Add multiple generate for enum generate is, as, try_into

A4-Tacks · A4-Tacks · commit 9bf3695a0dd0 · 2025-11-22T22:03:50.000+08:00
Examples
---
```rust
enum Variant {
    Undefined,
    $0Minor,
    M$0ajor,
}
```
-&gt;
```rust
enum Variant {
    Undefined,
    Minor,
    Major,
}

impl Variant {
    /// Returns `true` if the variant is [`Minor`].
    ///
    /// [`Minor`]: Variant::Minor
    #[must_use]
    fn is_minor(&amp;self) -&gt; bool {
        matches!(self, Self::Minor)
    }

    /// Returns `true` if the variant is [`Major`].
    ///
    /// [`Major`]: Variant::Major
    #[must_use]
    fn is_major(&amp;self) -&gt; bool {
        matches!(self, Self::Major)
    }
}
```

---

```rust
enum Value {
    Unit(()),
    $0Number(i32),
    Text(String)$0,
}
```
-&gt;
```rust
enum Value {
    Unit(()),
    Number(i32),
    Text(String),
}

impl Value {
    fn try_into_number(self) -&gt; Result&lt;i32, Self&gt; {
        if let Self::Number(v) = self {
            Ok(v)
        } else {
            Err(self)
        }
    }

    fn try_into_text(self) -&gt; Result&lt;String, Self&gt; {
        if let Self::Text(v) = self {
            Ok(v)
        } else {
            Err(self)
        }
    }
}
```

---

```rust
enum Value {
    Unit(()),
    $0Number(i32),
    Text(String)$0,
}
```
-&gt;
```rust
enum Value {
    Unit(()),
    Number(i32),
    Text(String),
}

impl Value {
    fn as_number(&amp;self) -&gt; Option&lt;&amp;i32&gt; {
        if let Self::Number(v) = self {
            Some(v)
        } else {
            None
        }
    }

    fn as_text(&amp;self) -&gt; Option&lt;&amp;String&gt; {
        if let Self::Text(v) = self {
            Some(v)
        } else {
            None
        }
    }
}
```
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_is_method.rs
@@ -1,13 +1,12 @@
-use std::slice;
-
 use ide_db::assists::GroupLabel;
+use itertools::Itertools;
 use stdx::to_lower_snake_case;
 use syntax::ast::HasVisibility;
 use syntax::ast::{self, AstNode, HasName};
 
 use crate::{
     AssistContext, AssistId, Assists,
-    utils::{add_method_to_adt, find_struct_impl},
+    utils::{add_method_to_adt, find_struct_impl, is_selected},
 };
 
 // Assist: generate_enum_is_method
@@ -41,20 +40,21 @@ use crate::{
 // ```
 pub(crate) fn generate_enum_is_method(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> {
     let variant = ctx.find_node_at_offset::<ast::Variant>()?;
-    let variant_name = variant.name()?;
     let parent_enum = ast::Adt::Enum(variant.parent_enum());
-    let pattern_suffix = match variant.kind() {
-        ast::StructKind::Record(_) => " { .. }",
-        ast::StructKind::Tuple(_) => "(..)",
-        ast::StructKind::Unit => "",
-    };
-
+    let variants = variant
+        .parent_enum()
+        .variant_list()?
+        .variants()
+        .filter(|it| is_selected(it, ctx.selection_trimmed(), true))
+        .collect::<Vec<_>>();
+    let methods = variants.iter().map(Method::new).collect::<Option<Vec<_>>>()?;
     let enum_name = parent_enum.name()?;
     let enum_lowercase_name = to_lower_snake_case(&enum_name.to_string()).replace('_', " ");
-    let fn_name = format!("is_{}", &to_lower_snake_case(&variant_name.text()));
+    let fn_names = methods.iter().map(|it| it.fn_name.clone()).collect::<Vec<_>>();
+    stdx::never!(variants.is_empty());
 
     // Return early if we've found an existing new fn
-    let impl_def = find_struct_impl(ctx, &parent_enum, slice::from_ref(&fn_name))?;
+    let impl_def = find_struct_impl(ctx, &parent_enum, &fn_names)?;
 
     let target = variant.syntax().text_range();
     acc.add_group(
@@ -64,21 +64,47 @@ pub(crate) fn generate_enum_is_method(acc: &mut Assists, ctx: &AssistContext<'_>
         target,
         |builder| {
             let vis = parent_enum.visibility().map_or(String::new(), |v| format!("{v} "));
-            let method = format!(
-                "    /// Returns `true` if the {enum_lowercase_name} is [`{variant_name}`].
+            let method = methods
+                .iter()
+                .map(|Method { pattern_suffix, fn_name, variant_name }| {
+                    format!(
+                        "    \
+    /// Returns `true` if the {enum_lowercase_name} is [`{variant_name}`].
     ///
     /// [`{variant_name}`]: {enum_name}::{variant_name}
     #[must_use]
     {vis}fn {fn_name}(&self) -> bool {{
         matches!(self, Self::{variant_name}{pattern_suffix})
     }}",
-            );
+                    )
+                })
+                .join("\n\n");
 
             add_method_to_adt(builder, &parent_enum, impl_def, &method);
         },
     )
 }
 
