enhance `if_return` to handle `return void...` (#1977)

fixes #512

3 files changed, 28 insertions, 2 deletions

diff --git a/test/compress/if_return.js b/test/compress/if_return.js
index 0ac45c3c..c09d67b6 100644
--- a/test/compress/if_return.js
+++ b/test/compress/if_return.js
@@ -302,3 +302,25 @@ issue_1437_conditionals: {
         }
     }
 }
+
+issue_512: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function a() {
+            if (b()) {
+                c();
+                return;
+            }
+            throw e;
+        }
+    }
+    expect: {
+        function a() {
+            if (!b()) throw e;
+            c();
+        }
+    }
+}
diff --git a/test/mocha/cli.js b/test/mocha/cli.js
index 335b224d..db4a2c33 100644
--- a/test/mocha/cli.js
+++ b/test/mocha/cli.js
@@ -19,7 +19,9 @@ describe("bin/uglifyjs", function () {
             eval(stdout);
 
             assert.strictEqual(typeof WrappedUglifyJS, 'object');
-            assert.strictEqual(WrappedUglifyJS.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
+            var result = WrappedUglifyJS.minify("foo([true,,2+3]);");
+            assert.strictEqual(result.error, undefined);
+            assert.strictEqual(result.code, "foo([!0,,5]);");
 
             done();
         });
diff --git a/test/mocha/spidermonkey.js b/test/mocha/spidermonkey.js
index a8a112d0..9bddb537 100644
--- a/test/mocha/spidermonkey.js
+++ b/test/mocha/spidermonkey.js
@@ -15,7 +15,9 @@ describe("spidermonkey export/import sanity test", function() {
 
             eval(stdout);
             assert.strictEqual(typeof SpiderUglify, "object");
-            assert.strictEqual(SpiderUglify.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
+            var result = SpiderUglify.minify("foo([true,,2+3]);");
+            assert.strictEqual(result.error, undefined);
+            assert.strictEqual(result.code, "foo([!0,,5]);");
 
             done();
         });