Merge #10902

10902: Handle multiple cargo check quick fix spans r=Veykril a=brandondong

Resolves https://github.com/rust-analyzer/rust-analyzer/issues/10705.

**Cause:**
- For a cargo check diagnostic with multiple spans, only a single quick fix action would be created at the location of `spans[0]`. Additionally, the hover window details would only show the location of `spans[0]` next to the message.

**Fix:**
- Allow cargo check quick fix actions to be triggerable from multiple selection ranges. Specifically, if the selection intersects with any of the replacement spans, the quick fix action is shown.
- No change in behavior for the hover window details. It's pretty minor and I think showing multiple locations next to the message may be more confusing anyways.

Co-authored-by: Brandon <brandondong604@hotmail.com>

14 files changed, 372 insertions, 283 deletions

diff --git a/crates/rust-analyzer/src/diagnostics.rs b/crates/rust-analyzer/src/diagnostics.rs
index 2f63c26ce51..56b3afce98a 100644
--- a/crates/rust-analyzer/src/diagnostics.rs
+++ b/crates/rust-analyzer/src/diagnostics.rs
@@ -29,7 +29,8 @@ pub(crate) struct DiagnosticCollection {
 
 #[derive(Debug, Clone)]
 pub(crate) struct Fix {
-    pub(crate) range: lsp_types::Range,
+    // Fixes may be triggerable from multiple ranges.
+    pub(crate) ranges: Vec<lsp_types::Range>,
     pub(crate) action: lsp_ext::CodeAction,
 }
 
@@ -43,7 +44,7 @@ impl DiagnosticCollection {
         &mut self,
         file_id: FileId,
         diagnostic: lsp_types::Diagnostic,
-        fixes: Vec<lsp_ext::CodeAction>,
+        fix: Option<Fix>,
     ) {
         let diagnostics = self.check.entry(file_id).or_default();
         for existing_diagnostic in diagnostics.iter() {
@@ -53,10 +54,7 @@ impl DiagnosticCollection {
         }
 
