From dfd6418878495eb6ff22a83a9765478bdf0e1e17 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Fri, 14 Jan 2022 20:18:35 +0000
Subject: [PATCH] fix corner case in `inline` (#5297)

fixes #5296
---
 lib/compress.js              | 12 ++++++----
 test/compress/drop-unused.js | 15 ++++++++-----
 test/compress/functions.js   | 43 ++++++++++++++++++++++++++++++++----
 test/compress/if_return.js   |  6 ++---
 4 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/lib/compress.js b/lib/compress.js
index 473fd38c..f754c43f 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -3540,8 +3540,9 @@ Compressor.prototype.compress = function(node) {
                     changed = true;
                 }
             }
+            var loop = in_loop && in_try && in_try.bfinally ? "try" : in_loop;
             for (; index >= 0; index--) {
-                var inlined = statements[index].try_inline(compressor, block_scope, true, in_loop);
+                var inlined = statements[index].try_inline(compressor, block_scope, true, loop);
                 if (!inlined) continue;
                 statements[index] = inlined;
                 changed = true;
@@ -13263,6 +13264,11 @@ Compressor.prototype.compress = function(node) {
             return this;
         });
         def(AST_New, noop);
+        def(AST_Return, function(compressor, scope, no_return, in_loop) {
+            var value = this.value;
+            if (value) value = value.try_inline(compressor, scope, undefined, in_loop === "try");
+            return value || this;
+        });
         function inline_sequence(compressor, scope, no_return, in_loop, node, skip) {
             var body = [], exprs = node.expressions, no_ret = no_return;
             for (var i = exprs.length - (skip || 0), j = i; --i >= 0; no_ret = true) {
@@ -13363,10 +13369,8 @@ Compressor.prototype.compress = function(node) {
 
     OPT(AST_Return, function(self, compressor) {
         var value = self.value;
-        if (!value) return self;
-        var inlined = value.try_inline(compressor);
-        if (inlined) return inlined;
         if (compressor.option("side_effects")
+            && value
             && is_undefined(value, compressor)
             && !in_async_generator(compressor.find_parent(AST_Scope))) {
             self.value = null;
diff --git a/test/compress/drop-unused.js b/test/compress/drop-unused.js
index 36aa2a9e..27d0fe3f 100644
--- a/test/compress/drop-unused.js
+++ b/test/compress/drop-unused.js
@@ -1233,8 +1233,11 @@ issue_2105_2: {
 issue_2105_3: {
     options = {
         inline: true,
-        passes: 2,
+        join_vars: true,
+        passes: 3,
         reduce_vars: true,
+        side_effects: true,
+        sequences: true,
         unused: true,
     }
     input: {
@@ -1258,12 +1261,12 @@ issue_2105_3: {
         });
     }
     expect: {
-        !void void {
+        ({
             prop: function() {
-                console.log;
-                void console.log("PASS");
-            }
-        }.prop();
+                console.log,
+                console.log("PASS");
+            },
+        }).prop();
     }
     expect_stdout: "PASS"
 }
diff --git a/test/compress/functions.js b/test/compress/functions.js
index 19374b01..434c7589 100644
--- a/test/compress/functions.js
+++ b/test/compress/functions.js
@@ -6152,10 +6152,8 @@ issue_4265: {
     }
     expect: {
         function f() {
-            return console, function() {
-                console.log(a);
-                var a;
-            }(), 0;
+            var a;
+            return console, console.log(a), 0;
         }
         f();
     }
@@ -8046,3 +8044,40 @@ issue_5290: {
     }
     expect_stdout: "PASS"
 }
+
+issue_5296: {
+    options = {
+        inline: true,
+    }
+    input: {
+        var a = "PASS";
+        (function() {
+            for (var i = 0; i < 2; i++)
+                try {
+                    return function() {
+                        while (!console);
+                        var b = b && (a = b) || "FAIL";
+                    }();
+                } finally {
+                    continue;
+                }
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (function() {
+            for (var i = 0; i < 2; i++)
+                try {
+                    b = void 0;
+                    while (!console);
+                    var b = b && (a = b) || "FAIL";
+                    return;
+                } finally {
+                    continue;
+                }
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
diff --git a/test/compress/if_return.js b/test/compress/if_return.js
index e19ca6fa..2d139698 100644
--- a/test/compress/if_return.js
+++ b/test/compress/if_return.js
@@ -595,10 +595,10 @@ issue_3600_2: {
     expect: {
         var c = 0;
         (function() {
-            if ([][c++]) {
-                var b = --b;
+            if ([][c++])
+                b = --b,
                 c = 42;
-            }
+            var b;
         })();
         console.log(c);
     }