git.delta.rocks / jrsonnet / refs/commits / 4fe0b2f8cad3

difftreelog

fix spacing in array toString

Yaroslav Bolyukin2024-06-18parent: #78734bc.patch.diff
in: master

1 file changed

modifiedcrates/jrsonnet-evaluator/src/manifest.rsdiffbeforeafterboth
before · crates/jrsonnet-evaluator/src/manifest.rs
1use std::{borrow::Cow, fmt::Write, ptr};23use crate::{bail, Result, ResultExt, State, Val};45pub trait ManifestFormat {6	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()>;7	fn manifest(&self, val: Val) -> Result<String> {8		let mut out = String::new();9		self.manifest_buf(val, &mut out)?;10		Ok(out)11	}12	/// When outputing to file, is it safe to append a trailing newline (I.e newline won't change13	/// the meaning).14	///15	/// Default implementation returns `true`16	fn file_trailing_newline(&self) -> bool {17		true18	}19}20impl<T> ManifestFormat for Box<T>21where22	T: ManifestFormat + ?Sized,23{24	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {25		let inner = &**self;26		inner.manifest_buf(val, buf)27	}28	fn file_trailing_newline(&self) -> bool {29		let inner = &**self;30		inner.file_trailing_newline()31	}32}33impl<T> ManifestFormat for &'_ T34where35	T: ManifestFormat + ?Sized,36{37	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {38		let inner = &**self;39		inner.manifest_buf(val, buf)40	}41	fn file_trailing_newline(&self) -> bool {42		let inner = &**self;43		inner.file_trailing_newline()44	}45}4647#[derive(PartialEq, Eq, Clone, Copy)]48enum JsonFormatting {49	// Applied in manifestification50	Manifest,51	/// Used for std.manifestJson52	/// Empty array/objects extends to "[\n\n]" instead of "[ ]" as in manifest53	Std,54	/// No line breaks, used in `obj+''`55	ToString,56	/// Minified json57	Minify,58}5960pub struct JsonFormat<'s> {61	padding: Cow<'s, str>,62	mtype: JsonFormatting,63	newline: &'s str,64	key_val_sep: &'s str,65	#[cfg(feature = "exp-preserve-order")]66	preserve_order: bool,67	#[cfg(feature = "exp-bigint")]68	preserve_bigints: bool,69	debug_truncate_strings: Option<usize>,70}7172impl<'s> JsonFormat<'s> {73	// Minifying format74	pub fn minify(#[cfg(feature = "exp-preserve-order")] preserve_order: bool) -> Self {75		Self {76			padding: Cow::Borrowed(""),77			mtype: JsonFormatting::Minify,78			newline: "\n",79			key_val_sep: ":",80			#[cfg(feature = "exp-preserve-order")]81			preserve_order,82			#[cfg(feature = "exp-bigint")]83			preserve_bigints: false,84			debug_truncate_strings: None,85		}86	}87	// Same format as std.toString88	pub fn std_to_string() -> Self {89		Self {90			padding: Cow::Borrowed(""),91			mtype: JsonFormatting::ToString,92			newline: "\n",93			key_val_sep: ": ",94			#[cfg(feature = "exp-preserve-order")]95			preserve_order: false,96			#[cfg(feature = "exp-bigint")]97			preserve_bigints: false,98			debug_truncate_strings: None,99		}100	}101	pub fn std_to_json(102		padding: String,103		newline: &'s str,104		key_val_sep: &'s str,105		#[cfg(feature = "exp-preserve-order")] preserve_order: bool,106	) -> Self {107		Self {108			padding: Cow::Owned(padding),109			mtype: JsonFormatting::Std,110			newline,111			key_val_sep,112			#[cfg(feature = "exp-preserve-order")]113			preserve_order,114			#[cfg(feature = "exp-bigint")]115			preserve_bigints: false,116			debug_truncate_strings: None,117		}118	}119	// Same format as CLI manifestification120	pub fn cli(121		padding: usize,122		#[cfg(feature = "exp-preserve-order")] preserve_order: bool,123	) -> Self {124		if padding == 0 {125			return Self::minify(126				#[cfg(feature = "exp-preserve-order")]127				preserve_order,128			);129		}130		Self {131			padding: Cow::Owned(" ".repeat(padding)),132			mtype: JsonFormatting::Manifest,133			newline: "\n",134			key_val_sep: ": ",135			#[cfg(feature = "exp-preserve-order")]136			preserve_order,137			#[cfg(feature = "exp-bigint")]138			preserve_bigints: false,139			debug_truncate_strings: None,140		}141	}142	// Same format as CLI manifestification143	pub fn