         let check_fixes = Arc::make_mut(&mut self.check_fixes);
-        check_fixes
-            .entry(file_id)
-            .or_default()
-            .extend(fixes.into_iter().map(|action| Fix { range: diagnostic.range, action }));
+        check_fixes.entry(file_id).or_default().extend(fix);
         diagnostics.push(diagnostic);
         self.changes.insert(file_id);
     }
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/clippy_pass_by_ref.txt b/crates/rust-analyzer/src/diagnostics/test_data/clippy_pass_by_ref.txt
index fd04163de98..4610984acb9 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/clippy_pass_by_ref.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/clippy_pass_by_ref.txt
@@ -114,7 +114,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -205,7 +205,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -296,55 +296,69 @@
             tags: None,
             data: None,
         },
-        fixes: [
-            CodeAction {
-                title: "consider passing by value instead: `self`",
-                group: None,
-                kind: Some(
-                    CodeActionKind(
-                        "quickfix",
+        fix: Some(
+            Fix {
+                ranges: [
+                    Range {
+                        start: Position {
+                            line: 41,
+                            character: 23,
+                        },
+                        end: Position {
+                            line: 41,
+                            character: 28,
+                        },
+                    },
+                ],
+                action: CodeAction {
+                    title: "consider passing by value instead: `self`",
+                    group: None,
+                    kind: Some(
+                        CodeActionKind(
+                            "quickfix",
+                        ),
                     ),
-                ),
-                edit: Some(
-                    SnippetWorkspaceEdit {
-                        changes: Some(
-                            {
-                                Url {
-                                    scheme: "file",
-                                    cannot_be_a_base: false,
-                                    username: "",
-                                    password: None,
-                                    host: None,
-                                    port: None,
-                                    path: "/test/compiler/mir/tagset.rs",
-                                    query: None,
-                                    fragment: None,
-                                }: [
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 41,
-                                                character: 23,
-                                            },
-                                            end: Position {
-                                                line: 41,
-                                                character: 28,
+                    edit: Some(
+                        SnippetWorkspaceEdit {
+                            changes: Some(
+                                {
+                                    Url {
+                                        scheme: "file",
+                                        cannot_be_a_base: false,
+                                        username: "",
+                                        password: None,
+                                        host: None,
+                                        port: None,
+                                        path: "/test/compiler/mir/tagset.rs",
+                                        query: None,
+                                        fragment: None,
+                                    }: [
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 41,
+                                                    character: 23,
+                                                },
+                                                end: Position {
+                                                    line: 41,
+                                                    character: 28,
+                                                },
                                             },
+                                            new_text: "self",
                                         },
-                                        new_text: "self",
-                                    },
-                                ],
-                            },
-                        ),
-                        document_changes: None,
-                        change_annotations: None,
-                    },
-                ),
-                is_preferred: Some(
-                    true,
-                ),
-                data: None,
+                                    ],
+                                },
+                            ),
+                            document_changes: None,
+                            change_annotations: None,
+                        },
+                    ),
+                    is_preferred: Some(
+                        true,
+                    ),
+                    data: None,
+                },
             },
-        ],
+        ),
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/handles_macro_location.txt b/crates/rust-analyzer/src/diagnostics/test_data/handles_macro_location.txt
index a7f936a703e..989e5cf66d8 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/handles_macro_location.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/handles_macro_location.txt
@@ -59,6 +59,6 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/macro_compiler_error.txt b/crates/rust-analyzer/src/diagnostics/test_data/macro_compiler_error.txt
index 8bee4cfe10a..fe5cf9b3bea 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/macro_compiler_error.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/macro_compiler_error.txt
@@ -64,7 +64,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -131,7 +131,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -224,6 +224,6 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_incompatible_type_for_trait.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_incompatible_type_for_trait.txt
index afc562a0e2b..dc36aa761c0 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_incompatible_type_for_trait.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_incompatible_type_for_trait.txt
@@ -59,6 +59,6 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_mismatched_type.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_mismatched_type.txt
index 05074a914b5..d557196c2bd 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_mismatched_type.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_mismatched_type.txt
@@ -59,6 +59,6 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable.txt
index 3ded70411d3..46d44192c5c 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable.txt
@@ -72,7 +72,7 @@
             ),
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -143,55 +143,69 @@
             tags: None,
             data: None,
         },
-        fixes: [