+struct Method {
+    pattern_suffix: &'static str,
+    fn_name: String,
+    variant_name: ast::Name,
+}
+
+impl Method {
+    fn new(variant: &ast::Variant) -> Option<Self> {
+        let pattern_suffix = match variant.kind() {
+            ast::StructKind::Record(_) => " { .. }",
+            ast::StructKind::Tuple(_) => "(..)",
+            ast::StructKind::Unit => "",
+        };
+
+        let variant_name = variant.name()?;
+        let fn_name = format!("is_{}", &to_lower_snake_case(&variant_name.text()));
+        Some(Method { pattern_suffix, fn_name, variant_name })
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use crate::tests::{check_assist, check_assist_not_applicable};
@@ -113,6 +139,42 @@ impl Variant {
         );
     }
 
+    #[test]
+    fn test_generate_enum_is_from_multiple_variant() {
+        check_assist(
+            generate_enum_is_method,
+            r#"
+enum Variant {
+    Undefined,
+    $0Minor,
+    M$0ajor,
+}"#,
+            r#"enum Variant {
+    Undefined,
+    Minor,
+    Major,
+}
+
+impl Variant {
+    /// Returns `true` if the variant is [`Minor`].
+    ///
+    /// [`Minor`]: Variant::Minor
+    #[must_use]
+    fn is_minor(&self) -> bool {
+        matches!(self, Self::Minor)
+    }
+
+    /// Returns `true` if the variant is [`Major`].
+    ///
+    /// [`Major`]: Variant::Major
+    #[must_use]
+    fn is_major(&self) -> bool {
+        matches!(self, Self::Major)
+    }
+}"#,
+        );
+    }
+
     #[test]
     fn test_generate_enum_is_already_implemented() {
         check_assist_not_applicable(
diff --git a/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs b/src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_enum_projection_method.rs
@@ -1,5 +1,3 @@
-use std::slice;
-
 use ide_db::assists::GroupLabel;
 use itertools::Itertools;
 use stdx::to_lower_snake_case;
@@ -8,7 +6,7 @@ use syntax::ast::{self, AstNode, HasName};
 
 use crate::{
     AssistContext, AssistId, Assists,
-    utils::{add_method_to_adt, find_struct_impl},
+    utils::{add_method_to_adt, find_struct_impl, is_selected},
 };
 
 // Assist: generate_enum_try_into_method
@@ -128,29 +126,22 @@ fn generate_enum_projection_method(
     } = props;
 
     let variant = ctx.find_node_at_offset::<ast::Variant>()?;
-    let variant_name = variant.name()?;
     let parent_enum = ast::Adt::Enum(variant.parent_enum());
-
-    let (pattern_suffix, field_type, bound_name) = match variant.kind() {
-        ast::StructKind::Record(record) => {
-            let (field,) = record.fields().collect_tuple()?;
-            let name = field.name()?.to_string();
-            let ty = field.ty()?;
-            let pattern_suffix = format!(" {{ {name} }}");
-            (pattern_suffix, ty, name)
-        }
-        ast::StructKind::Tuple(tuple) => {
-            let (field,) = tuple.fields().collect_tuple()?;
-            let ty = field.ty()?;
-            ("(v)".to_owned(), ty, "v".to_owned())
-        }
-        ast::StructKind::Unit => return None,
-    };
-
-    let fn_name = format!("{fn_name_prefix}_{}", &to_lower_snake_case(&variant_name.text()));
+    let variants = variant
+        .parent_enum()
+        .variant_list()?
+        .variants()
+        .filter(|it| is_selected(it, ctx.selection_trimmed(), true))
+        .collect::<Vec<_>>();
+    let methods = variants
+        .iter()
+        .map(|variant| Method::new(variant, fn_name_prefix))
+        .collect::<Option<Vec<_>>>()?;
+    let fn_names = methods.iter().map(|it| it.fn_name.clone()).collect::<Vec<_>>();
+    stdx::never!(variants.is_empty());
 
