From e1e0e94628ea63833cd0669b94ec3dd7c17c8c9e Mon Sep 17 00:00:00 2001
From: Jhen <developer@jhen.me>
Date: Sat, 6 May 2017 03:03:18 +0800
Subject: [PATCH 1/2] Add tests for collapse with circular reference

---
 .../transform-inline-consecutive-adds-test.js | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/packages/babel-plugin-transform-inline-consecutive-adds/__tests__/transform-inline-consecutive-adds-test.js b/packages/babel-plugin-transform-inline-consecutive-adds/__tests__/transform-inline-consecutive-adds-test.js
index b25b3894c..6ce2ce2b5 100644
--- a/packages/babel-plugin-transform-inline-consecutive-adds/__tests__/transform-inline-consecutive-adds-test.js
+++ b/packages/babel-plugin-transform-inline-consecutive-adds/__tests__/transform-inline-consecutive-adds-test.js
@@ -212,6 +212,16 @@ describe("transform-inline-consecutive-adds-plugin", () => {
     expect(transform(source)).toBe(source);
   });
 
+  it("should not collapse computed properties with circular reference", () => {
+    const source = unpad(
+      `
+      var foo = {};
+      foo.bar = foo;
+    `
+    );
+    expect(transform(source)).toBe(source);
+  });
+
   it("should collapse statements with multiple assignments", () => {
     const source = unpad(
       `
@@ -291,6 +301,16 @@ describe("transform-inline-consecutive-adds-plugin", () => {
     expect(transform(source)).toBe(expected);
   });
 
+  it("should not collapse statements for array-initialized sets with circular reference", () => {
+    const source = unpad(
+      `
+      var foo = new Set([1, 2]);
+      foo.add(foo);
+    `
+    );
+    expect(transform(source)).toBe(source);
+  });
+
   it("should collapse array property assignments", () => {
     const source = unpad(
       `
@@ -373,4 +393,14 @@ describe("transform-inline-consecutive-adds-plugin", () => {
     );
     expect(transform(source)).toBe(expected);
   });
+
+  it("should not collapse array property assignments if it is circular reference", () => {
+    const source = unpad(
+      `
+      var foo = [];
+      foo[2] = foo;
+    `
+    );
+    expect(transform(source)).toBe(source);
+  });
 });

From 201a8a8dabd9ffa428e25c297c7b6f9796d2c5ea Mon Sep 17 00:00:00 2001
From: Jhen <developer@jhen.me>
Date: Sat, 6 May 2017 21:51:19 +0800
Subject: [PATCH 2/2] Fix collapse with circular reference

---
 .../babel-plugin-transform-inline-consecutive-adds/src/index.js | 2 +-
 .../src/set-collapser.js                                        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/babel-plugin-transform-inline-consecutive-adds/src/index.js b/packages/babel-plugin-transform-inline-consecutive-adds/src/index.js
index 345d67854..0f9a5989e 100644
--- a/packages/babel-plugin-transform-inline-consecutive-adds/src/index.js
+++ b/packages/babel-plugin-transform-inline-consecutive-adds/src/index.js
@@ -142,7 +142,7 @@ function getContiguousStatementsAndExpressions(
 
 function getReferenceChecker(references) {
   // returns a function s.t. given an expr, returns true iff expr is an ancestor of a reference
-  return expr => references.some(r => r.isDescendant(expr));
+  return expr => references.some(r => r === expr || r.isDescendant(expr));
 }
 
 function tryUseCollapser(t, collapser, varDecl, topLevel, checkReference) {
diff --git a/packages/babel-plugin-transform-inline-consecutive-adds/src/set-collapser.js b/packages/babel-plugin-transform-inline-consecutive-adds/src/set-collapser.js
index 313cad3ff..c23bfe471 100644
--- a/packages/babel-plugin-transform-inline-consecutive-adds/src/set-collapser.js
+++ b/packages/babel-plugin-transform-inline-consecutive-adds/src/set-collapser.js
@@ -44,7 +44,7 @@ class SetCollapser extends Collapser {
       if (args.length !== 1) {
         return false;
       }
-      if (checkReference(args)) {
+      if (checkReference(args[0])) {
         return false;
       }
       return true;