-            CodeAction {
-                title: "consider prefixing with an underscore: `_foo`",
-                group: None,
-                kind: Some(
-                    CodeActionKind(
-                        "quickfix",
+        fix: Some(
+            Fix {
+                ranges: [
+                    Range {
+                        start: Position {
+                            line: 290,
+                            character: 8,
+                        },
+                        end: Position {
+                            line: 290,
+                            character: 11,
+                        },
+                    },
+                ],
+                action: CodeAction {
+                    title: "consider prefixing with an underscore: `_foo`",
+                    group: None,
+                    kind: Some(
+                        CodeActionKind(
+                            "quickfix",
+                        ),
                     ),
-                ),
-                edit: Some(
-                    SnippetWorkspaceEdit {
-                        changes: Some(
-                            {
-                                Url {
-                                    scheme: "file",
-                                    cannot_be_a_base: false,
-                                    username: "",
-                                    password: None,
-                                    host: None,
-                                    port: None,
-                                    path: "/test/driver/subcommand/repl.rs",
-                                    query: None,
-                                    fragment: None,
-                                }: [
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 290,
-                                                character: 8,
-                                            },
-                                            end: Position {
-                                                line: 290,
-                                                character: 11,
+                    edit: Some(
+                        SnippetWorkspaceEdit {
+                            changes: Some(
+                                {
+                                    Url {
+                                        scheme: "file",
+                                        cannot_be_a_base: false,
+                                        username: "",
+                                        password: None,
+                                        host: None,
+                                        port: None,
+                                        path: "/test/driver/subcommand/repl.rs",
+                                        query: None,
+                                        fragment: None,
+                                    }: [
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 290,
+                                                    character: 8,
+                                                },
+                                                end: Position {
+                                                    line: 290,
+                                                    character: 11,
+                                                },
                                             },
+                                            new_text: "_foo",
                                         },
-                                        new_text: "_foo",
-                                    },
-                                ],
-                            },
-                        ),
-                        document_changes: None,
-                        change_annotations: None,
-                    },
-                ),
-                is_preferred: Some(
-                    true,
-                ),
-                data: None,
+                                    ],
+                                },
+                            ),
+                            document_changes: None,
+                            change_annotations: None,
+                        },
+                    ),
+                    is_preferred: Some(
+                        true,
+                    ),
+                    data: None,
+                },
             },
-        ],
+        ),
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_hint.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_hint.txt
index 0993aa1af14..b595487e8f3 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_hint.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_hint.txt
@@ -72,7 +72,7 @@
             ),
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -143,55 +143,69 @@
             tags: None,
             data: None,
         },
-        fixes: [
-            CodeAction {
-                title: "consider prefixing with an underscore: `_foo`",
-                group: None,
-                kind: Some(
-                    CodeActionKind(
-                        "quickfix",
+        fix: Some(
+            Fix {
+                ranges: [
+                    Range {
+                        start: Position {
+                            line: 290,
+                            character: 8,
+                        },
+                        end: Position {
+                            line: 290,
+                            character: 11,
+                        },
+                    },
+                ],
+                action: CodeAction {
+                    title: "consider prefixing with an underscore: `_foo`",
+                    group: None,
+                    kind: Some(
+                        CodeActionKind(
+                            "quickfix",
+                        ),
                     ),
-                ),
-                edit: Some(
-                    SnippetWorkspaceEdit {
-                        changes: Some(
-                            {
-                                Url {
-                                    scheme: "file",
-                                    cannot_be_a_base: false,
-                                    username: "",
-                                    password: None,
-                                    host: None,
-                                    port: None,
-                                    path: "/test/driver/subcommand/repl.rs",
-                                    query: None,
-                                    fragment: None,
-                                }: [
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 290,
-                                                character: 8,
-                                            },
-                                            end: Position {
-                                                line: 290,
-                                                character: 11,
+                    edit: Some(
+                        SnippetWorkspaceEdit {
+                            changes: Some(
+                                {
+                                    Url {
+                                        scheme: "file",