debug() -> Self {144		Self {145			padding: Cow::Borrowed("   "),146			mtype: JsonFormatting::Manifest,147			newline: "\n",148			key_val_sep: ": ",149			#[cfg(feature = "exp-preserve-order")]150			preserve_order: true,151			#[cfg(feature = "exp-bigint")]152			preserve_bigints: true,153			debug_truncate_strings: Some(256),154		}155	}156}157impl Default for JsonFormat<'static> {158	fn default() -> Self {159		Self {160			padding: Cow::Borrowed("    "),161			mtype: JsonFormatting::Manifest,162			newline: "\n",163			key_val_sep: ": ",164			#[cfg(feature = "exp-preserve-order")]165			preserve_order: false,166			#[cfg(feature = "exp-bigint")]167			preserve_bigints: false,168			debug_truncate_strings: None,169		}170	}171}172173pub fn manifest_json_ex(val: &Val, options: &JsonFormat<'_>) -> Result<String> {174	let mut out = String::new();175	manifest_json_ex_buf(val, &mut out, &mut String::new(), options)?;176	Ok(out)177}178179#[allow(clippy::too_many_lines)]180fn manifest_json_ex_buf(181	val: &Val,182	buf: &mut String,183	cur_padding: &mut String,184	options: &JsonFormat<'_>,185) -> Result<()> {186	use JsonFormatting::*;187188	let mtype = options.mtype;189	match val {190		Val::Bool(v) => {191			if *v {192				buf.push_str("true");193			} else {194				buf.push_str("false");195			}196		}197		Val::Null => buf.push_str("null"),198		Val::Str(s) => {199			let flat = s.clone().into_flat();200			if let Some(truncate) = options.debug_truncate_strings {201				if flat.len() > truncate {202					let (start, end) = flat.split_at(truncate / 2);203					let (_, end) = end.split_at(end.len() - truncate / 2);204					escape_string_json_buf(&format!("{start}..{end}"), buf);205				} else {206					escape_string_json_buf(&flat, buf);207				}208			} else {209				escape_string_json_buf(&flat, buf);210			}211		}212		Val::Num(n) => write!(buf, "{n}").unwrap(),213		#[cfg(feature = "exp-bigint")]214		Val::BigInt(n) => {215			if options.preserve_bigints {216				write!(buf, "{n}").unwrap();217			} else {218				write!(buf, "{:?}", n.to_string()).unwrap();219			}220		}221		Val::Arr(items) => {222			buf.push('[');223224			let old_len = cur_padding.len();225			cur_padding.push_str(&options.padding);226227			let mut had_items = false;228			for (i, item) in items.iter().enumerate() {229				had_items = true;230				let item = item.with_description(|| format!("elem <{i}> evaluation"))?;231232				if i != 0 {233					buf.push(',');234				}235				match mtype {236					Manifest | Std => {237						buf.push_str(options.newline);238						buf.push_str(cur_padding);239					}240					ToString => buf.push(' '),241					Minify => {}242				};243244				State::push_description(245					|| format!("elem <{i}> manifestification"),246					|| manifest_json_ex_buf(&item, buf, cur_padding, options),247				)?;248			}249250			cur_padding.truncate(old_len);251252			match mtype {253				Manifest | ToString if !had_items => {254					// Empty array as "[ ]"255					buf.push(' ');256				}257				Manifest => {258					buf.push_str(options.newline);259					buf.push_str(cur_padding);260				}261				Std => {262					if !had_items {263						// Stdlib formats empty array as "[\n\n]"264						buf.push_str(options.newline);265					}266					buf.push_str(options.newline);267					buf.push_str(cur_padding);268				}269				Minify | ToString => {}270			}271272			buf.push(']');273		}274		Val::Obj(obj) => {275			obj.run_assertions()?;276			buf.push('{');277278			let old_len = cur_padding.len();279			cur_padding.push_str(&options.padding);280281			let mut had_fields = false;282			for (i, (key, value)) in obj283				.iter(284					#[cfg(feature = "exp-preserve-order")]285					options.preserve_order,286				)287				.enumerate()288			{289				had_fields = true;290				let value = value.with_description(|| format!