grass/src/builtin/string.rs
ConnorSkees 9a6c8ce019 add string interning
this seems to improve performance by ~20% as well as significantly
decrease memory usage
2020-05-21 22:46:40 -04:00

380 lines
11 KiB
Rust

use super::{Builtin, GlobalFunctionMap};
use num_bigint::BigInt;
use num_traits::{Signed, ToPrimitive, Zero};
#[cfg(feature = "random")]
use rand::{distributions::Alphanumeric, thread_rng, Rng};
use crate::args::CallArgs;
use crate::common::QuoteKind;
use crate::error::SassResult;
use crate::interner::{keywords::EMPTY_STRING, InternedString};
use crate::scope::Scope;
use crate::selector::Selector;
use crate::unit::Unit;
use crate::value::{Number, Value};
fn to_upper_case(
mut args: CallArgs,
scope: &Scope,
super_selector: &Selector,
) -> SassResult<Value> {
args.max_args(1)?;
match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, q) => {
let mut i = i.resolve();
i.make_ascii_uppercase();
Ok(Value::Ident(InternedString::get_or_intern(i), q))
}
v => Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into()),
}
}
fn to_lower_case(
mut args: CallArgs,
scope: &Scope,
super_selector: &Selector,
) -> SassResult<Value> {
args.max_args(1)?;
match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, q) => {
let mut i = i.resolve();
i.make_ascii_lowercase();
Ok(Value::Ident(InternedString::get_or_intern(i), q))
}
v => Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into()),
}
}
fn str_length(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(1)?;
match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, _) => Ok(Value::Dimension(
Number::from(i.resolve().chars().count()),
Unit::None,
)),
v => Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into()),
}
}
fn quote(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(1)?;
match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, _) => Ok(Value::Ident(i, QuoteKind::Quoted)),
v => Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into()),
}
}
fn unquote(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(1)?;
match arg!(args, scope, super_selector, 0, "string") {
i @ Value::Ident(..) => Ok(i.unquote()),
v => Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into()),
}
}
fn str_slice(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(3)?;
let (string, quotes) = match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(s, q) => (s, q),
v => {
return Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
let str_len = string.resolve().chars().count();
let start = match arg!(args, scope, super_selector, 1, "start-at") {
Value::Dimension(n, Unit::None) if n.is_decimal() => {
return Err((format!("{} is not an int.", n), args.span()).into())
}
Value::Dimension(n, Unit::None) if n.is_positive() => {
n.to_integer().to_usize().unwrap_or(str_len + 1)
}
Value::Dimension(n, Unit::None) if n.is_zero() => 1_usize,
Value::Dimension(n, Unit::None) if n < -Number::from(str_len) => 1_usize,
Value::Dimension(n, Unit::None) => (n.to_integer() + BigInt::from(str_len + 1))
.to_usize()
.unwrap(),
v @ Value::Dimension(..) => {
return Err((
format!(
"$start: Expected {} to have no units.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
v => {
return Err((
format!(
"$start-at: {} is not a number.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
let mut end = match arg!(args, scope, super_selector, 2, "end-at" = Value::Null) {
Value::Dimension(n, Unit::None) if n.is_decimal() => {
return Err((format!("{} is not an int.", n), args.span()).into())
}
Value::Dimension(n, Unit::None) if n.is_positive() => {
n.to_integer().to_usize().unwrap_or(str_len + 1)
}
Value::Dimension(n, Unit::None) if n.is_zero() => 0_usize,
Value::Dimension(n, Unit::None) if n < -Number::from(str_len) => 0_usize,
Value::Dimension(n, Unit::None) => (n.to_integer() + BigInt::from(str_len + 1))
.to_usize()
.unwrap_or(str_len + 1),
