feat: non-strict mode replaces invalid UTF-8 (#62)

This change makes non-strict mode percent-decode utf-8 lossily.
This means that invalid UTF-8 percent encoded sequences, such as `%E9`, are
decoded as the unicode replacement character (� `U+FFFD`).

Refs: https://github.com/samscott89/serde_qs/issues/43

1 files changed, 9 insertions, 1 deletions

diff --git a/src/de/parse.rs b/src/de/parse.rs
index 5c85b12..fe14bb4 100644
--- a/src/de/parse.rs
+++ b/src/de/parse.rs
@@ -242,8 +242,16 @@ impl<'a> Parser<'a> {
     /// present.
     fn collect_str(&mut self) -> Result<Cow<'a, str>> {
         let replaced = replace_plus(&self.inner[self.acc.0..self.acc.1 - 1]);
+        let decoder = percent_encoding::percent_decode(&replaced);
+
+        let maybe_decoded = if self.strict {
+            decoder.decode_utf8()?
+        } else {
+            decoder.decode_utf8_lossy()
+        };
+
         let ret: Result<Cow<'a, str>> =
-            match percent_encoding::percent_decode(&replaced).decode_utf8()? {
+            match maybe_decoded {
                 Cow::Borrowed(_) => {
                     match replaced {
                         Cow::Borrowed(_) => {