("field <{key}> evaluation"))?;291292				if i != 0 {293					buf.push(',');294				}295				match mtype {296					Manifest | Std => {297						buf.push_str(options.newline);298						buf.push_str(cur_padding);299					}300					ToString if i != 0 => buf.push(' '),301					Minify | ToString => {}302				}303304				escape_string_json_buf(&key, buf);305				buf.push_str(options.key_val_sep);306				State::push_description(307					|| format!("field <{key}> manifestification"),308					|| manifest_json_ex_buf(&value, buf, cur_padding, options),309				)?;310			}311312			cur_padding.truncate(old_len);313314			match mtype {315				Manifest | ToString if !had_fields => {316					// Empty object as "{ }"317					buf.push(' ');318				}319				Manifest => {320					buf.push_str(options.newline);321					buf.push_str(cur_padding);322				}323				Std => {324					if !had_fields {325						// Stdlib formats empty object as "{\n\n}"326						buf.push_str(options.newline);327					}328					buf.push_str(options.newline);329					buf.push_str(cur_padding);330				}331				Minify | ToString => {}332			}333334			buf.push('}');335		}336		Val::Func(_) => bail!("tried to manifest function"),337	};338	Ok(())339}340341impl ManifestFormat for JsonFormat<'_> {342	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {343		manifest_json_ex_buf(&val, buf, &mut String::new(), self)344	}345}346347pub struct ToStringFormat;348impl ManifestFormat for ToStringFormat {349	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {350		JsonFormat::std_to_string().manifest_buf(val, out)351	}352	fn file_trailing_newline(&self) -> bool {353		false354	}355}356pub struct StringFormat;357impl ManifestFormat for StringFormat {358	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {359		let Val::Str(s) = val else {360			bail!(361				"output should be string for string manifest format, got {}",362				val.value_type()363			)364		};365		write!(out, "{s}").unwrap();366		Ok(())367	}368	fn file_trailing_newline(&self) -> bool {369		false370	}371}372373pub struct YamlStreamFormat<I> {374	inner: I,375	c_document_end: bool,376	end_newline: bool,377}378impl<I> YamlStreamFormat<I> {379	pub fn std_yaml_stream(inner: I, c_document_end: bool) -> Self {380		Self {381			inner,382			c_document_end,383			// Stdlib format always inserts useless newline at the end384			end_newline: true,385		}386	}387	pub fn cli(inner: I) -> Self {388		Self {389			inner,390			c_document_end: true,391			end_newline: false,392		}393	}394}395impl<I: ManifestFormat> ManifestFormat for YamlStreamFormat<I> {396	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {397		let Val::Arr(arr) = val else {398			bail!(399				"output should be array for yaml stream format, got {}",400				val.value_type()401			)402		};403		if !arr.is_empty() {404			for (i, v) in arr.iter().enumerate() {405				let v = v.with_description(|| format!("elem <{i}> evaluation"))?;406				out.push_str("---\n");407				State::push_description(408					|| format!("elem <{i}> manifestification"),409					|| self.inner.manifest_buf(v, out),410				)?;411				out.push('\n');412			}413		}414		if self.c_document_end {415			out.push_str("...");416		}417		if self.end_newline {418			out.push('\n');419		}420		Ok(())421	}422}423424pub fn escape_string_json(s: &str) -> String {425	let mut buf = String::new();426	escape_string_json_buf(s, &mut buf);427	buf428}429430// Json string encoding was borrowed from https://github.com/serde-rs/json431432const BB: u8 = b'b'; // \x08433const TT: u8 = b't'; // \x09434const NN: u8 = b'n'; // \x0A435const FF: u8 = b'f'; // \x0C436const RR: u8 = b'r'; // \x0D437const QU: u8 = b'"'; // \x22438const BS: u8 = b'\\'; // \x5C439const UU: u8 = b'u'; // \x00...