[must_use]
 pub struct PrimitiveDisplay<'cx> {
 	cx: &'cx Context,
 	value: &'cx Value<'cx>,
@@ -54,7 +55,7 @@ impl Display for PrimitiveDisplay<'_> {
 			if self.cfg.quoted {
 				write!(f, "{0}{1}{0}", r#"""#.color(colours.string), str.color(colours.string))
 			} else {
-				f.write_str(&str)
+				str.fmt(f)
 			}
 		} else if value.is_null() {
 			"null".color(colours.null).fmt(f)