Declutter statements

Cargo.toml

@@ -37,6 +37,7 @@ inefficient_to_string = "warn"
 linkedlist = "warn"
 lossy_float_literal = "warn"
 macro_use_imports = "warn"
+manual_assert = "warn"
 manual_let_else = "warn"
 match_same_arms = "warn"
 match_wildcard_for_single_variants = "warn"

axum-extra/src/routing/mod.rs

@@ -30,12 +30,12 @@ pub use self::typed::{SecondElementIs, TypedPath};
 #[doc(hidden)]
 #[must_use]
 pub const fn __private_validate_static_path(path: &'static str) -> &'static str {
-    if path.is_empty() {
-        panic!("Paths must start with a `/`. Use \"/\" for root routes")
-    }
-    if path.as_bytes()[0] != b'/' {
-        panic!("Paths must start with /");
-    }
+    assert!(
+        !path.is_empty(),
+        "Paths must start with a `/`. Use \"/\" for root routes"
+    );
+    // `assert_eq!` is not allowed in constant functions so we have to do it manually.
+    assert!(path.as_bytes()[0] == b'/', "Paths must start with /");
     path
 }
 
@@ -356,9 +356,10 @@ where
 
 #[track_caller]
 fn validate_tsr_path(path: &str) {
-    if path == "/" {
-        panic!("Cannot add a trailing slash redirect route for `/`")
-    }
+    assert!(
+        path != "/",
+        "Cannot add a trailing slash redirect route for `/`"
+    );
 }
 
 fn add_tsr_redirect_route<S>(router: Router<S>, path: &str) -> Router<S>

axum/benches/benches.rs

@@ -230,9 +230,7 @@ fn install_rewrk() {
     let status = cmd
         .status()
         .unwrap_or_else(|_| panic!("failed to install rewrk"));
-    if !status.success() {
-        panic!("failed to install rewrk");
-    }
+    assert!(status.success(), "failed to install rewrk");
 }
 
 fn ensure_rewrk_is_installed() {

axum/src/response/sse.rs

@@ -203,9 +203,10 @@ impl Event {
     where
         T: AsRef<str>,
     {
-        if self.flags.contains(EventFlags::HAS_DATA) {
-            panic!("Called `Event::data` multiple times");
-        }
+        assert!(
+            !self.flags.contains(EventFlags::HAS_DATA),
+            "Called `Event::data` multiple times"
+        );
 
         for line in memchr_split(b'\n', data.as_ref().as_bytes()) {
             self.field("data", line);
@@ -246,9 +247,10 @@ impl Event {
                 self.0.flush()
             }
         }
-        if self.flags.contains(EventFlags::HAS_DATA) {
-            panic!("Called `Event::json_data` multiple times");
-        }
+        assert!(
+            !self.flags.contains(EventFlags::HAS_DATA),
+            "Called `Event::json_data` multiple times"
+        );
 
         let buffer = self.buffer.as_mut();
         buffer.extend_from_slice(b"data: ");
@@ -297,9 +299,10 @@ impl Event {
     where
         T: AsRef<str>,
     {
-        if self.flags.contains(EventFlags::HAS_EVENT) {
-            panic!("Called `Event::event` multiple times");
-        }
+        assert!(
+            !self.flags.contains(EventFlags::HAS_EVENT),
+            "Called `Event::event` multiple times"
+        );
         self.flags.insert(EventFlags::HAS_EVENT);
 
         self.field("event", event.as_ref());
@@ -317,9 +320,10 @@ impl Event {
     ///
     /// Panics if this function has already been called on this event.
     pub fn retry(mut self, duration: Duration) -> Self {
-        if self.flags.contains(EventFlags::HAS_RETRY) {
-            panic!("Called `Event::retry` multiple times");
-        }
+        assert!(
+            !self.flags.contains(EventFlags::HAS_RETRY),
+            "Called `Event::retry` multiple times"
+        );
         self.flags.insert(EventFlags::HAS_RETRY);
 
         let buffer = self.buffer.as_mut();
@@ -364,9 +368,10 @@ impl Event {
     where
         T: AsRef<str>,
     {
-        if self.flags.contains(EventFlags::HAS_ID) {
-            panic!("Called `Event::id` multiple times");
-        }
+        assert!(
+            !self.flags.contains(EventFlags::HAS_ID),
+            "Called `Event::id` multiple times"
+        );
         self.flags.insert(EventFlags::HAS_ID);
 
         let id = id.as_ref().as_bytes();

axum/src/routing/method_routing.rs

@@ -835,12 +835,11 @@ where
             S: Clone,
         {
             if endpoint_filter.contains(filter) {
-                if out.is_some() {
-                    panic!(
-                        "Overlapping method route. Cannot add two method routes that both handle \
+                assert!(
+                    !out.is_some(),
+                    "Overlapping method route. Cannot add two method routes that both handle \
                          `{method_name}`",
-                    )
-                }
+                );
                 *out = endpoint.clone();
                 for method in methods {
                     append_allow_header(allow_header, method);

axum/src/routing/mod.rs

@@ -203,9 +203,10 @@ where
     #[doc(alias = "scope")] // Some web frameworks like actix-web use this term
     #[track_caller]
     pub fn nest(self, path: &str, router: Self) -> Self {
-        if path.is_empty() || path == "/" {
-            panic!("Nesting at the root is no longer supported. Use merge instead.");
-        }
+        assert!(
+            !(path.is_empty() || path == "/"),
+            "Nesting at the root is no longer supported. Use merge instead."
+        );
 
         let RouterInner {
             path_router,
@@ -229,9 +230,10 @@ where
         T::Response: IntoResponse,
         T::Future: Send + 'static,
     {
-        if path.is_empty() || path == "/" {
-            panic!("Nesting at the root is no longer supported. Use fallback_service instead.");
-        }
+        assert!(
+            !(path.is_empty() || path == "/"),
+            "Nesting at the root is no longer supported. Use fallback_service instead."
+        );
 
         tap_inner!(self, mut this => {
             panic_on_err!(this.path_router.nest_service(path, service));

axum/src/routing/path_router.rs

@@ -282,12 +282,11 @@ where
         <L::Service as Service<Request>>::Error: Into<Infallible> + 'static,
         <L::Service as Service<Request>>::Future: Send + 'static,
     {
-        if self.routes.is_empty() {
-            panic!(
-                "Adding a route_layer before any routes is a no-op. \
+        assert!(
+            !self.routes.is_empty(),
+            "Adding a route_layer before any routes is a no-op. \
                  Add the routes you want the layer to apply to first."
-            );
-        }
+        );
 
         let routes = self
             .routes