Don't URL-decode path segments

3 files changed, 28 insertions, 23 deletions

diff --git a/dhall_syntax/Cargo.toml b/dhall_syntax/Cargo.toml
index 08d0195..1da10c7 100644
--- a/dhall_syntax/Cargo.toml
+++ b/dhall_syntax/Cargo.toml
@@ -10,7 +10,7 @@ doctest = false
 
 [dependencies]
 itertools = "0.8.0"
-percent-encoding = "1.0.1"
+percent-encoding = "2.1.0"
 pest = "2.1"
 either = "1.5.2"
 take_mut = "0.2.2"
diff --git a/dhall_syntax/src/parser.rs b/dhall_syntax/src/parser.rs
index 24ecc1e..53fd68a 100644
--- a/dhall_syntax/src/parser.rs
+++ b/dhall_syntax/src/parser.rs
@@ -669,12 +669,29 @@ make_parser! {
     rule!(unquoted_path_component<&'a str>; captured_str!(s) => s);
     rule!(quoted_path_component<&'a str>; captured_str!(s) => s);
     rule!(path_component<String>; children!(
-        [unquoted_path_component(s)] => {
-            percent_encoding::percent_decode(s.as_bytes())
-                .decode_utf8_lossy()
-                .into_owned()
+        [unquoted_path_component(s)] => s.to_string(),
+        [quoted_path_component(s)] => {
+            const RESERVED: &percent_encoding::AsciiSet =
+                &percent_encoding::CONTROLS
+                .add(b'=').add(b':').add(b'/').add(b'?')
+                .add(b'#').add(b'[').add(b']').add(b'@')
+                .add(b'!').add(b'$').add(b'&').add(b'\'')
+                .add(b'(').add(b')').add(b'*').add(b'+')
+                .add(b',').add(b';');
+            s.chars()
+                .map(|c| {
+                    // Percent-encode ascii chars
+                    if c.is_ascii() {
+                        percent_encoding::utf8_percent_encode(
+                            &c.to_string(),
+                            RESERVED,
+                        ).to_string()
+                    } else {
+                        c.to_string()
+                    }
+                })
+                .collect()
         },
-        [quoted_path_component(s)] => s.to_string(),
     ));
     rule!(path<Vec<String>>; children!(
         [path_component(components)..] => {
diff --git a/dhall_syntax/src/printer.rs b/dhall_syntax/src/printer.rs
index 8571d11..f3dc648 100644
--- a/dhall_syntax/src/printer.rs
+++ b/dhall_syntax/src/printer.rs
@@ -360,15 +360,9 @@ impl<SubExpr: Display> Display for Import<SubExpr> {
         use FilePrefix::*;
         use ImportLocation::*;
         use ImportMode::*;
-        let fmt_remote_path_component = |s: &str| -> String {
-            use percent_encoding::{
-                utf8_percent_encode, PATH_SEGMENT_ENCODE_SET,
-            };
-            utf8_percent_encode(s, PATH_SEGMENT_ENCODE_SET).to_string()
-        };
-        let fmt_local_path_component = |s: &str| -> String {
+        let quote_if_needed = |s: &str| -> String {
             if s.chars().all(|c| c.is_ascii_alphanumeric()) {
-                s.to_owned()
+                s.to_string()
             } else {
                 format!("\"{}\"", s)
             }
@@ -383,19 +377,13 @@ impl<SubExpr: Display> Display for Import<SubExpr> {
                     Absolute => "",
                 };
                 write!(f, "{}/", prefix)?;
-                let path: String = path
-                    .iter()
-                    .map(|c| fmt_local_path_component(c.as_ref()))
-                    .join("/");
+                let path: String =
+                    path.iter().map(|c| quote_if_needed(&*c)).join("/");
                 f.write_str(&path)?;
             }
             Remote(url) => {
                 write!(f, "{}://{}/", url.scheme, url.authority,)?;
-                let path: String = url
-                    .path
-                    .iter()
-                    .map(|c| fmt_remote_path_component(c.as_ref()))
-                    .join("/");
+                let path: String = url.path.iter().join("/");
                 f.write_str(&path)?;
                 if let Some(q) = &url.query {
                     write!(f, "?{}", q)?