From 08d9d6dd8d222ddaca86db6647f124bd7dbaa28f Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Fri, 19 Mar 2021 17:02:23 +0800
Subject: [PATCH 1/3] fix(compiler-sfc): should not rewrite scope variable

---
 .../__snapshots__/compileScript.spec.ts.snap  | 26 ++++++++++++
 .../__tests__/compileScript.spec.ts           | 23 +++++++++++
 packages/compiler-sfc/src/compileScript.ts    | 40 ++++++++++++++-----
 3 files changed, 79 insertions(+), 10 deletions(-)

diff --git a/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap b/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
index 59ef9b1b7ee..2293228e7fa 100644
--- a/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
+++ b/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
@@ -508,6 +508,32 @@ return { n, a, b, c }
 }"
 `;
 
+exports[`SFC compile <script setup> ref: syntax sugar avoid rewrite variable if has same name scoped variable declaration in parent block 1`] = `
+"import { ref as _ref } from 'vue'
+
+export default {
+  expose: [],
+  setup(__props) {
+
+        const a = _ref(1)
+        const b = _ref(1)
+        const d = _ref(1)
+        function test() {
+          const a = 2
+          console.log(a)
+          console.log(b.value)
+          let c = { c: 3 }
+          console.log(c)
+          let $d
+          console.log($d)
+        }
+      
+return { a, b, d, test }
+}
+
+}"
+`;
+
 exports[`SFC compile <script setup> ref: syntax sugar convert ref declarations 1`] = `
 "import { ref as _ref } from 'vue'
 
diff --git a/packages/compiler-sfc/__tests__/compileScript.spec.ts b/packages/compiler-sfc/__tests__/compileScript.spec.ts
index 0594bf26dbf..545b632eeec 100644
--- a/packages/compiler-sfc/__tests__/compileScript.spec.ts
+++ b/packages/compiler-sfc/__tests__/compileScript.spec.ts
@@ -708,6 +708,29 @@ const emit = defineEmit(['a', 'b'])
       assertCode(content)
     })
 
+    // #3445
+    test('avoid rewrite variable if has same name scoped variable declaration in parent block', () => {
+      const { content } = compile(`
+      <script setup>
+        ref: a = 1
+        ref: b = 1
+        ref: d = 1
+        function test() {
+          const a = 2
+          console.log(a)
+          console.log(b)
+          let c = { c: 3 }
+          console.log(c)
+          let $d
+          console.log($d)
+        }
+      </script>`)
+      expect(content).toMatch('console.log(a)')
+      expect(content).toMatch('console.log(b.value)')
+      expect(content).toMatch('console.log(c)')
+      assertCode(content)
+    })
+
     test('object destructure', () => {
       const { content, bindings } = compile(`<script setup>
       ref: n = 1, ({ a, b: c, d = 1, e: f = 2, ...g } = useFoo())
diff --git a/packages/compiler-sfc/src/compileScript.ts b/packages/compiler-sfc/src/compileScript.ts
index 74430499df0..0bf5fc7b1d1 100644
--- a/packages/compiler-sfc/src/compileScript.ts
+++ b/packages/compiler-sfc/src/compileScript.ts
@@ -1344,6 +1344,23 @@ function genRuntimeEmits(emits: Set<string>) {
     : ``
 }
 
+function markScopeIdentifier(
+  node: Node & { scopeIds?: Set<string> },
+  child: Identifier,
+  knownIds: Record<string, number>
+) {
+  const { name } = child
+  if (node.scopeIds && node.scopeIds.has(name)) {
+    return
+  }
+  if (name in knownIds) {
+    knownIds[name]++
+  } else {
+    knownIds[name] = 1
+  }
+  ;(node.scopeIds || (node.scopeIds = new Set())).add(name)
+}
+
 /**
  * Walk an AST and find identifiers that are variable references.
  * This is largely the same logic with `transformExpressions` in compiler-core
@@ -1366,6 +1383,18 @@ function walkIdentifiers(
         ) {
           onIdentifier(node, parent!, parentStack)
         }
+      } else if (node.type === 'BlockStatement' && isFunction(parent!)) {
+        node.body.forEach(p => {
+          if (p.type === 'VariableDeclaration') {
+            ;(walk as any)(p, {
+              enter(child: Node, parent: Node) {
+                if (child.type === 'Identifier') {
+                  markScopeIdentifier(node, child, knownIds)
+                }
+              }
+            })
+          }
+        })
       } else if (isFunction(node)) {
         // walk function expressions and add its arguments to known identifiers
         // so that we don't prefix them
@@ -1384,16 +1413,7 @@ function walkIdentifiers(
                   parent.right === child
                 )
               ) {
-                const { name } = child
-                if (node.scopeIds && node.scopeIds.has(name)) {
-                  return
-                }
-                if (name in knownIds) {
-                  knownIds[name]++
-                } else {
-                  knownIds[name] = 1
-                }
-                ;(node.scopeIds || (node.scopeIds = new Set())).add(name)
+                markScopeIdentifier(node, child, knownIds)
               }
             }
           })

From 056cdfc6edd13ce2c6ab4eb3516f4c1b4b5f51a5 Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Fri, 19 Mar 2021 23:23:02 +0800
Subject: [PATCH 2/3] test: update test case

---
 packages/compiler-sfc/__tests__/compileScript.spec.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/compiler-sfc/__tests__/compileScript.spec.ts b/packages/compiler-sfc/__tests__/compileScript.spec.ts
index 545b632eeec..d8ef525182b 100644
--- a/packages/compiler-sfc/__tests__/compileScript.spec.ts
+++ b/packages/compiler-sfc/__tests__/compileScript.spec.ts
@@ -728,6 +728,7 @@ const emit = defineEmit(['a', 'b'])
       expect(content).toMatch('console.log(a)')
       expect(content).toMatch('console.log(b.value)')
       expect(content).toMatch('console.log(c)')
+      expect(content).toMatch('console.log($d)')
       assertCode(content)
     })
 

