From e018c4a4273063989041c1dc1b6c6878d03a56a6 Mon Sep 17 00:00:00 2001
From: mbuscemi <matthew.buscemi@gmail.com>
Date: Mon, 22 Mar 2021 03:43:29 -0700
Subject: added paragraphbreaks function

---
 askama_shared/src/filters/mod.rs | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

(limited to 'askama_shared')

diff --git a/askama_shared/src/filters/mod.rs b/askama_shared/src/filters/mod.rs
index 58bcc47..ce87fd9 100644
--- a/askama_shared/src/filters/mod.rs
+++ b/askama_shared/src/filters/mod.rs
@@ -47,7 +47,7 @@ const URLENCODE_SET: &AsciiSet = &URLENCODE_STRICT_SET.remove(b'/');
 // 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; 26] = [
+pub const BUILT_IN_FILTERS: [&str; 27] = [
     "abs",
     "capitalize",
     "center",
@@ -62,6 +62,7 @@ pub const BUILT_IN_FILTERS: [&str; 26] = [
     "join",
     "linebreaks",
     "linebreaksbr",
+    "paragraphbreaks",
     "lower",
     "lowercase",
     "safe",
@@ -212,6 +213,18 @@ pub fn linebreaksbr<T: fmt::Display>(s: T) -> Result<String> {
     Ok(s.replace("\n", "<br/>"))
 }
 
+/// Replaces only paragraph breaks in plain text with appropriate HTML
+///
+/// A new line followed by a blank line becomes a paragraph break `<p>`.
+/// Paragraph tags only wrap content; empty paragraphs are removed.
+/// No `<br/>` tags are added.
+pub fn paragraphbreaks<T: fmt::Display>(s: T) -> Result<String> {
+    let s = s.to_string();
+    let linebroken = s.replace("\n\n", "</p><p>").replace("<p></p>", "");
+
+    Ok(format!("<p>{}</p>", linebroken))
+}
+
 /// Converts to lowercase
 pub fn lower<T: fmt::Display>(s: T) -> Result<String> {
     let s = s.to_string();
@@ -457,6 +470,22 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_paragraphbreaks() {
+        assert_eq!(
+            paragraphbreaks(&"Foo\nBar Baz").unwrap(),
+            "<p>Foo\nBar Baz</p>"
+        );
+        assert_eq!(
+            paragraphbreaks(&"Foo\nBar\n\nBaz").unwrap(),
+            "<p>Foo\nBar</p><p>Baz</p>"
+        );
+        assert_eq!(
+            paragraphbreaks(&"Foo\n\n\n\n\nBar\n\nBaz").unwrap(),
+            "<p>Foo</p><p>\nBar</p><p>Baz</p>"
+        );
+    }
+
     #[test]
     fn test_lower() {
         assert_eq!(lower(&"Foo").unwrap(), "foo");
-- 
cgit