Fix router parser not parsing identifiers (#234)

* Fix router parser not parsing identifiers

* Update trybuild

packages/sycamore-reactive/src/effect.rs

@@ -374,7 +374,8 @@ where
 
 /// An alternative to [`Signal::new`] that uses a reducer to get the next value.
 ///
-/// It uses a reducer function that takes the previous value and a message and returns the next value.
+/// It uses a reducer function that takes the previous value and a message and returns the next
+/// value.
 ///
 /// Returns a [`StateHandle`] and a dispatch function to send messages to the reducer.
 ///

packages/sycamore-router-macro/Cargo.toml

@@ -17,12 +17,13 @@ proc-macro = true
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-nom = "6.2.1"
+nom = "7.0.0"
 proc-macro2 = "1.0.28"
 quote = "1.0.9"
 syn = { version = "1.0.74", features = ["full"] }
+unicode-xid = "0.2.2"
 
 [dev-dependencies]
 expect-test = "1.1.0"
-sycamore-router = {path = "../sycamore-router"}
+sycamore-router = { path = "../sycamore-router" }
 trybuild = "1.0.45"

packages/sycamore-router-macro/src/parser.rs

@@ -1,8 +1,8 @@
 use nom::branch::alt;
-use nom::bytes::complete::{tag, take_till, take_until};
-use nom::combinator::map;
-use nom::multi::separated_list0;
-use nom::sequence::delimited;
+use nom::bytes::complete::{tag, take, take_till};
+use nom::combinator::{map, recognize, verify};
+use nom::multi::{many0, separated_list0};
+use nom::sequence::{delimited, pair};
 use nom::IResult;
 
 #[derive(Debug, Clone)]
@@ -31,12 +31,30 @@ fn param(i: &str) -> IResult<&str, &str> {
     take_till(|c| c == '/')(i)
 }
 
+pub fn ident_start(s: &str) -> IResult<&str, &str> {
+    verify(take(1usize), |c: &str| {
+        let c = c.chars().next().unwrap();
+        c == '_' || unicode_xid::UnicodeXID::is_xid_start(c)
+    })(s)
+}
+
+pub fn ident_continue(s: &str) -> IResult<&str, &str> {
+    verify(take(1usize), |c: &str| {
+        unicode_xid::UnicodeXID::is_xid_continue(c.chars().next().unwrap())
+    })(s)
+}
+
+/// Parse a Rust identifier. Reference: https://doc.rust-lang.org/reference/identifiers.html
+fn ident(i: &str) -> IResult<&str, &str> {
+    recognize(pair(ident_start, many0(ident_continue)))(i)
+}
+
 fn dyn_param(i: &str) -> IResult<&str, &str> {
-    delimited(tag("<"), take_until(">"), tag(">"))(i)
+    delimited(tag("<"), ident, tag(">"))(i)
 }
 
 fn dyn_segments(i: &str) -> IResult<&str, &str> {
-    delimited(tag("<"), take_until("..>"), tag("..>"))(i)
+    delimited(tag("<"), ident, tag("..>"))(i)
 }
 
 fn segment(i: &str) -> IResult<&str, SegmentAst> {
@@ -208,6 +226,27 @@ mod tests {
         );
     }
 
+    #[test]
+    fn unnamed_dyn_param() {
+        check(
+            "/id/<_>",
+            expect![[r#"
+                (
+                    "",
+                    RoutePathAst {
+                        segments: [
+                            Param(
+                                "id",
+                            ),
+                            DynParam(
+                                "_",
+                            ),
+                        ],
+                    },
+                )"#]],
+        );
+    }
+
     #[test]
     fn dyn_segments() {
         check(
@@ -233,13 +272,37 @@ mod tests {
     fn dyn_should_eat_slash_character() {
         check(
             "/<a/b>/",
+            expect![[r#"
+                (
+                    "",
+                    RoutePathAst {
+                        segments: [
+                            Param(
+                                "<a",
+                            ),
+                            Param(
+                                "b>",
+                            ),
+                        ],
+                    },
+                )"#]],
+        );
+    }
+
+    #[test]
+    fn dyn_param_before_dyn_segment() {
+        check(
+            "/<param>/<segments..>",
             expect![[r#"
                 (
                     "",
                     RoutePathAst {
                         segments: [
                             DynParam(
-                                "a/b",
+                                "param",
+                            ),
+                            DynSegments(
+                                "segments",
                             ),
                         ],
                     },

packages/sycamore-router-macro/src/route.rs

@@ -118,7 +118,8 @@ fn impl_to(
     if expected_fields_len != variant.fields.len() {
         return Err(syn::Error::new(
             variant.fields.span(),
-            "mismatch between number of capture fields and variant fields",
+            format!("mismatch between number of capture fields and variant fields (found {} capture field(s) and {} variant field(s))",
+            expected_fields_len, variant.fields.len()),
         ));
     }
 
