fix(lsp): apply import fix to missing declaration code action (#23924)

7 files changed, 185 insertions, 3 deletions

diff --git a/cli/jsr.rs b/cli/jsr.rs
index c4cb87dbd..bdfba7f10 100644
--- a/cli/jsr.rs
+++ b/cli/jsr.rs
@@ -111,12 +111,32 @@ impl JsrCacheResolver {
   ) -> Option<String> {
     let info = self.package_version_info(nv)?;
     let path = path.strip_prefix("./").unwrap_or(path);
+    let mut sloppy_fallback = None;
     for (export, path_) in info.exports() {
-      if path_.strip_prefix("./").unwrap_or(path_) == path {
+      let path_ = path_.strip_prefix("./").unwrap_or(path_);
+      if path_ == path {
         return Some(export.strip_prefix("./").unwrap_or(export).to_string());
       }
+      // TSC in some cases will suggest a `.js` import path for a `.d.ts` source
+      // file.
+      if sloppy_fallback.is_none() {
+        let path = path
+          .strip_suffix(".js")
+          .or_else(|| path.strip_suffix(".mjs"))
+          .or_else(|| path.strip_suffix(".cjs"))
+          .unwrap_or(path);
+        let path_ = path_
+          .strip_suffix(".d.ts")
+          .or_else(|| path_.strip_suffix(".d.mts"))
+          .or_else(|| path_.strip_suffix(".d.cts"))
+          .unwrap_or(path_);
+        if path_ == path {
+          sloppy_fallback =
+            Some(export.strip_prefix("./").unwrap_or(export).to_string());
+        }
+      }
     }
-    None
+    sloppy_fallback
   }
 
   pub fn lookup_req_for_nv(&self, nv: &PackageNv) -> Option<PackageReq> {
diff --git a/cli/lsp/analysis.rs b/cli/lsp/analysis.rs
index 23b6bb099..133f5f0ac 100644
--- a/cli/lsp/analysis.rs
+++ b/cli/lsp/analysis.rs
@@ -544,7 +544,10 @@ fn fix_ts_import_action(
   action: &tsc::CodeFixAction,
   import_mapper: &TsResponseImportMapper,
 ) -> Result<tsc::CodeFixAction, AnyError> {
-  if action.fix_name == "import" {
+  if matches!(
+    action.fix_name.as_str(),
+    "import" | "fixMissingFunctionDeclaration"
+  ) {
     let change = action
       .changes
       .first()
diff --git a/tests/integration/lsp_tests.rs b/tests/integration/lsp_tests.rs
index 347324899..ed95541d2 100644
--- a/tests/integration/lsp_tests.rs
+++ b/tests/integration/lsp_tests.rs
@@ -5365,6 +5365,126 @@ fn lsp_jsr_auto_import_completion_import_map() {
 }
 
