From e02a0f2a450da7591b8baf5700eb771ff604e1b8 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Thu, 27 Sep 2018 16:11:46 -0700
Subject: [PATCH] Fix parent points in unreachable code (#27400)

In the binder, unreachable code mistakenly skips the `bindJSDoc` call in
`bindChildrenWorker`, which sets parent pointers. The fix is to call
`bindJSDoc` in the case of unreachable code as well.
---
 src/compiler/binder.ts                            |  1 +
 .../jsdocBindingInUnreachableCode.symbols         | 12 ++++++++++++
 .../reference/jsdocBindingInUnreachableCode.types | 15 +++++++++++++++
 .../jsdoc/jsdocBindingInUnreachableCode.ts        | 11 +++++++++++
 4 files changed, 39 insertions(+)
 create mode 100644 tests/baselines/reference/jsdocBindingInUnreachableCode.symbols
 create mode 100644 tests/baselines/reference/jsdocBindingInUnreachableCode.types
 create mode 100644 tests/cases/conformance/jsdoc/jsdocBindingInUnreachableCode.ts

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 38d6f55824254..b7d0d6f0f0eb6 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -640,6 +640,7 @@ namespace ts {
         function bindChildrenWorker(node: Node): void {
             if (checkUnreachable(node)) {
                 bindEachChild(node);
+                bindJSDoc(node);
                 return;
             }
             switch (node.kind) {
diff --git a/tests/baselines/reference/jsdocBindingInUnreachableCode.symbols b/tests/baselines/reference/jsdocBindingInUnreachableCode.symbols
new file mode 100644
index 0000000000000..62ef96f854a44
--- /dev/null
+++ b/tests/baselines/reference/jsdocBindingInUnreachableCode.symbols
@@ -0,0 +1,12 @@
+=== tests/cases/conformance/jsdoc/bug27341.js ===
+if (false) {
+    /**
+     * @param {string} s
+     */
+    const x = function (s) {
+>x : Symbol(x, Decl(bug27341.js, 4, 9))
+>s : Symbol(s, Decl(bug27341.js, 4, 24))
+
+    };
+}
+
diff --git a/tests/baselines/reference/jsdocBindingInUnreachableCode.types b/tests/baselines/reference/jsdocBindingInUnreachableCode.types
new file mode 100644
index 0000000000000..d1d01d17e969b
--- /dev/null
+++ b/tests/baselines/reference/jsdocBindingInUnreachableCode.types
@@ -0,0 +1,15 @@
+=== tests/cases/conformance/jsdoc/bug27341.js ===
+if (false) {
+>false : false
+
+    /**
+     * @param {string} s
+     */
+    const x = function (s) {
+>x : (s: string) => void
+>function (s) {    } : (s: string) => void
+>s : string
+
+    };
+}
+
diff --git a/tests/cases/conformance/jsdoc/jsdocBindingInUnreachableCode.ts b/tests/cases/conformance/jsdoc/jsdocBindingInUnreachableCode.ts
new file mode 100644
index 0000000000000..2c4accf993b22
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/jsdocBindingInUnreachableCode.ts
@@ -0,0 +1,11 @@
+// @allowJs: true
+// @noEmit: true
+// @checkJs: true
+// @Filename: bug27341.js
+if (false) {
+    /**
+     * @param {string} s
+     */
+    const x = function (s) {
+    };
+}