@@ -134,7 +135,11 @@ fn impl_to(
                         if param != &field.ident.as_ref().unwrap().to_string() {
                             return Err(syn::Error::new(
                                 field.ident.span(),
-                                "capture field name mismatch",
+                                format!(
+                                    "capture field name mismatch (expected `{}`, found `{}`)",
+                                    param,
+                                    field.ident.as_ref().unwrap()
+                                ),
                             ));
                         }
                         let param_id: Ident = syn::parse_str(param)?;
@@ -151,7 +156,11 @@ fn impl_to(
                         if param != &field.ident.as_ref().unwrap().to_string() {
                             return Err(syn::Error::new(
                                 field.ident.span(),
-                                "capture field name mismatch",
+                                format!(
+                                    "capture field name mismatch (expected `{}`, found `{}`)",
+                                    param,
+                                    field.ident.as_ref().unwrap()
+                                ),
                             ));
                         }
                         let param_id: Ident = syn::parse_str(param)?;

packages/sycamore-router-macro/tests/router/router-fail.stderr

@@ -16,34 +16,34 @@ error: not found route cannot have any fields
 13 |     NotFound(i32), // Cannot have field
    |             ^^^^^
 
-error: mismatch between number of capture fields and variant fields
+error: mismatch between number of capture fields and variant fields (found 1 capture field(s) and 0 variant field(s))
   --> $DIR/router-fail.rs:16:10
    |
 16 | #[derive(Route)]
    |          ^^^^^
    |
    = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: mismatch between number of capture fields and variant fields
+error: mismatch between number of capture fields and variant fields (found 1 capture field(s) and 0 variant field(s))
   --> $DIR/router-fail.rs:27:10
    |
 27 |     Path {}, // Missing capture field
    |          ^^
 
-error: capture field name mismatch
+error: capture field name mismatch (expected `capture`, found `not_capture`)
   --> $DIR/router-fail.rs:35:12
    |
 35 |     Path { not_capture: u32 }, // Wrong capture field name
    |            ^^^^^^^^^^^
 
-error: capture field name mismatch
+error: capture field name mismatch (expected `a`, found `b`)
   --> $DIR/router-fail.rs:43:12
    |
 43 |     Path { b: u32, a: u32 }, // Wrong order
    |            ^
 
-error: capture field name mismatch
-  --> $DIR/router-fail.rs:51:12
+error: mismatch between number of capture fields and variant fields (found 0 capture field(s) and 1 variant field(s))
+  --> $DIR/router-fail.rs:51:10
    |
 51 |     Path { a: u32 },
-   |            ^
+   |          ^^^^^^^^^^

packages/sycamore-router/src/lib.rs

@@ -452,5 +452,27 @@ mod tests {
                 Routes::NotFound
             );
         }
+
+        #[test]
+        fn router_dyn_param_before_dyn_segment() {
+            #[derive(Debug, PartialEq, Eq, Route)]
+            enum Routes {
+                #[to("/<param>/<segments..>")]
+                Path {
+                    param: String,
+                    segments: Vec<String>,
+                },
+                #[not_found]
+                NotFound,
+            }
+
+            assert_eq!(
+                Routes::match_route(&["path", "1", "2"]),
+                Routes::Path {
+                    param: "path".to_string(),
+                    segments: vec!["1".to_string(), "2".to_string()]
+                }
+            );
+        }
     }
 }

website/src/index.rs

@@ -14,11 +14,11 @@ pub fn index() -> Template<G> {
                 h1(class="text-5xl font-bold mt-20 mb-5") {
                     "Sycamore"
                 }
-    
+
                 p(class="mb-5 text-center") {
                     "A reactive library for creating web apps in Rust and WebAssembly"
                 }
-    
+
                 // region: badges
                 div(class="mb-7 flex flex-row flex-wrap justify-center gap-1") {
                     a(
@@ -43,7 +43,7 @@ pub fn index() -> Template<G> {
                     ) { img(src="https://img.shields.io/discord/820400041332179004?label=discord", alt="Discord") }
                 }
                 // endregion
-    
+
                 a(
                     href="/docs/getting_started/installation",
                     class="py-2 px-3 text-white bg-yellow-600 rounded font-medium transition",