 #[test]
+fn lsp_jsr_code_action_missing_declaration() {
+  let context = TestContextBuilder::new()
+    .use_http_server()
+    .use_temp_cwd()
+    .build();
+  let temp_dir = context.temp_dir();
+  let file = source_file(
+    temp_dir.path().join("file.ts"),
+    r#"
+      import { someFunction } from "jsr:@denotest/types-file";
+      assertReturnType(someFunction());
+    "#,
+  );
+  let mut client = context.new_lsp_command().build();
+  client.initialize_default();
+  client.write_request(
+    "workspace/executeCommand",
+    json!({
+      "command": "deno.cache",
+      "arguments": [[], file.uri()],
+    }),
+  );
+  client.did_open_file(&file);
+  let res = client.write_request(
+    "textDocument/codeAction",
+    json!({
+      "textDocument": {
+        "uri": file.uri(),
+      },
+      "range": {
+        "start": { "line": 2, "character": 6 },
+        "end": { "line": 2, "character": 22 },
+      },
+      "context": {
+        "diagnostics": [
+          {
+            "range": {
+              "start": { "line": 2, "character": 6 },
+              "end": { "line": 2, "character": 22 },
+            },
+            "severity": 8,
+            "code": 2304,
+            "source": "deno-ts",
+            "message": "Cannot find name 'assertReturnType'.",
+            "relatedInformation": [],
+          },
+        ],
+        "only": ["quickfix"],
+      },
+    }),
+  );
+  assert_eq!(
+    res,
+    json!([
+      {
+        "title": "Add missing function declaration 'assertReturnType'",
+        "kind": "quickfix",
+        "diagnostics": [
+          {
+            "range": {
+              "start": {
+                "line": 2,
+                "character": 6,
+              },
+              "end": {
+                "line": 2,
+                "character": 22,
+              },
+            },
+            "severity": 8,
+            "code": 2304,
+            "source": "deno-ts",
+            "message": "Cannot find name 'assertReturnType'.",
+            "relatedInformation": [],
+          },
+        ],
+        "edit": {
+          "documentChanges": [
+            {
+              "textDocument": {
+                "uri": file.uri(),
+                "version": 1,
+              },
+              "edits": [
+                {
+                  "range": {
+                    "start": {
+                      "line": 1,
+                      "character": 6,
+                    },
+                    "end": {
+                      "line": 1,
+                      "character": 6,
+                    },
+                  },
+                  "newText": "import { ReturnType } from \"jsr:@denotest/types-file/types\";\n",
+                },
+                {
+                  "range": {
+                    "start": {
+                      "line": 3,
+                      "character": 0,
+                    },
+                    "end": {
+                      "line": 3,
+                      "character": 0,
+                    },
+                  },
+                  "newText": "\n      function assertReturnType(arg0: ReturnType) {\n        throw new Error(\"Function not implemented.\");\n      }\n",
+                },
+              ],
+            },
+          ],
+        },
+      },
+    ])
+  );
+}
+
+#[test]
 fn lsp_code_actions_deno_cache_npm() {
   let context = TestContextBuilder::new().use_temp_cwd().build();
   let mut client = context.new_lsp_command().build();
diff --git a/tests/registry/jsr/@denotest/types-file/1.0.0/mod.ts b/tests/registry/jsr/@denotest/types-file/1.0.0/mod.ts
new file mode 100644
index 000000000..4d0d73bb5
--- /dev/null
+++ b/tests/registry/jsr/@denotest/types-file/1.0.0/mod.ts
@@ -0,0 +1,5 @@
+import type { ReturnType } from "./types.d.ts";
+
+export function someFunction(): ReturnType {
+  return {};
+}
diff --git a/tests/registry/jsr/@denotest/types-file/1.0.0/types.d.ts b/tests/registry/jsr/@denotest/types-file/1.0.0/types.d.ts
new file mode 100644
index 000000000..dabbb6a37
--- /dev/null
+++ b/tests/registry/jsr/@denotest/types-file/1.0.0/types.d.ts
@@ -0,0 +1 @@
+export interface ReturnType {}
diff --git a/tests/registry/jsr/@denotest/types-file/1.0.0_meta.json b/tests/registry/jsr/@denotest/types-file/1.0.0_meta.json
new file mode 100644
index 000000000..99ba71b5f
--- /dev/null
+++ b/tests/registry/jsr/@denotest/types-file/1.0.0_meta.json
@@ -0,0 +1,28 @@
+{
+  "exports": {
+    ".": "./mod.ts",
+    "./types": "./types.d.ts"
+  },
+  "moduleGraph1": {
+    "/types.d.ts": {},
+    "/mod.ts": {
+      "dependencies": [
+        {
+          "type": "static",
+          "kind": "importType",
+          "specifier": "./types.d.ts",
+          "specifierRange": [
+            [
+              0,
+              42
+            ],
+            [
+              0,
+              46
+            ]
+          ]
+        }
+      ]
+    }
+  }
+}
diff --git a/tests/registry/jsr/@denotest/types-file/meta.json b/tests/registry/jsr/@denotest/types-file/meta.json
new file mode 100644
index 000000000..02601e4d0
--- /dev/null
+++ b/tests/registry/jsr/@denotest/types-file/meta.json
@@ -0,0 +1,5 @@
+{
+  "versions": {
+    "1.0.0": {}
+  }
+}