fix: wrong type information for #await with same id (#371)

* fix: wrong type information for `#await` with same id

* Create twenty-pandas-tie.md

* fix

Author: ota-meshi

.changeset/twenty-pandas-tie.md

@@ -0,0 +1,5 @@
+---
+"svelte-eslint-parser": patch
+---
+
+fix: wrong type information for `#await` with same id

src/parser/converts/block.ts

@@ -307,7 +307,11 @@ export function convertAwaitBlock(
           };
         }
         const idAwaitThenValue = typeCtx.generateUniqueId("AwaitThenValue");
-        if (node.expression.type === "Identifier") {
+        if (
+          node.expression.type === "Identifier" &&
+          // We cannot use type annotations like `(x: Foo<x>)` if they have the same identifier name.
+          !hasIdentifierFor(node.expression.name, baseParam.node)
+        ) {
           return {
             preparationScript: [generateAwaitThenValueType(idAwaitThenValue)],
             param: {
@@ -484,3 +488,30 @@ function generateAwaitThenValueType(id: string) {
         : never
         : T;`;
 }
+
+/** Checks whether the given name identifier is exists or not. */
+function hasIdentifierFor(name: string, node: ESTree.Pattern): boolean {
+  if (node.type === "Identifier") {
+    return node.name === name;
+  }
+  if (node.type === "ObjectPattern") {
+    return node.properties.some((property) =>
+      property.type === "Property"
+        ? hasIdentifierFor(name, property.value)
+        : hasIdentifierFor(name, property)
+    );
+  }
+  if (node.type === "ArrayPattern") {
+    return node.elements.some(
+      (element) => element && hasIdentifierFor(name, element)
+    );
+  }
+  if (node.type === "RestElement") {
+    return hasIdentifierFor(name, node.argument);
+  }
+  if (node.type === "AssignmentPattern") {
+    return hasIdentifierFor(name, node.left);
+  }
+
+  return false;
+}

tests/fixtures/integrations/type-info-tests/await-with-same-id-input.svelte

@@ -0,0 +1,37 @@
+<script lang="ts">
+    let a: Promise<{ x: number }>
+    let b: Promise<{ x: number }>
+    let c: Promise<{ x: number }>
+    let d: Promise<number[]>
+    let e: Promise<number[]>
+</script>
+
+{#await a}
+    <div>await</div>
+{:then a}
+    <div>{a.x}</div>
+{/await}
+
+{#await b}
+    <div>await</div>
+{:then { x: b = 42 }}
+    <div>{b.toExponential()}</div>
+{/await}
+
+{#await c}
+    <div>await</div>
+{:then {...c}}
+    <div>{c.x}</div>
+{/await}
+
+{#await d}
+    <div>await</div>
+{:then [d]}
+    <div>{d.toExponential()}</div>
+{/await}
+
+{#await e}
+    <div>await</div>
+{:then [...e]}
+    <div>{e[0].toExponential()}</div>
+{/await}

tests/fixtures/integrations/type-info-tests/await-with-same-id-output.json

@@ -0,0 +1 @@
+[]

tests/fixtures/integrations/type-info-tests/await-with-same-id-setup.ts

@@ -0,0 +1,24 @@
+/* eslint eslint-comments/require-description: 0, @typescript-eslint/explicit-module-boundary-types: 0 */
+import type { Linter } from "eslint";
+import { generateParserOptions } from "../../../src/parser/test-utils";
+import { rules } from "@typescript-eslint/eslint-plugin";
+export function setupLinter(linter: Linter) {
+  linter.defineRule(
+    "@typescript-eslint/no-unsafe-member-access",
+    rules["no-unsafe-member-access"] as never
+  );
+}
+
+export function getConfig() {
+  return {
+    parser: "svelte-eslint-parser",
+    parserOptions: generateParserOptions(),
+    rules: {
+      "@typescript-eslint/no-unsafe-member-access": "error",
+    },
+    env: {
+      browser: true,
+      es2021: true,
+    },
+  };
+}

tests/fixtures/parser/ast/ts-store01-input.svelte

@@ -11,4 +11,4 @@
 {$b}
 {c}
 {$c}
-{$d}
+{$unknown}

tests/fixtures/parser/ast/ts-store01-no-undef-result.json

@@ -1,7 +1,7 @@
 [
   {
     "ruleId": "no-undef",
-    "code": "$d",
+    "code": "$unknown",
     "line": 14,
     "column": 2
   }

tests/fixtures/parser/ast/ts-store01-output.json

@@ -1012,10 +1012,10 @@
       "kind": "text",
       "expression": {
         "type": "Identifier",
-        "name": "$d",
+        "name": "$unknown",
         "range": [
           197,
-          199
+          205
         ],
         "loc": {
           "start": {
@@ -1024,13 +1024,13 @@
           },
           "end": {
             "line": 14,
-            "column": 3
+            "column": 9
           }
         }
       },
       "range": [
         196,
-        200
+        206
       ],
       "loc": {
         "start": {
@@ -1039,7 +1039,7 @@
         },
         "end": {
           "line": 14,
-          "column": 4
+          "column": 10
         }
       }
     }
@@ -2291,10 +2291,10 @@
     },
     {
       "type": "Identifier",
-      "value": "$d",
+      "value": "$unknown",
       "range": [
         197,
-        199
+        205
       ],
       "loc": {
         "start": {
@@ -2303,32 +2303,32 @@
         },
         "end": {
           "line": 14,
-          "column": 3
+          "column": 9
         }
       }
     },
     {
       "type": "Punctuator",
       "value": "}",
       "range": [
-        199,
-        200
+        205,
+        206
       ],
       "loc": {
         "start": {
           "line": 14,
-          "column": 3
+          "column": 9
         },
         "end": {
           "line": 14,
-          "column": 4
+          "column": 10
         }
       }
     }
   ],
   "range": [
     0,
-    201
+    207
   ],
   "loc": {
     "start": {

tests/fixtures/parser/ast/ts-store01-scope-output.json

@@ -10847,10 +10847,10 @@
         {
           "identifier": {
             "type": "Identifier",
-            "name": "$d",
+            "name": "$unknown",
             "range": [
               197,
-              199
+              205
             ],
             "loc": {
               "start": {
@@ -10859,7 +10859,7 @@
               },
               "end": {
                 "line": 14,
-                "column": 3
+                "column": 9
               }
             }
           },
@@ -10873,10 +10873,10 @@
         {
           "identifier": {
             "type": "Identifier",
-            "name": "$d",
+            "name": "$unknown",
             "range": [
               197,
-              199
+              205
             ],
             "loc": {
               "start": {
@@ -10885,7 +10885,7 @@
               },
               "end": {
                 "line": 14,
-                "column": 3
+                "column": 9
               }
             }
           },
@@ -10900,10 +10900,10 @@
     {
       "identifier": {
         "type": "Identifier",
-        "name": "$d",
+        "name": "$unknown",
         "range": [
           197,
-          199
+          205
         ],
         "loc": {
           "start": {
@@ -10912,7 +10912,7 @@
           },
           "end": {
             "line": 14,
-            "column": 3
+            "column": 9
           }
         }
       },

tests/fixtures/parser/ast/ts-store01-type-output.svelte

@@ -11,4 +11,4 @@
 {$b} <!-- $b: "abc" -->
 {c} <!-- c: "abc" -->
 {$c} <!-- $c: any -->
-{$d} <!-- $d: any -->
+{$unknown} <!-- $unknown: any -->