\x1F except the ones above440const __: u8 = 0;441442// Lookup table of escape sequences. A value of b'x' at index i means that byte443// i is escaped as "\x" in JSON. A value of 0 means that byte i is not escaped.444static ESCAPE: [u8; 256] = [445	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F446	UU, UU, UU, UU, UU, UU, UU, UU, BB, TT, NN, UU, FF, RR, UU, UU, // 0447	UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, // 1448	__, __, QU, __, __, __, __, __, __, __, __, __, __, __, __, __, // 2449	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 3450	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 4451	__, __, __, __, __, __, __, __, __, __, __, __, BS, __, __, __, // 5452	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 6453	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 7454	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 8455	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 9456	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // A457	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // B458	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // C459	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // D460	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // E461	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // F462];463464pub fn escape_string_json_buf(value: &str, buf: &mut String) {465	// Safety: we only write correct utf-8 in this function466	let buf: &mut Vec<u8> = unsafe { &mut *ptr::from_mut(buf).cast::<Vec<u8>>() };467	let bytes = value.as_bytes();468469	// Perfect for ascii strings, removes any reallocations470	buf.reserve(value.len() + 2);471472	buf.push(b'"');473474	let mut start = 0;475476	for (i, &byte) in bytes.iter().enumerate() {477		let escape = ESCAPE[byte as usize];478		if escape == __ {479			continue;480		}481482		if start < i {483			buf.extend_from_slice(&bytes[start..i]);484		}485		start = i + 1;486487		match escape {488			self::BB | self::TT | self::NN | self::FF | self::RR | self::QU | self::BS => {489				buf.extend_from_slice(&[b'\\', escape]);490			}491			self::UU => {492				static HEX_DIGITS: [u8; 16] = *b"0123456789abcdef";493				let bytes = &[494					b'\\',495					b'u',496					b'0',497					b'0',498					HEX_DIGITS[(byte >> 4) as usize],499					HEX_DIGITS[(byte & 0xF) as usize],500				];501				buf.extend_from_slice(bytes);502			}503			_ => unreachable!(),504		}505	}506507	if start == bytes.len() {508		buf.push(b'"');509		return;510	}511512	buf.extend_from_slice(&bytes[start..]);513	buf.push(b'"');514}
after · crates/jrsonnet-evaluator/src/manifest.rs
1use std::{borrow::Cow, fmt::Write, ptr};23use crate::{bail, Result, ResultExt, State, Val};45pub trait ManifestFormat {6	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()>;7	fn manifest(&self, val: Val) -> Result<String> {8		let mut out = String::new();9		self.manifest_buf(val, &mut out)?;10		Ok(out)11	}12	/// When outputing to file, is it safe to append a trailing newline (I.e newline won't change13	/// the meaning).14	///15	/// Default implementation returns `true`16	fn file_trailing_newline(&self) -> bool {17		true18	}19}20impl<T> ManifestFormat for Box<T>21where22	T: ManifestFormat + ?Sized,23{24	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {25		let inner = &**self;26		inner.manifest_buf(val, buf)27	}28	fn file_trailing_newline(&self) -> bool {29		let inner = &**self;30		inner.file_trailing_newline()31	}32}33impl<T> ManifestFormat for &'_ T34where35	T: ManifestFormat + ?Sized,36{37	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {38		let inner = &**self;39		inner.manifest_buf(val, buf)40	}41	fn file_trailing_newline(&self) -> bool {42		let inner = &**self;43		inner.file_trailing_newline()44	}45}4647#[derive(PartialEq, Eq, Clone, Copy)]48enum JsonFormatting {49	// Applied in manifestification50	Manifest,51	/// Used for std.manifestJson52	/// Empty array/objects extends to "[\n\n]" instead of "[ ]" as in manifest53	Std,54	/// No line breaks, used in `obj+''`55	ToString,56	/// Minified json57	Minify,58}5960pub struct JsonFormat<'s> {61	padding: Cow<'s, str>,62	mtype: JsonFormatting,63	newline: &'s str,64	key_val_sep: &'s str,65	#[cfg(feature = "exp-preserve-order")]66	preserve_order: bool,67	#[cfg(feature = "exp-bigint")]68	preserve_bigints: bool,69	debug_truncate_strings: Option<usize>,70}7172impl<'s> JsonFormat<'s> {73	// Minifying format74	pub fn minify(#[cfg(feature = "exp-preserve-order")] preserve_order: bool) -> Self {75		Self {76			padding: Cow::Borrowed(""),77			mtype: JsonFormatting::Minify,78			newline: "\n",79			key_val_sep: ":",80			#[cfg(feature = "exp-preserve-order")]81			preserve_order,82			#[cfg(feature = "exp-bigint")]83			preserve_bigints: false,84			debug_truncate_strings: None,85		}86	}87	// Same format as std.toString88	pub fn std_to_string() -> Self {89		Self {90			padding: Cow::Borrowed(""),91			mtype: JsonFormatting::ToString,92			newline: "\n",93			key_val_sep: ": ",94			#[cfg(feature = "exp-preserve-order")]95			preserve_order: false,96			#[cfg(feature = "exp-bigint")]97			preserve_bigints: false,98			debug_truncate_strings: None,99		}100	}101	pub fn std_to_json(102		padding: String,103		newline: &'s str,104		key_val_sep: &'s str,105		#[cfg(feature = "exp-preserve-order")] preserve_order: bool,106	) -> Self {107		Self {108			padding: Cow::Owned(padding),109			mtype: JsonFormatting::Std,110			newline,111			key_val_sep,112			#[cfg(feature = "exp-preserve-order")]113			preserve_order,114			#[cfg(feature = "exp-bigint")]115			preserve_bigints: false,116			debug_truncate_strings: None,117		}118	}119	// Same format as CLI manifestification120	pub fn cli(121		padding: usize,122		#[cfg(feature = "exp-preserve-order")] preserve_order: bool,123	) -> Self {124		if padding == 0 {125			return Self::minify(126				#[cfg(feature = "exp-preserve-order")]127				preserve_order,128			);129		}130		Self {131			padding: Cow::Owned(" ".repeat(padding)),132			mtype: JsonFormatting::Manifest,133			newline: "\n",134			key_val_sep: ": ",135			#[cfg(feature = "exp-preserve-order")]136			preserve_order,137			#[cfg(feature = "exp-bigint")]138			preserve_bigints: false,139			debug_truncate_strings: None,140		}141	}142	// Same format as CLI manifestification143	pub fn debug() -> Self {144		Self {145			padding: Cow::Borrowed("   "),146			mtype: JsonFormatting::Manifest,147			newline: "\n",148			key_val_sep: ": ",149			#[cfg(feature = "exp-preserve-order")]150			preserve_order: true,151			#[cfg(feature = "exp-bigint")]152			preserve_bigints: true,153			debug_truncate_strings: Some(256),154		}155	}156}157impl Default for JsonFormat<'static> {158	fn default() -> Self {159		Self {160			padding: Cow::Borrowed("    "),161			mtype: JsonFormatting::Manifest,162			newline: "\n",163			key_val_sep: ": ",164			#[cfg(feature = "exp-preserve-order")]165			preserve_order: false,166			#[cfg(feature = "exp-bigint")]167			preserve_bigints: false,168			debug_truncate_strings: None,169		}170	}171}172173pub fn manifest_json_ex(val: &Val, options: &JsonFormat<'_>) -> Result<String> {174	let mut out = String::new();175	manifest_json_ex_buf(val, &mut out, &mut String::new(), options)?;176	Ok(out)177}178179#[allow(clippy::too_many_lines)]180fn manifest_json_ex_buf(181	val: &Val,182	buf: &mut String,183	cur_padding: &mut String,184	options: &JsonFormat<'_>,185) -> Result<()> {186	use JsonFormatting::*;187188	let mtype = options.mtype;189	match val {190		Val::Bool(v) => {191			if *v {192				buf.push_str("true");193			} else {194				buf.push_str("false");195			}196		}197		Val::Null => buf.push_str("null"),198		Val::Str(s) => {199			let flat = s.clone().into_flat();200			if let Some(truncate) = options.debug_truncate_strings {201				if flat.len() > truncate {202					let (start, end) = flat.split_at(truncate / 2);203					let (_, end) = end.split_at(end.len() - truncate / 2);204					escape_string_json_buf(&format!("{start}..{end}"), buf);205				} else {206					escape_string_json_buf(&flat, buf);207				}208			} else {209				escape_string_json_buf(&flat, buf);210			}211		}212		Val::Num(n) => write!(buf, "{n}").unwrap(),213		#[cfg(feature = "exp-bigint")]214		Val::BigInt(n) => {215			if options.preserve_bigints {216				write!(buf, "{n}").unwrap();217			} else {218				write!(buf, "{:?