From 105fcdddec944a7b63ca72f507783529aa9941b1 Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Mon, 22 Mar 2021 13:20:26 +0800
Subject: [PATCH 3/3] chore: improve code

---
 .../__snapshots__/compileScript.spec.ts.snap  | 55 ++++++++++---------
 .../__tests__/compileScript.spec.ts           |  8 ++-
 packages/compiler-sfc/src/compileScript.ts    | 27 +++++----
 3 files changed, 50 insertions(+), 40 deletions(-)

diff --git a/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap b/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
index 2293228e7fa..c27f0aeabe2 100644
--- a/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
+++ b/packages/compiler-sfc/__tests__/__snapshots__/compileScript.spec.ts.snap
@@ -508,32 +508,6 @@ return { n, a, b, c }
 }"
 `;
 
-exports[`SFC compile <script setup> ref: syntax sugar avoid rewrite variable if has same name scoped variable declaration in parent block 1`] = `
-"import { ref as _ref } from 'vue'
-
-export default {
-  expose: [],
-  setup(__props) {
-
-        const a = _ref(1)
-        const b = _ref(1)
-        const d = _ref(1)
-        function test() {
-          const a = 2
-          console.log(a)
-          console.log(b.value)
-          let c = { c: 3 }
-          console.log(c)
-          let $d
-          console.log($d)
-        }
-      
-return { a, b, d, test }
-}
-
-}"
-`;
-
 exports[`SFC compile <script setup> ref: syntax sugar convert ref declarations 1`] = `
 "import { ref as _ref } from 'vue'
 
@@ -652,6 +626,35 @@ return {  }
 }"
 `;
 
+exports[`SFC compile <script setup> ref: syntax sugar should not rewrite scope variable 1`] = `
+"import { ref as _ref } from 'vue'
+
+export default {
+  expose: [],
+  setup(__props) {
+
+        const a = _ref(1)
+        const b = _ref(1)
+        const d = _ref(1)
+        const e = 1
+        function test() {
+          const a = 2
+          console.log(a)
+          console.log(b.value)
+          let c = { c: 3 }
+          console.log(c)
+          let $d
+          console.log($d)
+          console.log(d.value)
+          console.log(e)
+        }
+      
+return { a, b, d, e, test }
+}
+
+}"
+`;
+
 exports[`SFC compile <script setup> ref: syntax sugar using ref binding in property shorthand 1`] = `
 "import { ref as _ref } from 'vue'
 
diff --git a/packages/compiler-sfc/__tests__/compileScript.spec.ts b/packages/compiler-sfc/__tests__/compileScript.spec.ts
index d8ef525182b..30cef0fbcd4 100644
--- a/packages/compiler-sfc/__tests__/compileScript.spec.ts
+++ b/packages/compiler-sfc/__tests__/compileScript.spec.ts
@@ -708,13 +708,13 @@ const emit = defineEmit(['a', 'b'])
       assertCode(content)
     })
 
-    // #3445
-    test('avoid rewrite variable if has same name scoped variable declaration in parent block', () => {
+    test('should not rewrite scope variable', () => {
       const { content } = compile(`
       <script setup>
         ref: a = 1
         ref: b = 1
         ref: d = 1
+        const e = 1
         function test() {
           const a = 2
           console.log(a)
@@ -723,12 +723,16 @@ const emit = defineEmit(['a', 'b'])
           console.log(c)
           let $d
           console.log($d)
+          console.log(d)
+          console.log(e)
         }
       </script>`)
       expect(content).toMatch('console.log(a)')
       expect(content).toMatch('console.log(b.value)')
       expect(content).toMatch('console.log(c)')
       expect(content).toMatch('console.log($d)')
+      expect(content).toMatch('console.log(d.value)')
+      expect(content).toMatch('console.log(e)')
       assertCode(content)
     })
 
diff --git a/packages/compiler-sfc/src/compileScript.ts b/packages/compiler-sfc/src/compileScript.ts
index 0bf5fc7b1d1..864fcbbbf7c 100644
--- a/packages/compiler-sfc/src/compileScript.ts
+++ b/packages/compiler-sfc/src/compileScript.ts
@@ -1383,19 +1383,22 @@ function walkIdentifiers(
         ) {
           onIdentifier(node, parent!, parentStack)
         }
-      } else if (node.type === 'BlockStatement' && isFunction(parent!)) {
-        node.body.forEach(p => {
-          if (p.type === 'VariableDeclaration') {
-            ;(walk as any)(p, {
-              enter(child: Node, parent: Node) {
-                if (child.type === 'Identifier') {
-                  markScopeIdentifier(node, child, knownIds)
-                }
-              }
-            })
-          }
-        })
       } else if (isFunction(node)) {
+        // #3445
+        // should not rewrite local variables sharing a name with a top-level ref
+        if (node.body.type === 'BlockStatement') {
+          node.body.body.forEach(p => {
+            if (p.type === 'VariableDeclaration') {
+              ;(walk as any)(p, {
+                enter(child: Node) {
+                  if (child.type === 'Identifier') {
+                    markScopeIdentifier(node, child, knownIds)
+                  }
+                }
+              })
+            }
+          })
+        }
         // walk function expressions and add its arguments to known identifiers
         // so that we don't prefix them
         node.params.forEach(p =>