     // Return early if we've found an existing new fn
-    let impl_def = find_struct_impl(ctx, &parent_enum, slice::from_ref(&fn_name))?;
+    let impl_def = find_struct_impl(ctx, &parent_enum, &fn_names)?;
 
     let target = variant.syntax().text_range();
     acc.add_group(
@@ -161,29 +152,66 @@ fn generate_enum_projection_method(
         |builder| {
             let vis = parent_enum.visibility().map_or(String::new(), |v| format!("{v} "));
 
-            let field_type_syntax = field_type.syntax();
+            let must_use = if ctx.config.assist_emit_must_use { "#[must_use]\n    " } else { "" };
 
-            let must_use = if ctx.config.assist_emit_must_use {
-                "#[must_use]\n    "
-            } else {
-                ""
-            };
-
-            let method = format!(
-                "    {must_use}{vis}fn {fn_name}({self_param}) -> {return_prefix}{field_type_syntax}{return_suffix} {{
+            let method = methods
+                .iter()
+                .map(|Method { pattern_suffix, field_type, bound_name, fn_name, variant_name }| {
+                    format!(
+                        "    \
+    {must_use}{vis}fn {fn_name}({self_param}) -> {return_prefix}{field_type}{return_suffix} {{
         if let Self::{variant_name}{pattern_suffix} = self {{
             {happy_case}({bound_name})
         }} else {{
             {sad_case}
         }}
     }}"
-            );
+                    )
+                })
+                .join("\n\n");
 
             add_method_to_adt(builder, &parent_enum, impl_def, &method);
         },
     )
 }
 
+struct Method {
+    pattern_suffix: String,
+    field_type: ast::Type,
+    bound_name: String,
+    fn_name: String,
+    variant_name: ast::Name,
+}
+
+impl Method {
+    fn new(variant: &ast::Variant, fn_name_prefix: &str) -> Option<Self> {
+        let variant_name = variant.name()?;
+        let fn_name = format!("{fn_name_prefix}_{}", &to_lower_snake_case(&variant_name.text()));
+
+        match variant.kind() {
+            ast::StructKind::Record(record) => {
+                let (field,) = record.fields().collect_tuple()?;
+                let name = field.name()?.to_string();
+                let field_type = field.ty()?;
+                let pattern_suffix = format!(" {{ {name} }}");
+                Some(Method { pattern_suffix, field_type, bound_name: name, fn_name, variant_name })
+            }
+            ast::StructKind::Tuple(tuple) => {
+                let (field,) = tuple.fields().collect_tuple()?;
+                let field_type = field.ty()?;
+                Some(Method {
+                    pattern_suffix: "(v)".to_owned(),
+                    field_type,
+                    bound_name: "v".to_owned(),
+                    variant_name,
+                    fn_name,
+                })
+            }
+            ast::StructKind::Unit => None,
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use crate::tests::{check_assist, check_assist_not_applicable};
@@ -216,6 +244,42 @@ impl Value {
         );
     }
 
+    #[test]
+    fn test_generate_enum_multiple_try_into_tuple_variant() {
+        check_assist(
+            generate_enum_try_into_method,
+            r#"
+enum Value {
+    Unit(()),
+    $0Number(i32),
+    Text(String)$0,
+}"#,
+            r#"enum Value {
+    Unit(()),
+    Number(i32),
+    Text(String),
+}
+
+impl Value {
+    fn try_into_number(self) -> Result<i32, Self> {
+        if let Self::Number(v) = self {
+            Ok(v)
+        } else {
+            Err(self)
+        }
+    }
+
+    fn try_into_text(self) -> Result<String, Self> {
+        if let Self::Text(v) = self {
+            Ok(v)
+        } else {
+            Err(self)
+        }
+    }
+}"#,
+        );
+    }
+
     #[test]
     fn test_generate_enum_try_into_already_implemented() {
         check_assist_not_applicable(
@@ -323,6 +387,42 @@ impl Value {
         );
     }
 
+    #[test]
+    fn test_generate_enum_as_multiple_tuple_variant() {
+        check_assist(
+            generate_enum_as_method,
+            r#"
+enum Value {
+    Unit(()),
+    $0Number(i32),
+    Text(String)$0,
+}"#,
+            r#"enum Value {
+    Unit(()),
+    Number(i32),
+    Text(String),
+}
+
+impl Value {
+    fn as_number(&self) -> Option<&i32> {
+        if let Self::Number(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+
+    fn as_text(&self) -> Option<&String> {
+        if let Self::Text(v) = self {
+            Some(v)
+        } else {
+            None
+        }
+    }
+}"#,
+        );
+    }
+
     #[test]
     fn test_generate_enum_as_record_variant() {
         check_assist(
