From 9fb6acf1e1cdc768cdf6598d04dc3024c45d16f8 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Tue, 10 Nov 2020 11:28:49 -0800
Subject: [PATCH] Add missed resolveSymbol in commonjs import resolution
 (#41479)

Fixes resolution of export aliases in the postfix-property-access case
of commonjs require:

```js
const { x } = require('./foo').nested
x
```

This program would previously fail if `x` was an export alias.

Fixes #41422
---
 src/compiler/checker.ts                       |  2 +-
 .../reference/commonJSReexport.symbols        | 41 ++++++++++++++++
 .../reference/commonJSReexport.types          | 49 +++++++++++++++++++
 .../conformance/salsa/commonJSReexport.ts     | 19 +++++++
 4 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 tests/baselines/reference/commonJSReexport.symbols
 create mode 100644 tests/baselines/reference/commonJSReexport.types
 create mode 100644 tests/cases/conformance/salsa/commonJSReexport.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 9a71a6a0277e8..74a48de2be46e 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2790,7 +2790,7 @@ namespace ts {
             const resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
             const name = node.propertyName || node.name;
             if (commonJSPropertyAccess && resolved && isIdentifier(name)) {
-                return getPropertyOfType(getTypeOfSymbol(resolved), name.escapedText);
+                return resolveSymbol(getPropertyOfType(getTypeOfSymbol(resolved), name.escapedText), dontResolveAlias);
             }
             markSymbolOfAliasDeclarationIfTypeOnly(node, /*immediateTarget*/ undefined, resolved, /*overwriteEmpty*/ false);
             return resolved;
diff --git a/tests/baselines/reference/commonJSReexport.symbols b/tests/baselines/reference/commonJSReexport.symbols
new file mode 100644
index 0000000000000..7b31548415ffd
--- /dev/null
+++ b/tests/baselines/reference/commonJSReexport.symbols
@@ -0,0 +1,41 @@
+=== tests/cases/conformance/salsa/main.js ===
+const { hardline } = require('./second').nested;
+>hardline : Symbol(hardline, Decl(main.js, 0, 7))
+>require('./second').nested : Symbol(nested, Decl(second.js, 0, 18))
+>require : Symbol(require)
+>'./second' : Symbol("tests/cases/conformance/salsa/second", Decl(second.js, 0, 0))
+>nested : Symbol(nested, Decl(second.js, 0, 18))
+
+hardline
+>hardline : Symbol(hardline, Decl(main.js, 0, 7))
+
+=== tests/cases/conformance/salsa/first.js ===
+// #41422, based on prettier's exports
+
+const hardline = { type: "hard" }
+>hardline : Symbol(hardline, Decl(first.js, 2, 5))
+>type : Symbol(type, Decl(first.js, 2, 18))
+
+module.exports = {
+>module.exports : Symbol("tests/cases/conformance/salsa/first", Decl(first.js, 0, 0))
+>module : Symbol(module, Decl(first.js, 2, 33))
+>exports : Symbol("tests/cases/conformance/salsa/first", Decl(first.js, 0, 0))
+
+  hardline
+>hardline : Symbol(hardline, Decl(first.js, 3, 18))
+}
+
+
+=== tests/cases/conformance/salsa/second.js ===
+module.exports = {
+>module.exports : Symbol("tests/cases/conformance/salsa/second", Decl(second.js, 0, 0))
+>module : Symbol(export=, Decl(second.js, 0, 0))
+>exports : Symbol(export=, Decl(second.js, 0, 0))
+
+  nested: require('./first')
+>nested : Symbol(nested, Decl(second.js, 0, 18))
+>require : Symbol(require)
+>'./first' : Symbol("tests/cases/conformance/salsa/first", Decl(first.js, 0, 0))
+
+};
+
diff --git a/tests/baselines/reference/commonJSReexport.types b/tests/baselines/reference/commonJSReexport.types
new file mode 100644
index 0000000000000..84e98c4fea008
--- /dev/null
+++ b/tests/baselines/reference/commonJSReexport.types
@@ -0,0 +1,49 @@
+=== tests/cases/conformance/salsa/main.js ===
+const { hardline } = require('./second').nested;
+>hardline : { type: string; }
+>require('./second').nested : typeof import("tests/cases/conformance/salsa/first")
+>require('./second') : { nested: typeof import("tests/cases/conformance/salsa/first"); }
+>require : any
+>'./second' : "./second"
+>nested : typeof import("tests/cases/conformance/salsa/first")
+
+hardline
+>hardline : { type: string; }
+
+=== tests/cases/conformance/salsa/first.js ===
+// #41422, based on prettier's exports
+
+const hardline = { type: "hard" }
+>hardline : { type: string; }
+>{ type: "hard" } : { type: string; }
+>type : string
+>"hard" : "hard"
+
+module.exports = {
+>module.exports = {  hardline} : typeof import("tests/cases/conformance/salsa/first")
+>module.exports : typeof import("tests/cases/conformance/salsa/first")
+>module : { "\"tests/cases/conformance/salsa/first\"": typeof import("tests/cases/conformance/salsa/first"); }
+>exports : typeof import("tests/cases/conformance/salsa/first")
+>{  hardline} : { hardline: { type: string; }; }
+
+  hardline
+>hardline : { type: string; }
+}
+
+
+=== tests/cases/conformance/salsa/second.js ===
+module.exports = {
+>module.exports = {  nested: require('./first')} : { nested: typeof import("tests/cases/conformance/salsa/first"); }
+>module.exports : { nested: typeof import("tests/cases/conformance/salsa/first"); }
+>module : { "\"tests/cases/conformance/salsa/second\"": { nested: typeof import("tests/cases/conformance/salsa/first"); }; }
+>exports : { nested: typeof import("tests/cases/conformance/salsa/first"); }
+>{  nested: require('./first')} : { nested: typeof import("tests/cases/conformance/salsa/first"); }
+
+  nested: require('./first')
+>nested : typeof import("tests/cases/conformance/salsa/first")
+>require('./first') : typeof import("tests/cases/conformance/salsa/first")
+>require : any
+>'./first' : "./first"
+
+};
+
diff --git a/tests/cases/conformance/salsa/commonJSReexport.ts b/tests/cases/conformance/salsa/commonJSReexport.ts
new file mode 100644
index 0000000000000..e3220c5c24842
--- /dev/null
+++ b/tests/cases/conformance/salsa/commonJSReexport.ts
@@ -0,0 +1,19 @@
+// #41422, based on prettier's exports
+// @noEmit: true
+// @checkJS: true
+
+// @filename: first.js
+const hardline = { type: "hard" }
+module.exports = {
+  hardline
+}
+
+
+// @filename: second.js
+module.exports = {
+  nested: require('./first')
+};
+
+// @filename: main.js
+const { hardline } = require('./second').nested;
+hardline