}", n.to_string()).unwrap();219			}220		}221		Val::Arr(items) => {222			buf.push('[');223224			let old_len = cur_padding.len();225			cur_padding.push_str(&options.padding);226227			let mut had_items = false;228			for (i, item) in items.iter().enumerate() {229				had_items = true;230				let item = item.with_description(|| format!("elem <{i}> evaluation"))?;231232				if i != 0 {233					buf.push(',');234				}235				match mtype {236					Manifest | Std => {237						buf.push_str(options.newline);238						buf.push_str(cur_padding);239					}240					ToString if i != 0 => buf.push(' '),241					Minify | ToString => {}242				};243244				State::push_description(245					|| format!("elem <{i}> manifestification"),246					|| manifest_json_ex_buf(&item, buf, cur_padding, options),247				)?;248			}249250			cur_padding.truncate(old_len);251252			match mtype {253				Manifest | ToString if !had_items => {254					// Empty array as "[ ]"255					buf.push(' ');256				}257				Manifest => {258					buf.push_str(options.newline);259					buf.push_str(cur_padding);260				}261				Std => {262					if !had_items {263						// Stdlib formats empty array as "[\n\n]"264						buf.push_str(options.newline);265					}266					buf.push_str(options.newline);267					buf.push_str(cur_padding);268				}269				Minify | ToString => {}270			}271272			buf.push(']');273		}274		Val::Obj(obj) => {275			obj.run_assertions()?;276			buf.push('{');277278			let old_len = cur_padding.len();279			cur_padding.push_str(&options.padding);280281			let mut had_fields = false;282			for (i, (key, value)) in obj283				.iter(284					#[cfg(feature = "exp-preserve-order")]285					options.preserve_order,286				)287				.enumerate()288			{289				had_fields = true;290				let value = value.with_description(|| format!("field <{key}> evaluation"))?;291292				if i != 0 {293					buf.push(',');294				}295				match mtype {296					Manifest | Std => {297						buf.push_str(options.newline);298						buf.push_str(cur_padding);299					}300					ToString if i != 0 => buf.push(' '),301					Minify | ToString => {}302				}303304				escape_string_json_buf(&key, buf);305				buf.push_str(options.key_val_sep);306				State::push_description(307					|| format!("field <{key}> manifestification"),308					|| manifest_json_ex_buf(&value, buf, cur_padding, options),309				)?;310			}311312			cur_padding.truncate(old_len);313314			match mtype {315				Manifest | ToString if !had_fields => {316					// Empty object as "{ }"317					buf.push(' ');318				}319				Manifest => {320					buf.push_str(options.newline);321					buf.push_str(cur_padding);322				}323				Std => {324					if !had_fields {325						// Stdlib formats empty object as "{\n\n}"326						buf.push_str(options.newline);327					}328					buf.push_str(options.newline);329					buf.push_str(cur_padding);330				}331				Minify | ToString => {}332			}333334			buf.push('}');335		}336		Val::Func(_) => bail!("tried to manifest function"),337	};338	Ok(())339}340341impl ManifestFormat for JsonFormat<'_> {342	fn manifest_buf(&self, val: Val, buf: &mut String) -> Result<()> {343		manifest_json_ex_buf(&val, buf, &mut String::new(), self)344	}345}346347pub struct ToStringFormat;348impl ManifestFormat for ToStringFormat {349	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {350		JsonFormat::std_to_string().manifest_buf(val, out)351	}352	fn file_trailing_newline(&self) -> bool {353		false354	}355}356pub struct StringFormat;357impl ManifestFormat for StringFormat {358	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {359		let Val::Str(s) = val else {360			bail!(361				"output should be string for string manifest format, got {}",362				val.value_type()363			)364		};365		write!(out, "{s}").unwrap();366		Ok(())367	}368	fn file_trailing_newline(&self) -> bool {369		false370	}371}372373pub struct YamlStreamFormat<I> {374	inner: I,375	c_document_end: bool,376	end_newline: bool,377}378impl<I> YamlStreamFormat<I> {379	pub fn std_yaml_stream(inner: I, c_document_end: bool) -> Self {380		Self {381			inner,382			c_document_end,383			// Stdlib format always inserts useless newline at the end384			end_newline: true,385		}386	}387	pub fn cli(inner: I) -> Self {388		Self {389			inner,390			c_document_end: true,391			end_newline: false,392		}393	}394}395impl<I: ManifestFormat> ManifestFormat for YamlStreamFormat<I> {396	fn manifest_buf(&self, val: Val, out: &mut String) -> Result<()> {397		let Val::Arr(arr) = val else {398			bail!