diff options
| -rw-r--r-- | askama_shared/src/generator.rs | 56 | ||||
| -rw-r--r-- | askama_shared/src/parser.rs | 7 | ||||
| -rw-r--r-- | testing/tests/loops.rs | 18 |
3 files changed, 51 insertions, 30 deletions
diff --git a/askama_shared/src/generator.rs b/askama_shared/src/generator.rs index 0c2e854..5c72934 100644 --- a/askama_shared/src/generator.rs +++ b/askama_shared/src/generator.rs @@ -605,52 +605,50 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> { let flushed = self.write_buf_writable(buf)?; buf.writeln("{")?; - buf.writeln("let mut _did_not_loop = true;")?; - buf.write("for ("); - self.visit_target(buf, true, true, &loop_block.var); + buf.writeln("let mut _did_loop = false;")?; match loop_block.iter { - Expr::Range(_, _, _) => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new({}) {{", - expr_code - )), - Expr::Array(..) => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new({}.iter()) {{", - expr_code - )), + Expr::Range(_, _, _) => buf.writeln(&format!("let _iter = {};", expr_code)), + Expr::Array(..) => buf.writeln(&format!("let _iter = {}.iter();", expr_code)), // If `iter` is a call then we assume it's something that returns // an iterator. If not then the user can explicitly add the needed // call without issues. - Expr::MethodCall(..) | Expr::PathCall(..) | Expr::Index(..) => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new(({}).into_iter()) {{", - expr_code - )), + Expr::MethodCall(..) | Expr::PathCall(..) | Expr::Index(..) => { + buf.writeln(&format!("let _iter = ({}).into_iter();", expr_code)) + } // If accessing `self` then it most likely needs to be // borrowed, to prevent an attempt of moving. - _ if expr_code.starts_with("self.") => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new(((&{}).into_iter())) {{", - expr_code - )), + _ if expr_code.starts_with("self.") => { + buf.writeln(&format!("let _iter = (&{}).into_iter();", expr_code)) + } // If accessing a field then it most likely needs to be // borrowed, to prevent an attempt of moving. - Expr::Attr(..) => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new(((&{}).into_iter())) {{", - expr_code - )), + Expr::Attr(..) => buf.writeln(&format!("let _iter = (&{}).into_iter();", expr_code)), // Otherwise, we borrow `iter` assuming that it implements `IntoIterator`. - _ => buf.writeln(&format!( - ", _loop_item) in ::askama::helpers::TemplateLoop::new(({}).into_iter()) {{", - expr_code - )), + _ => buf.writeln(&format!("let _iter = ({}).into_iter();", expr_code)), }?; + if let Some(cond) = &loop_block.cond { + self.locals.push(); + buf.write("let _iter = _iter.filter(|"); + self.visit_target(buf, true, true, &loop_block.var); + buf.write("| -> bool {"); + self.visit_expr(buf, cond)?; + buf.writeln("});")?; + self.locals.pop(); + } + + self.locals.push(); + buf.write("for ("); + self.visit_target(buf, true, true, &loop_block.var); + buf.writeln(", _loop_item) in ::askama::helpers::TemplateLoop::new(_iter) {")?; - buf.writeln("_did_not_loop = false;")?; + buf.writeln("_did_loop = true;")?; let mut size_hint1 = self.handle(ctx, &loop_block.body, buf, AstLevel::Nested)?; self.handle_ws(loop_block.ws2); size_hint1 += self.write_buf_writable(buf)?; self.locals.pop(); buf.writeln("}")?; - buf.writeln("if _did_not_loop {")?; + buf.writeln("if !_did_loop {")?; self.locals.push(); let mut size_hint2 = self.handle(ctx, &loop_block.else_block, buf, AstLevel::Nested)?; self.handle_ws(loop_block.ws3); diff --git a/askama_shared/src/parser.rs b/askama_shared/src/parser.rs index 90c2fe3..34a391d 100644 --- a/askama_shared/src/parser.rs +++ b/askama_shared/src/parser.rs @@ -38,6 +38,7 @@ pub struct Loop<'a> { pub ws1: Ws, pub var: Target<'a>, pub iter: Expr<'a>, + pub cond: Option<Expr<'a>>, pub body: Vec<Node<'a>>, pub ws2: Ws, pub else_block: Vec<Node<'a>>, @@ -914,6 +915,7 @@ fn parse_loop_content<'a>(i: &'a [u8], s: &State<'_>) -> IResult<&'a [u8], Vec<N } fn block_for<'a>(i: &'a [u8], s: &State<'_>) -> IResult<&'a [u8], Node<'a>> { + let if_cond = preceded(ws(tag("if")), cut(ws(expr_any))); let else_block = |i| { let mut p = preceded( ws(tag("else")), @@ -938,6 +940,7 @@ fn block_for<'a>(i: &'a [u8], s: &State<'_>) -> IResult<&'a [u8], Node<'a>> { ws(tag("in")), cut(tuple(( ws(expr_any), + opt(if_cond), opt(char('-')), |i| tag_block_end(i, s), cut(tuple(( @@ -953,7 +956,8 @@ fn block_for<'a>(i: &'a [u8], s: &State<'_>) -> IResult<&'a [u8], Node<'a>> { ))), ))), )); - let (i, (pws1, _, (var, _, (iter, nws1, _, (body, (_, pws2, else_block, _, nws2)))))) = p(i)?; + let (i, (pws1, _, (var, _, (iter, cond, nws1, _, (body, (_, pws2, else_block, _, nws2)))))) = + p(i)?; let (nws3, else_block, pws3) = else_block.unwrap_or_default(); Ok(( i, @@ -961,6 +965,7 @@ fn block_for<'a>(i: &'a [u8], s: &State<'_>) -> IResult<&'a [u8], Node<'a>> { ws1: Ws(pws1.is_some(), nws1.is_some()), var, iter, + cond, body, ws2: Ws(pws2.is_some(), nws3), else_block, diff --git a/testing/tests/loops.rs b/testing/tests/loops.rs index f014068..4a02153 100644 --- a/testing/tests/loops.rs +++ b/testing/tests/loops.rs @@ -417,3 +417,21 @@ fn test_for_cycle_empty() { }; assert!(t.render().is_err()) } + +#[derive(Template)] +#[template( + source = "{% for i in 0..limit if i % 2 == 1 %}{{i}}.{% else %}:({% endfor %}", + ext = "txt" +)] +struct ForInIf { + limit: usize, +} + +#[test] +fn test_for_in_if() { + let t = ForInIf { limit: 10 }; + assert_eq!(t.render().unwrap(), "1.3.5.7.9."); + + let t = ForInIf { limit: 1 }; + assert_eq!(t.render().unwrap(), ":("); +} |