From 3b28b915ebad2d9452c0e8649033ab4813eabca4 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Fri, 24 Nov 2017 14:07:39 +0800
Subject: [PATCH] extend escape analysis on constant expression properties
 (#2509)

fixes #2508
---
 lib/compress.js              |  16 +++--
 test/compress/hoist_props.js | 133 +++++++++++++++++++++++++++++++++++
 2 files changed, 142 insertions(+), 7 deletions(-)

diff --git a/lib/compress.js b/lib/compress.js
index d8a0bd7c..744a1ea5 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -333,7 +333,7 @@ merge(Compressor.prototype, {
                             }
                         }
                     }
-                    mark_escaped(d, node, value, 0);
+                    mark_escaped(d, node.scope, node, value, 0);
                 }
                 if (node instanceof AST_SymbolCatch) {
                     node.definition().fixed = false;
@@ -623,10 +623,12 @@ merge(Compressor.prototype, {
             }
         }
 
-        function mark_escaped(d, node, value, level) {
+        function mark_escaped(d, scope, node, value, level) {
             var parent = tw.parent(level);
-            if (value instanceof AST_Constant) return;
-            if (level > 0 && value instanceof AST_Function) return;
+            if (value) {
+                if (value.is_constant()) return;
+                if (level > 0 && value.is_constant_expression(scope)) return;
+            }
             if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
                 || parent instanceof AST_Call && node !== parent.expression
                 || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
@@ -634,13 +636,13 @@ merge(Compressor.prototype, {
                 d.escaped = true;
                 return;
             } else if (parent instanceof AST_Array) {
-                mark_escaped(d, parent, parent, level + 1);
+                mark_escaped(d, scope, parent, parent, level + 1);
             } else if (parent instanceof AST_ObjectKeyVal && node === parent.value) {
                 var obj = tw.parent(level + 1);
-                mark_escaped(d, obj, obj, level + 2);
+                mark_escaped(d, scope, obj, obj, level + 2);
             } else if (parent instanceof AST_PropAccess && node === parent.expression) {
                 value = read_property(value, parent.property);
-                mark_escaped(d, parent, value, level + 1);
+                mark_escaped(d, scope, parent, value, level + 1);
                 if (value) return;
             }
             if (level == 0) d.direct_access = true;
diff --git a/test/compress/hoist_props.js b/test/compress/hoist_props.js
index 40d36ace..b2dd0270 100644
--- a/test/compress/hoist_props.js
+++ b/test/compress/hoist_props.js
@@ -500,3 +500,136 @@ issue_2473_4: {
     }
     expect_stdout: "1 2"
 }
+
+issue_2508_1: {
+    options = {
+        collapse_vars: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: [ 1 ],
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect: {
+        (function(x) {
+            console.log(x);
+        })([ 1 ]);
+    }
+    expect_stdout: true
+}
+
+issue_2508_2: {
+    options = {
+        collapse_vars: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: { b: 2 },
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect: {
+        (function(x) {
+            console.log(x);
+        })({ b: 2 });
+    }
+    expect_stdout: true
+}
+
+issue_2508_3: {
+    options = {
+        collapse_vars: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: [ o ],
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect: {
+        var o = {
+            a: [ o ],
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect_stdout: true
+}
+
+issue_2508_4: {
+    options = {
+        collapse_vars: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: { b: o },
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect: {
+        var o = {
+            a: { b: o },
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.a);
+    }
+    expect_stdout: true
+}
+
+issue_2508_5: {
+    options = {
+        collapse_vars: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            f: function(x) {
+                console.log(x);
+            }
+        };
+        o.f(o.f);
+    }
+    expect: {
+        var o_f = function(x) {
+            console.log(x);
+        };
+        o_f(o_f);
+    }
+    expect_stdout: true
+}
-- 
2.34.1