+                                        cannot_be_a_base: false,
+                                        username: "",
+                                        password: None,
+                                        host: None,
+                                        port: None,
+                                        path: "/test/driver/subcommand/repl.rs",
+                                        query: None,
+                                        fragment: None,
+                                    }: [
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 290,
+                                                    character: 8,
+                                                },
+                                                end: Position {
+                                                    line: 290,
+                                                    character: 11,
+                                                },
                                             },
+                                            new_text: "_foo",
                                         },
-                                        new_text: "_foo",
-                                    },
-                                ],
-                            },
-                        ),
-                        document_changes: None,
-                        change_annotations: None,
-                    },
-                ),
-                is_preferred: Some(
-                    true,
-                ),
-                data: None,
+                                    ],
+                                },
+                            ),
+                            document_changes: None,
+                            change_annotations: None,
+                        },
+                    ),
+                    is_preferred: Some(
+                        true,
+                    ),
+                    data: None,
+                },
             },
-        ],
+        ),
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_info.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_info.txt
index d7a974ae579..3ee50392a7f 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_info.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_unused_variable_as_info.txt
@@ -72,7 +72,7 @@
             ),
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -143,55 +143,69 @@
             tags: None,
             data: None,
         },
-        fixes: [
-            CodeAction {
-                title: "consider prefixing with an underscore: `_foo`",
-                group: None,
-                kind: Some(
-                    CodeActionKind(
-                        "quickfix",
+        fix: Some(
+            Fix {
+                ranges: [
+                    Range {
+                        start: Position {
+                            line: 290,
+                            character: 8,
+                        },
+                        end: Position {
+                            line: 290,
+                            character: 11,
+                        },
+                    },
+                ],
+                action: CodeAction {
+                    title: "consider prefixing with an underscore: `_foo`",
+                    group: None,
+                    kind: Some(
+                        CodeActionKind(
+                            "quickfix",
+                        ),
                     ),
-                ),
-                edit: Some(
-                    SnippetWorkspaceEdit {
-                        changes: Some(
-                            {
-                                Url {
-                                    scheme: "file",
-                                    cannot_be_a_base: false,
-                                    username: "",
-                                    password: None,
-                                    host: None,
-                                    port: None,
-                                    path: "/test/driver/subcommand/repl.rs",
-                                    query: None,
-                                    fragment: None,
-                                }: [
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 290,
-                                                character: 8,
-                                            },
-                                            end: Position {
-                                                line: 290,
-                                                character: 11,
+                    edit: Some(
+                        SnippetWorkspaceEdit {
+                            changes: Some(
+                                {
+                                    Url {
+                                        scheme: "file",
+                                        cannot_be_a_base: false,
+                                        username: "",
+                                        password: None,
+                                        host: None,
+                                        port: None,
+                                        path: "/test/driver/subcommand/repl.rs",
+                                        query: None,
+                                        fragment: None,
+                                    }: [
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 290,
+                                                    character: 8,
+                                                },
+                                                end: Position {
+                                                    line: 290,
+                                                    character: 11,
+                                                },
                                             },
+                                            new_text: "_foo",
                                         },
-                                        new_text: "_foo",
-                                    },
-                                ],
-                            },
-                        ),
-                        document_changes: None,
-                        change_annotations: None,
-                    },
-                ),
-                is_preferred: Some(
-                    true,
-                ),
-                data: None,
+                                    ],
+                                },
+                            ),
+                            document_changes: None,
+                            change_annotations: None,
+                        },
+                    ),
+                    is_preferred: Some(
+                        true,
+                    ),
+                    data: None,
+                },
             },
-        ],
+        ),
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/rustc_wrong_number_of_parameters.txt b/crates/rust-analyzer/src/diagnostics/test_data/rustc_wrong_number_of_parameters.txt
index 5ea27a15275..8ec92888ce1 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/rustc_wrong_number_of_parameters.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/rustc_wrong_number_of_parameters.txt
