diff options
| -rw-r--r-- | askama_shared/src/generator.rs | 39 | ||||
| -rw-r--r-- | askama_shared/src/parser.rs | 32 |
2 files changed, 54 insertions, 17 deletions
diff --git a/askama_shared/src/generator.rs b/askama_shared/src/generator.rs index 24a4a71..fc94977 100644 --- a/askama_shared/src/generator.rs +++ b/askama_shared/src/generator.rs @@ -3,7 +3,8 @@ use crate::filters; use crate::heritage::{Context, Heritage}; use crate::input::{Source, TemplateInput}; use crate::parser::{ - parse, Cond, Expr, MatchParameter, MatchParameters, MatchVariant, Node, Target, When, Ws, + parse, Cond, CondTest, Expr, MatchParameter, MatchParameters, MatchVariant, Node, Target, When, + Ws, }; use proc_macro2::Span; @@ -483,23 +484,38 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> { self.locals.pop(); } + self.locals.push(); let mut arm_size = 0; - if let Some(expr) = cond { + if let Some(CondTest { target, expr }) = cond { if i == 0 { buf.write("if "); } else { buf.dedent()?; buf.write("} else if "); } - // The following syntax `*(&(...) as &bool)` is used to - // trigger Rust's automatic dereferencing, to coerce - // e.g. `&&&&&bool` to `bool`. First `&(...) as &bool` - // coerces e.g. `&&&bool` to `&bool`. Then `*(&bool)` - // finally dereferences it to `bool`. - buf.write("*(&("); - let expr_code = self.visit_expr_root(expr)?; - buf.write(&expr_code); - buf.write(") as &bool)"); + + if let Some((variant, params)) = target { + let mut expr_buf = Buffer::new(0); + self.visit_expr(&mut expr_buf, expr)?; + buf.write("let "); + self.visit_match_variant(buf, variant); + if let Some(params) = params { + self.visit_match_params(buf, params); + } + buf.write(" = &("); + buf.write(&expr_buf.buf); + buf.write(")"); + } else { + // The following syntax `*(&(...) as &bool)` is used to + // trigger Rust's automatic dereferencing, to coerce + // e.g. `&&&&&bool` to `bool`. First `&(...) as &bool` + // coerces e.g. `&&&bool` to `&bool`. Then `*(&bool)` + // finally dereferences it to `bool`. + buf.write("*(&("); + let expr_code = self.visit_expr_root(expr)?; + buf.write(&expr_code); + buf.write(") as &bool)"); + } } else { buf.dedent()?; buf.write("} else"); @@ -507,7 +523,6 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> { } buf.writeln(" {")?; - self.locals.push(); arm_size += self.handle(ctx, nodes, buf, AstLevel::Nested)?; arm_sizes.push(arm_size); diff --git a/askama_shared/src/parser.rs b/askama_shared/src/parser.rs index ea13738..3c5a86c 100644 --- a/askama_shared/src/parser.rs +++ b/askama_shared/src/parser.rs @@ -18,7 +18,7 @@ pub enum Node<'a> { Call(Ws, Option<&'a str>, &'a str, Vec<Expr<'a>>), LetDecl(Ws, Target<'a>), Let(Ws, Target<'a>, Expr<'a>), - Cond(Vec<(Ws, Option<Expr<'a>>, Vec<Node<'a>>)>, Ws), + Cond(Vec<Cond<'a>>, Ws), Match(Ws, Expr<'a>, Vec<When<'a>>, Ws), Loop(Ws, Target<'a>, Expr<'a>, Vec<Node<'a>>, Ws), Extends(Expr<'a>), @@ -144,7 +144,13 @@ pub enum Target<'a> { #[derive(Clone, Copy, Debug, PartialEq)] pub struct Ws(pub bool, pub bool); -pub type Cond<'a> = (Ws, Option<Expr<'a>>, Vec<Node<'a>>); +pub type Cond<'a> = (Ws, Option<CondTest<'a>>, Vec<Node<'a>>); + +#[derive(Debug, PartialEq)] +pub struct CondTest<'a> { + pub target: Option<(MatchVariant<'a>, Option<MatchParameters<'a>>)>, + pub expr: Expr<'a>, +} fn ws<F, I, O, E>(mut inner: F) -> impl FnMut(I) -> IResult<I, O, E> where @@ -724,9 +730,25 @@ fn block_call(i: &[u8]) -> IResult<&[u8], Node> { )) } -fn cond_if(i: &[u8]) -> IResult<&[u8], Expr> { - let (i, (_, cond)) = tuple((ws(tag("if")), ws(expr_any)))(i)?; - Ok((i, cond)) +fn cond_if(i: &[u8]) -> IResult<&[u8], CondTest> { + let mut p = tuple(( + ws(tag("if")), + opt(tuple(( + ws(alt((tag("let"), tag("set")))), + ws(match_variant), + opt(alt((match_simple_parameters, match_named_parameters))), + ws(tag("=")), + ))), + ws(expr_any), + )); + let (i, (_, dest, expr)) = p(i)?; + Ok(( + i, + CondTest { + target: dest.map(|(_, variant, params, _)| (variant, params)), + expr, + }, + )) } fn cond_block<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Cond<'a>> { |