v @ Value::Dimension(..) => {
return Err((
format!(
"$end: Expected {} to have no units.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
Value::Null => str_len,
v => {
return Err((
format!(
"$end-at: {} is not a number.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
if end > str_len {
end = str_len;
}
if start > end || start > str_len {
Ok(Value::Ident(*EMPTY_STRING, quotes))
} else {
Ok(Value::Ident(
InternedString::get_or_intern(
string
.resolve()
.chars()
.skip(start - 1)
.take(end - start + 1)
.collect::<String>(),
),
quotes,
))
}
}
fn str_index(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(2)?;
let s1 = match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, _) => i.resolve(),
v => {
return Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
let substr = match arg!(args, scope, super_selector, 1, "substring") {
Value::Ident(i, _) => i.resolve(),
v => {
return Err((
format!(
"$substring: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
Ok(match s1.find(&substr) {
Some(v) => Value::Dimension(Number::from(v + 1), Unit::None),
None => Value::Null,
})
}
fn str_insert(mut args: CallArgs, scope: &Scope, super_selector: &Selector) -> SassResult<Value> {
args.max_args(3)?;
let (s1, quotes) = match arg!(args, scope, super_selector, 0, "string") {
Value::Ident(i, q) => (i.resolve().to_string(), q),
v => {
return Err((
format!(
"$string: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
let substr = match arg!(args, scope, super_selector, 1, "insert") {
Value::Ident(i, _) => i.resolve().to_string(),
v => {
return Err((
format!(
"$insert: {} is not a string.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
};
let index = match arg!(args, scope, super_selector, 2, "index") {
Value::Dimension(n, Unit::None) if n.is_decimal() => {
return Err((format!("$index: {} is not an int.", n), args.span()).into())
}
Value::Dimension(n, Unit::None) => n,
v @ Value::Dimension(..) => {
return Err((
format!(
"$index: Expected {} to have no units.",
v.to_css_string(args.span())?
),
args.span(),
)
.into())
}
v => {
return Err((
format!("$index: {} is not a number.", v.to_css_string(args.span())?),
args.span(),
)
.into())
}
};
if s1.is_empty() {
return Ok(Value::Ident(InternedString::get_or_intern(substr), quotes));
}
let len = s1.chars().count();
// Insert substring at char position, rather than byte position
let insert = |idx, s1: String, s2| {
s1.chars()
.enumerate()
.map(|(i, c)| {
if i + 1 == idx {
c.to_string() + s2
} else if idx == 0 && i == 0 {
s2.to_string() + &c.to_string()
} else {
c.to_string()
}
})
.collect::<String>()
};
let string = if index.is_positive() {
insert(
index
.to_integer()
.to_usize()
.unwrap_or(len + 1)
.min(len + 1)
- 1,
s1,
&substr,
)
} else if index.is_zero() {
insert(0, s1, &substr)
} else {
let idx = index.abs().to_integer().to_usize().unwrap_or(len + 1);
if idx > len {
insert(0, s1, &substr)
} else {
insert(len - idx + 1, s1, &substr)
}
};
Ok(Value::Ident(InternedString::get_or_intern(string), quotes))
}
#[cfg(feature = "random")]
fn unique_id(args: CallArgs, _: &Scope, _: &Selector) -> SassResult<Value> {
args.max_args(0)?;
let mut rng = thread_rng();
let string: String = std::iter::repeat(())
.map(|()| rng.sample(Alphanumeric))
.take(7)
.collect();
Ok(Value::Ident(
InternedString::get_or_intern(string),
QuoteKind::None,
))
}
pub(crate) fn declare(f: &mut GlobalFunctionMap) {
f.insert("to-upper-case", Builtin::new(to_upper_case));
f.insert("to-lower-case", Builtin::new(to_lower_case));
f.insert("str-length", Builtin::new(str_length));
f.insert("quote", Builtin::new(quote));
f.insert("unquote", Builtin::new(unquote));
f.insert("str-slice", Builtin::new(str_slice));
f.insert("str-index", Builtin::new(str_index));
f.insert("str-insert", Builtin::new(str_insert));
#[cfg(feature = "random")]
f.insert("unique-id", Builtin::new(unique_id));
}