From 42c4cb1d877d696bb97aa2e9402429dad42d7d66 Mon Sep 17 00:00:00 2001
From: Andrew Dona-Couch <hi@andrewcou.ch>
Date: Wed, 8 Jul 2020 17:03:02 +0000
Subject: Add fmt filter that swaps the first two arguments to format!().
This allows a more natural filter usage: `{{ val | fmt("{:?}") }}`
as well as enabling convenient filter composition:
`{{ price | to_f64 | fmt("${:.2}") | center }}`
---
askama_shared/src/filters/mod.rs | 24 +++++++++++++++++++++++-
askama_shared/src/generator.rs | 18 ++++++++++++++++++
2 files changed, 41 insertions(+), 1 deletion(-)
(limited to 'askama_shared')
diff --git a/askama_shared/src/filters/mod.rs b/askama_shared/src/filters/mod.rs
index 2604ed9..7253e4b 100644
--- a/askama_shared/src/filters/mod.rs
+++ b/askama_shared/src/filters/mod.rs
@@ -58,13 +58,14 @@ const ENCODE_SET: &AsciiSet = &NON_ALPHANUMERIC
// Askama or should refer to a local `filters` module. It should contain all the
// filters shipped with Askama, even the optional ones (since optional inclusion
// in the const vector based on features seems impossible right now).
-pub const BUILT_IN_FILTERS: [&str; 24] = [
+pub const BUILT_IN_FILTERS: [&str; 25] = [
"abs",
"capitalize",
"center",
"e",
"escape",
"filesizeformat",
+ "fmt",
"format",
"indent",
"into_f64",
@@ -137,12 +138,33 @@ pub fn urlencode(s: &dyn fmt::Display) -> Result<String> {
Ok(utf8_percent_encode(&s, ENCODE_SET).to_string())
}
+/// Formats arguments according to the specified format
+///
+/// The *second* argument to this filter must be a string literal (as in normal
+/// Rust). The two arguments are passed through to the `format!()`
+/// [macro](https://doc.rust-lang.org/stable/std/macro.format.html) by
+/// the Askama code generator, but the order is swapped to support filter
+/// composition.
+///
+/// ```ignore
+/// {{ value | fmt("{:?}") }}
+/// ```
+///
+/// Compare with [format](./fn.format.html).
+pub fn fmt() {}
+
/// Formats arguments according to the specified format
///
/// The first argument to this filter must be a string literal (as in normal
/// Rust). All arguments are passed through to the `format!()`
/// [macro](https://doc.rust-lang.org/stable/std/macro.format.html) by
/// the Askama code generator.
+///
+/// ```ignore
+/// {{ "{:?}{:?}" | format(value, other_value) }}
+/// ```
+///
+/// Compare with [fmt](./fn.fmt.html).
pub fn format() {}
/// Replaces line breaks in plain text with appropriate HTML
diff --git a/askama_shared/src/generator.rs b/askama_shared/src/generator.rs
index 82f68ff..e45acb6 100644
--- a/askama_shared/src/generator.rs
+++ b/askama_shared/src/generator.rs
@@ -999,6 +999,9 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> {
if name == "format" {
self._visit_format_filter(buf, args);
return DisplayWrap::Unwrapped;
+ } else if name == "fmt" {
+ self._visit_fmt_filter(buf, args);
+ return DisplayWrap::Unwrapped;
} else if name == "join" {
self._visit_join_filter(buf, args);
return DisplayWrap::Unwrapped;
@@ -1038,6 +1041,21 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> {
buf.write(")");
}
+ fn _visit_fmt_filter(&mut self, buf: &mut Buffer, args: &[Expr]) {
+ buf.write("format!(");
+ if let Some(Expr::StrLit(v)) = args.get(1) {
+ self.visit_str_lit(buf, v);
+ buf.write(", ");
+ } else {
+ panic!("invalid expression type for fmt filter");
+ }
+ self._visit_args(buf, &args[0..1]);
+ if args.len() > 2 {
+ panic!("only two arguments allowed to fmt filter");
+ }
+ buf.write(")");
+ }
+
// Force type coercion on first argument to `join` filter (see #39).
fn _visit_join_filter(&mut self, buf: &mut Buffer, args: &[Expr]) {
buf.write("::askama::filters::join((&");
--
cgit