From: Alex Lam S.L <alexlamsl@gmail.com>
Date: Sun, 10 May 2020 17:07:05 +0000 (+0100)
Subject: retain `@__PURE__` call when return value is used (#3874)
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=7e0ad232b079202024ea845a2076ee78e1e0dbd7;p=UglifyJS.git

retain `@__PURE__` call when return value is used (#3874)
---

diff --git a/lib/compress.js b/lib/compress.js
index 5509137b..6a444e92 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -3499,6 +3499,7 @@ merge(Compressor.prototype, {
             if (fn instanceof AST_Lambda) {
                 if (fn.evaluating) return this;
                 if (fn.name && fn.name.definition().recursive_refs > 0) return this;
+                if (this.is_expr_pure(compressor)) return this;
                 var stat = fn.first_statement();
                 if (!(stat instanceof AST_Return)) return this;
                 var args = eval_args(this.args);
diff --git a/test/compress/pure_funcs.js b/test/compress/pure_funcs.js
index 15ddf095..d65399f1 100644
--- a/test/compress/pure_funcs.js
+++ b/test/compress/pure_funcs.js
@@ -782,3 +782,28 @@ inline_pure_call_3: {
         "undefined",
     ]
 }
+
+inline_pure_call_4: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = /*@__PURE__*/ function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "42",
+    ]
+}