(399				"output should be array for yaml stream format, got {}",400				val.value_type()401			)402		};403		if !arr.is_empty() {404			for (i, v) in arr.iter().enumerate() {405				let v = v.with_description(|| format!("elem <{i}> evaluation"))?;406				out.push_str("---\n");407				State::push_description(408					|| format!("elem <{i}> manifestification"),409					|| self.inner.manifest_buf(v, out),410				)?;411				out.push('\n');412			}413		}414		if self.c_document_end {415			out.push_str("...");416		}417		if self.end_newline {418			out.push('\n');419		}420		Ok(())421	}422}423424pub fn escape_string_json(s: &str) -> String {425	let mut buf = String::new();426	escape_string_json_buf(s, &mut buf);427	buf428}429430// Json string encoding was borrowed from https://github.com/serde-rs/json431432const BB: u8 = b'b'; // \x08433const TT: u8 = b't'; // \x09434const NN: u8 = b'n'; // \x0A435const FF: u8 = b'f'; // \x0C436const RR: u8 = b'r'; // \x0D437const QU: u8 = b'"'; // \x22438const BS: u8 = b'\\'; // \x5C439const UU: u8 = b'u'; // \x00...\x1F except the ones above440const __: u8 = 0;441442// Lookup table of escape sequences. A value of b'x' at index i means that byte443// i is escaped as "\x" in JSON. A value of 0 means that byte i is not escaped.444static ESCAPE: [u8; 256] = [445	//   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F446	UU, UU, UU, UU, UU, UU, UU, UU, BB, TT, NN, UU, FF, RR, UU, UU, // 0447	UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, // 1448	__, __, QU, __, __, __, __, __, __, __, __, __, __, __, __, __, // 2449	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 3450	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 4451	__, __, __, __, __, __, __, __, __, __, __, __, BS, __, __, __, // 5452	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 6453	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 7454	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 8455	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 9456	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // A457	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // B458	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // C459	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // D460	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // E461	__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // F462];463464pub fn escape_string_json_buf(value: &str, buf: &mut String) {465	// Safety: we only write correct utf-8 in this function466	let buf: &mut Vec<u8> = unsafe { &mut *ptr::from_mut(buf).cast::<Vec<u8>>() };467	let bytes = value.as_bytes();468469	// Perfect for ascii strings, removes any reallocations470	buf.reserve(value.len() + 2);471472	buf.push(b'"');473474	let mut start = 0;475476	for (i, &byte) in bytes.iter().enumerate() {477		let escape = ESCAPE[byte as usize];478		if escape == __ {479			continue;480		}481482		if start < i {483			buf.extend_from_slice(&bytes[start..i]);484		}485		start = i + 1;486487		match escape {488			self::BB | self::TT | self::NN | self::FF | self::RR | self::QU | self::BS => {489				buf.extend_from_slice(&[b'\\', escape]);490			}491			self::UU => {492				static HEX_DIGITS: [u8; 16] = *b"0123456789abcdef";493				let bytes = &[494					b'\\',495					b'u',496					b'0',497					b'0',498					HEX_DIGITS[(byte >> 4) as usize],499					HEX_DIGITS[(byte & 0xF) as usize],500				];501				buf.extend_from_slice(bytes);502			}503			_ => unreachable!(),504		}505	}506507	if start == bytes.len() {508		buf.push(b'"');509		return;510	}511512	buf.extend_from_slice(&bytes[start..]);513	buf.push(b'"');514}