@@ -88,7 +88,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -179,6 +179,6 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/test_data/snap_multi_line_fix.txt b/crates/rust-analyzer/src/diagnostics/test_data/snap_multi_line_fix.txt
index f77abde5155..d7987f65eda 100644
--- a/crates/rust-analyzer/src/diagnostics/test_data/snap_multi_line_fix.txt
+++ b/crates/rust-analyzer/src/diagnostics/test_data/snap_multi_line_fix.txt
@@ -114,7 +114,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -205,7 +205,7 @@
             tags: None,
             data: None,
         },
-        fixes: [],
+        fix: None,
     },
     MappedRustDiagnostic {
         url: Url {
@@ -296,68 +296,92 @@
             tags: None,
             data: None,
         },
-        fixes: [
-            CodeAction {
-                title: "return the expression directly: `(0..10).collect()`",
-                group: None,
-                kind: Some(
-                    CodeActionKind(
-                        "quickfix",
+        fix: Some(
+            Fix {
+                ranges: [
+                    Range {
+                        start: Position {
+                            line: 2,
+                            character: 4,
+                        },
+                        end: Position {
+                            line: 2,
+                            character: 30,
+                        },
+                    },
+                    Range {
+                        start: Position {
+                            line: 3,
+                            character: 4,
+                        },
+                        end: Position {
+                            line: 3,
+                            character: 5,
+                        },
+                    },
+                ],
+                action: CodeAction {
+                    title: "return the expression directly: `(0..10).collect()`",
+                    group: None,
+                    kind: Some(
+                        CodeActionKind(
+                            "quickfix",
+                        ),
                     ),
-                ),
-                edit: Some(
-                    SnippetWorkspaceEdit {
-                        changes: Some(
-                            {
-                                Url {
-                                    scheme: "file",
-                                    cannot_be_a_base: false,
-                                    username: "",
-                                    password: None,
-                                    host: None,
-                                    port: None,
-                                    path: "/test/src/main.rs",
-                                    query: None,
-                                    fragment: None,
-                                }: [
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 2,
-                                                character: 4,
-                                            },
-                                            end: Position {
-                                                line: 2,
-                                                character: 30,
+                    edit: Some(
+                        SnippetWorkspaceEdit {
+                            changes: Some(
+                                {
+                                    Url {
+                                        scheme: "file",
+                                        cannot_be_a_base: false,
+                                        username: "",
+                                        password: None,
+                                        host: None,
+                                        port: None,
+                                        path: "/test/src/main.rs",
+                                        query: None,
+                                        fragment: None,
+                                    }: [
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 2,
+                                                    character: 4,
+                                                },
+                                                end: Position {
+                                                    line: 2,
+                                                    character: 30,
+                                                },
                                             },
+                                            new_text: "",
                                         },
-                                        new_text: "",
-                                    },
-                                    TextEdit {
-                                        range: Range {
-                                            start: Position {
-                                                line: 3,
-                                                character: 4,
-                                            },
-                                            end: Position {
-                                                line: 3,
-                                                character: 5,
+                                        TextEdit {
+                                            range: Range {
+                                                start: Position {
+                                                    line: 3,
+                                                    character: 4,
+                                                },
+                                                end: Position {
+                                                    line: 3,
+                                                    character: 5,
+                                                },
                                             },
+                                            new_text: "(0..10).collect()",
                                         },
-                                        new_text: "(0..10).collect()",
-                                    },
-                                ],
-                            },
-                        ),
-                        document_changes: None,
-                        change_annotations: None,
-                    },
-                ),
-                is_preferred: Some(
-                    true,
-                ),
-                data: None,
+                                    ],
+                                },
+                            ),
+                            document_changes: None,
+                            change_annotations: None,
+                        },
+                    ),
+                    is_preferred: Some(
+                        true,
+                    ),
+                    data: None,
+                },
             },
-        ],
+        ),
     },
 ]
diff --git a/crates/rust-analyzer/src/diagnostics/to_proto.rs b/crates/rust-analyzer/src/diagnostics/to_proto.rs
index bdc56b31962..5f936ee0865 100644
--- a/crates/rust-analyzer/src/diagnostics/to_proto.rs
+++ b/crates/rust-analyzer/src/diagnostics/to_proto.rs
@@ -9,7 +9,7 @@ use vfs::{AbsPath, AbsPathBuf};
 
