From 63be1f3a4d5d10ba923dd40ffd55f4e5b7d41372 Mon Sep 17 00:00:00 2001
From: Richard van Velzen <rvanvelzen@experty.com>
Date: Sun, 15 May 2016 21:00:51 +0200
Subject: [PATCH] Only allow `var` definitions to be moved into the for-init
 clause

Fixes #1079
---
 lib/compress.js            |  2 +-
 test/compress/join-vars.js | 40 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 1 deletion(-)
 create mode 100644 test/compress/join-vars.js

diff --git a/lib/compress.js b/lib/compress.js
index 51122751..6fbe2c8b 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -802,7 +802,7 @@ merge(Compressor.prototype, {
                     CHANGED = true;
                 }
                 else if (stat instanceof AST_For
-                         && prev instanceof AST_Definitions
+                         && prev instanceof AST_Var
                          && (!stat.init || stat.init.TYPE == prev.TYPE)) {
                     CHANGED = true;
                     a.pop();
diff --git a/test/compress/join-vars.js b/test/compress/join-vars.js
new file mode 100644
index 00000000..ea6077b6
--- /dev/null
+++ b/test/compress/join-vars.js
@@ -0,0 +1,40 @@
+only_vars: {
+    options = { join_vars: true };
+    input: {
+        let netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        let netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}
+
+issue_1079_with_vars: {
+    options = { join_vars: true };
+    input: {
+        var netmaskBinary = '';
+        for (var i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        for (var netmaskBinary = '', i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}
+
+issue_1079_with_mixed: {
+    options = { join_vars: true };
+    input: {
+        var netmaskBinary = '';
+        for (let i = 0; i < netmaskBits; ++i) {
+            netmaskBinary += '1';
+        }
+    }
+    expect: {
+        var netmaskBinary = ''
+        for (let i = 0; i < netmaskBits; ++i) netmaskBinary += '1';
+    }
+}
\ No newline at end of file