chore: declare and check MSRV (#1034)

* chore: declare and check MSRV

* fix: clippy fixes for collapsing if-statements

* ci: add explicit contents read permission to MSRV job

Author: jamadeo

.github/workflows/ci.yml

@@ -205,6 +205,30 @@ jobs:
     - name: Spell Check Repo
       uses: crate-ci/typos@master
 
+  msrv:
+    name: Check MSRV
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - uses: actions/checkout@v7
+
+      - name: Read MSRV from Cargo.toml
+        run: |
+          MSRV=$(cargo metadata --no-deps --format-version 1 \
+            | jq -r '.packages[] | select(.name == "rmcp") | .rust_version')
+          echo "MSRV=$MSRV" >> "$GITHUB_ENV"
+
+      - name: Install MSRV Rust
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.MSRV }}
+
+      - uses: Swatinem/rust-cache@v2
+
+      - name: Check default workspace members with MSRV
+        run: cargo +${{ env.MSRV }} check --all-targets --all-features
+
   test:
     name: Run Tests
     runs-on: ubuntu-latest

Cargo.toml

@@ -9,6 +9,7 @@ rmcp-macros = { version = "3.0.0-beta.1", path = "./crates/rmcp-macros" }
 
 [workspace.package]
 edition = "2024"
+rust-version = "1.88"
 version = "3.0.0-beta.1"
 authors = ["4t145 <u4t145@163.com>"]
 license = "Apache-2.0"

clippy.toml

@@ -1,3 +1,2 @@
-msrv = "1.85"
 too-many-arguments-threshold = 10
 check-private-items = false

crates/rmcp-macros/Cargo.toml

@@ -5,6 +5,7 @@ name = "rmcp-macros"
 license = { workspace = true }
 version = { workspace = true }
 edition = { workspace = true }
+rust-version = { workspace = true }
 repository = { workspace = true }
 homepage = { workspace = true }
 readme = { workspace = true }

crates/rmcp-macros/src/common.rs

@@ -55,17 +55,15 @@ pub fn extract_doc_line(
 /// Returns the full Parameters<T> type if found
 pub fn find_parameters_type_in_sig(sig: &Signature) -> Option<Box<Type>> {
     sig.inputs.iter().find_map(|input| {
-        if let FnArg::Typed(pat_type) = input {
-            if let Type::Path(type_path) = &*pat_type.ty {
-                if type_path
-                    .path
-                    .segments
-                    .last()
-                    .is_some_and(|type_name| type_name.ident == "Parameters")
-                {
-                    return Some(pat_type.ty.clone());
-                }
-            }
+        if let FnArg::Typed(pat_type) = input
+            && let Type::Path(type_path) = &*pat_type.ty
+            && type_path
+                .path
+                .segments
+                .last()
+                .is_some_and(|type_name| type_name.ident == "Parameters")
+        {
+            return Some(pat_type.ty.clone());
         }
         None
     })

crates/rmcp-macros/src/prompt.rs

@@ -132,13 +132,13 @@ pub fn prompt(attr: TokenStream, input: TokenStream) -> syn::Result<TokenStream>
         // 3. make body: { Box::pin(async move { #body }) }
         let new_output = syn::parse2::<ReturnType>({
             let mut lt = quote! { 'static };
-            if let Some(receiver) = fn_item.sig.receiver() {
-                if let Some((_, receiver_lt)) = receiver.reference.as_ref() {
-                    if let Some(receiver_lt) = receiver_lt {
-                        lt = quote! { #receiver_lt };
-                    } else {
-                        lt = quote! { '_ };
-                    }
+            if let Some(receiver) = fn_item.sig.receiver()
+                && let Some((_, receiver_lt)) = receiver.reference.as_ref()
+            {
+                if let Some(receiver_lt) = receiver_lt {
+                    lt = quote! { #receiver_lt };
+                } else {
+                    lt = quote! { '_ };
                 }
             }
             match &fn_item.sig.output {

crates/rmcp-macros/src/tool.rs

@@ -7,16 +7,13 @@ use crate::common::extract_doc_line;
 
 /// Check if a type is Json<T> and extract the inner type T
 fn extract_json_inner_type(ty: &syn::Type) -> Option<&syn::Type> {
-    if let syn::Type::Path(type_path) = ty {
-        if let Some(last_segment) = type_path.path.segments.last() {
-            if last_segment.ident == "Json" {
-                if let syn::PathArguments::AngleBracketed(args) = &last_segment.arguments {
-                    if let Some(syn::GenericArgument::Type(inner_type)) = args.args.first() {
-                        return Some(inner_type);
-                    }
-                }
-            }
-        }
+    if let syn::Type::Path(type_path) = ty
+        && let Some(last_segment) = type_path.path.segments.last()
+        && last_segment.ident == "Json"
+        && let syn::PathArguments::AngleBracketed(args) = &last_segment.arguments
+        && let Some(syn::GenericArgument::Type(inner_type)) = args.args.first()
+    {
+        return Some(inner_type);
     }
     None
 }
@@ -286,13 +283,13 @@ pub fn tool(attr: TokenStream, input: TokenStream) -> syn::Result<TokenStream> {
         let omit_send = cfg!(feature = "local") || attribute.local;
         let new_output = syn::parse2::<ReturnType>({
             let mut lt = quote! { 'static };
-            if let Some(receiver) = fn_item.sig.receiver() {
-                if let Some((_, receiver_lt)) = receiver.reference.as_ref() {
-                    if let Some(receiver_lt) = receiver_lt {
-                        lt = quote! { #receiver_lt };
-                    } else {
-                        lt = quote! { '_ };
-                    }
+            if let Some(receiver) = fn_item.sig.receiver()
+                && let Some((_, receiver_lt)) = receiver.reference.as_ref()
+            {
+                if let Some(receiver_lt) = receiver_lt {
+                    lt = quote! { #receiver_lt };
+                } else {
+                    lt = quote! { '_ };
                 }
             }
             match &fn_item.sig.output {

crates/rmcp/Cargo.toml

@@ -3,6 +3,7 @@ name = "rmcp"
 license = { workspace = true }
 version = { workspace = true }
 edition = { workspace = true }
+rust-version = { workspace = true }
 repository = { workspace = true }
 homepage = { workspace = true }
 readme = { workspace = true }

crates/rmcp/src/handler/server/router/tool.rs

@@ -550,10 +550,10 @@ where
     }
 
     fn notify_if_visible(&self, name: &str) {
-        if self.map.contains_key(name) {
-            if let Some(notifier) = &self.notifier {
-                notifier();
-            }
+        if self.map.contains_key(name)
+            && let Some(notifier) = &self.notifier
+        {
+            notifier();
         }
     }
 

crates/rmcp/src/model/elicitation_schema.rs

@@ -983,17 +983,15 @@ impl EnumSchemaBuilder<MultiSelect> {
                 return Err("One of the provided default values is not in enum values".to_string());
             }
         }
-        if let Some(min) = self.min_items {
-            if (default_values.len() as u64) < min {
-                return Err("Number of provided default values is less than min_items".to_string());
-            }
+        if let Some(min) = self.min_items
+            && (default_values.len() as u64) < min
+        {
+            return Err("Number of provided default values is less than min_items".to_string());
         }
-        if let Some(max) = self.max_items {
-            if (default_values.len() as u64) > max {
-                return Err(
-                    "Number of provided default values is greater than max_items".to_string(),
-                );
-            }
+        if let Some(max) = self.max_items
+            && (default_values.len() as u64) > max
+        {
+            return Err("Number of provided default values is greater than max_items".to_string());
         }
         self.default = default_values;
         Ok(self)