 use crate::{lsp_ext, to_proto::url_from_abs_path};
 
-use super::DiagnosticsMapConfig;
+use super::{DiagnosticsMapConfig, Fix};
 
 /// Determines the LSP severity from a diagnostic
 fn diagnostic_severity(
@@ -124,7 +124,7 @@ fn resolve_path(
 
 struct SubDiagnostic {
     related: lsp_types::DiagnosticRelatedInformation,
-    suggested_fix: Option<lsp_ext::CodeAction>,
+    suggested_fix: Option<Fix>,
 }
 
 enum MappedRustChildDiagnostic {
@@ -181,18 +181,24 @@ fn map_rust_child_diagnostic(
                 location: location(config, workspace_root, spans[0]),
                 message: message.clone(),
             },
-            suggested_fix: Some(lsp_ext::CodeAction {
-                title: message,
-                group: None,
-                kind: Some(lsp_types::CodeActionKind::QUICKFIX),
-                edit: Some(lsp_ext::SnippetWorkspaceEdit {
-                    // FIXME: there's no good reason to use edit_map here....
-                    changes: Some(edit_map),
-                    document_changes: None,
-                    change_annotations: None,
-                }),
-                is_preferred: Some(true),
-                data: None,
+            suggested_fix: Some(Fix {
+                ranges: spans
+                    .iter()
+                    .map(|&span| location(config, workspace_root, span).range)
+                    .collect(),
+                action: lsp_ext::CodeAction {
+                    title: message,
+                    group: None,
+                    kind: Some(lsp_types::CodeActionKind::QUICKFIX),
+                    edit: Some(lsp_ext::SnippetWorkspaceEdit {
+                        // FIXME: there's no good reason to use edit_map here....
+                        changes: Some(edit_map),
+                        document_changes: None,
+                        change_annotations: None,
+                    }),
+                    is_preferred: Some(true),
+                    data: None,
+                },
             }),
         })
     }
@@ -202,7 +208,7 @@ fn map_rust_child_diagnostic(
 pub(crate) struct MappedRustDiagnostic {
     pub(crate) url: lsp_types::Url,
     pub(crate) diagnostic: lsp_types::Diagnostic,
-    pub(crate) fixes: Vec<lsp_ext::CodeAction>,
+    pub(crate) fix: Option<Fix>,
 }
 
 /// Converts a Rust root diagnostic to LSP form
@@ -359,7 +365,7 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
                 diagnostics.push(MappedRustDiagnostic {
                     url: secondary_location.uri,
                     diagnostic,
-                    fixes: Vec::new(),
+                    fix: None,
                 });
             }
 
@@ -388,7 +394,7 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
                     tags: if tags.is_empty() { None } else { Some(tags.clone()) },
                     data: None,
                 },
-                fixes: Vec::new(),
+                fix: None,
             });
 
             // Emit hint-level diagnostics for all `related_information` entries such as "help"s.
@@ -405,7 +411,7 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
                 }
                 diagnostics.push(MappedRustDiagnostic {
                     url: sub.related.location.uri.clone(),
-                    fixes: sub.suggested_fix.iter().cloned().collect(),
+                    fix: sub.suggested_fix.clone(),
                     diagnostic: lsp_types::Diagnostic {
                         range: sub.related.location.range,
                         severity: Some(lsp_types::DiagnosticSeverity::HINT),
diff --git a/crates/rust-analyzer/src/handlers.rs b/crates/rust-analyzer/src/handlers.rs
index 0ddddeca675..bf153012d94 100644
--- a/crates/rust-analyzer/src/handlers.rs
+++ b/crates/rust-analyzer/src/handlers.rs
@@ -1081,8 +1081,13 @@ pub(crate) fn handle_code_action(
     for fix in snap.check_fixes.get(&frange.file_id).into_iter().flatten() {
         // FIXME: this mapping is awkward and shouldn't exist. Refactor
         // `snap.check_fixes` to not convert to LSP prematurely.
-        let fix_range = from_proto::text_range(&line_index, fix.range);
-        if fix_range.intersect(frange.range).is_some() {
+        let intersect_fix_range = fix
+            .ranges
+            .iter()
+            .copied()
+            .map(|range| from_proto::text_range(&line_index, range))
+            .any(|fix_range| fix_range.intersect(frange.range).is_some());
+        if intersect_fix_range {
             res.push(fix.action.clone());
         }
     }
diff --git a/crates/rust-analyzer/src/main_loop.rs b/crates/rust-analyzer/src/main_loop.rs
index 979b3b15221..2d83cbee669 100644
--- a/crates/rust-analyzer/src/main_loop.rs
+++ b/crates/rust-analyzer/src/main_loop.rs
@@ -370,7 +370,7 @@ impl GlobalState {
                                     Ok(file_id) => self.diagnostics.add_check_diagnostic(
                                         file_id,
                                         diag.diagnostic,
-                                        diag.fixes,
+                                        diag.fix,
                                     ),
                                     Err(err) => {
                                         tracing::error!(