From 2b645f7be4d0888bb1f6c738f3c571e95f83cf48 Mon Sep 17 00:00:00 2001
From: Quentin Gliech <quenting@element.io>
Date: Tue, 3 Oct 2023 09:43:58 +0200
Subject: [PATCH] templates: escape translation placeholders

---
 crates/i18n/src/sprintf/formatter.rs | 39 ++++++++++++++++++++++++++--
 crates/i18n/src/sprintf/mod.rs       |  5 ++--
 crates/templates/Cargo.toml          |  2 +-
 crates/templates/src/functions.rs    | 24 ++++++++++++++---
 4 files changed, 60 insertions(+), 10 deletions(-)

diff --git a/crates/i18n/src/sprintf/formatter.rs b/crates/i18n/src/sprintf/formatter.rs
index e369b7e5..259f22cd 100644
--- a/crates/i18n/src/sprintf/formatter.rs
+++ b/crates/i18n/src/sprintf/formatter.rs
@@ -484,11 +484,22 @@ fn format_value(value: &Value, placeholder: &Placeholder) -> Result<String, Form
     }
 }
 
-enum FormattedMessagePart<'a> {
+pub enum FormattedMessagePart<'a> {
+    /// A literal text part of the message. It should not be escaped.
     Text(&'a str),
+    /// A placeholder part of the message. It should be escaped.
     Placeholder(String),
 }
 
+impl<'a> FormattedMessagePart<'a> {
+    fn len(&self) -> usize {
+        match self {
+            FormattedMessagePart::Text(text) => text.len(),
+            FormattedMessagePart::Placeholder(placeholder) => placeholder.len(),
+        }
+    }
+}
+
 impl std::fmt::Display for FormattedMessagePart<'_> {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         match self {
@@ -500,6 +511,27 @@ impl std::fmt::Display for FormattedMessagePart<'_> {
 
 pub struct FormattedMessage<'a> {
     parts: Vec<FormattedMessagePart<'a>>,
+    total_len: usize,
+}
+
+impl FormattedMessage<'_> {
+    /// Returns the length of the formatted message (not the number of parts).
+    #[must_use]
+    pub fn len(&self) -> usize {
+        self.total_len
+    }
+
+    /// Returns `true` if the formatted message is empty.
+    #[must_use]
+    pub fn is_empty(&self) -> bool {
+        self.total_len == 0
+    }
+
+    /// Returns the list of parts of the formatted message.
+    #[must_use]
+    pub fn parts(&self) -> &[FormattedMessagePart<'_>] {
+        &self.parts
+    }
 }
 
 impl std::fmt::Display for FormattedMessage<'_> {
@@ -529,6 +561,8 @@ impl Message {
         // Holds the current index of the placeholder we are formatting, which is used
         // by non-named, non-indexed placeholders
         let mut current_placeholder = 0usize;
+        // Compute the total length of the formatted message
+        let mut total_len = 0usize;
         for part in self.parts() {
             let formatted = match part {
                 Part::Percent => FormattedMessagePart::Text("%"),
@@ -563,9 +597,10 @@ impl Message {
                     FormattedMessagePart::Placeholder(formatted)
                 }
             };
+            total_len += formatted.len();
             parts.push(formatted);
         }
 
-        Ok(FormattedMessage { parts })
+        Ok(FormattedMessage { parts, total_len })
     }
 }
diff --git a/crates/i18n/src/sprintf/mod.rs b/crates/i18n/src/sprintf/mod.rs
index f9b1d8f1..20a07f78 100644
--- a/crates/i18n/src/sprintf/mod.rs
+++ b/crates/i18n/src/sprintf/mod.rs
@@ -19,10 +19,9 @@ mod formatter;
 mod message;
 mod parser;
 
-use thiserror::Error;
-
 pub use self::{
     argument::{Argument, List as ArgumentList},
+    formatter::{FormatError, FormattedMessage, FormattedMessagePart},
     message::Message,
 };
 
@@ -79,7 +78,7 @@ pub(crate) use arg_list_inner;
 #[allow(unused_imports)]
 pub(crate) use sprintf;
 
-#[derive(Debug, Error)]
+#[derive(Debug, thiserror::Error)]
 #[error(transparent)]
 enum Error {
     Format(#[from] self::formatter::FormatError),
diff --git a/crates/templates/Cargo.toml b/crates/templates/Cargo.toml
index a16e5221..cb798c14 100644
--- a/crates/templates/Cargo.toml
+++ b/crates/templates/Cargo.toml
@@ -16,7 +16,7 @@ walkdir = "2.4.0"
 anyhow.workspace = true
 thiserror.workspace = true
 
-minijinja = { workspace = true, features = ["loader", "json", "speedups"] }
+minijinja = { workspace = true, features = ["loader", "json", "speedups", "unstable_machinery"] }
 serde.workspace = true
 serde_json.workspace = true
 serde_urlencoded = "0.7.1"
diff --git a/crates/templates/src/functions.rs b/crates/templates/src/functions.rs
index 219c5483..edafcaf6 100644
--- a/crates/templates/src/functions.rs
+++ b/crates/templates/src/functions.rs
@@ -25,10 +25,12 @@ use std::{
 };
 
 use camino::Utf8Path;
-use mas_i18n::{Argument, ArgumentList, DataLocale, Translator};
+use mas_i18n::{sprintf::FormattedMessagePart, Argument, ArgumentList, DataLocale, Translator};
 use mas_router::UrlBuilder;
 use mas_spa::ViteManifest;
 use minijinja::{
+    escape_formatter,
+    machinery::make_string_output,
     value::{from_args, Kwargs, Object, SeqObject, ViaDeserialize},
     Error, ErrorKind, State, Value,
 };
@@ -258,12 +260,26 @@ impl Object for Translate {
             .collect();
         let list = res?;
 
-        let formatted = message.format(&list).map_err(|e| {
+        let formatted = message.format_(&list).map_err(|e| {
             Error::new(ErrorKind::InvalidOperation, "Could not format message").with_source(e)
         })?;
 
-        // TODO: escape
-        Ok(Value::from_safe_string(formatted))
+        let mut buf = String::with_capacity(formatted.len());
+        let mut output = make_string_output(&mut buf);
+        for part in formatted.parts() {
+            match part {
+                FormattedMessagePart::Text(text) => {
+                    // Literal text, just write it
+                    output.write_str(text)?;
+                }
+                FormattedMessagePart::Placeholder(placeholder) => {
+                    // Placeholder, escape it
+                    escape_formatter(&mut output, state, &placeholder.as_str().into())?;
+                }
+            }
+        }
+
+        Ok(Value::from_safe_string(buf))
     }
 }