From c44cf0d0e62e24cadc08f50ae3d0039b30ca9982 Mon Sep 17 00:00:00 2001
From: Rich-Harris <richard.a.harris@gmail.com>
Date: Sat, 31 Oct 2015 22:36:40 -0400
Subject: [PATCH] exclude constructors that are known to be pure

---
 src/utils/testForSideEffects.js           | 14 ++++++++------
 test/form/side-effect-f/_config.js        |  6 ++++++
 test/form/side-effect-f/_expected/amd.js  |  7 +++++++
 test/form/side-effect-f/_expected/cjs.js  |  5 +++++
 test/form/side-effect-f/_expected/es6.js  |  3 +++
 test/form/side-effect-f/_expected/iife.js |  7 +++++++
 test/form/side-effect-f/_expected/umd.js  | 11 +++++++++++
 test/form/side-effect-f/main.js           |  8 ++++++++
 test/form/side-effect-g/_config.js        |  6 ++++++
 test/form/side-effect-g/_expected/amd.js  |  7 +++++++
 test/form/side-effect-g/_expected/cjs.js  |  5 +++++
 test/form/side-effect-g/_expected/es6.js  |  3 +++
 test/form/side-effect-g/_expected/iife.js |  7 +++++++
 test/form/side-effect-g/_expected/umd.js  | 11 +++++++++++
 test/form/side-effect-g/main.js           |  3 +++
 15 files changed, 97 insertions(+), 6 deletions(-)
 create mode 100644 test/form/side-effect-f/_config.js
 create mode 100644 test/form/side-effect-f/_expected/amd.js
 create mode 100644 test/form/side-effect-f/_expected/cjs.js
 create mode 100644 test/form/side-effect-f/_expected/es6.js
 create mode 100644 test/form/side-effect-f/_expected/iife.js
 create mode 100644 test/form/side-effect-f/_expected/umd.js
 create mode 100644 test/form/side-effect-f/main.js
 create mode 100644 test/form/side-effect-g/_config.js
 create mode 100644 test/form/side-effect-g/_expected/amd.js
 create mode 100644 test/form/side-effect-g/_expected/cjs.js
 create mode 100644 test/form/side-effect-g/_expected/es6.js
 create mode 100644 test/form/side-effect-g/_expected/iife.js
 create mode 100644 test/form/side-effect-g/_expected/umd.js
 create mode 100644 test/form/side-effect-g/main.js

diff --git a/src/utils/testForSideEffects.js b/src/utils/testForSideEffects.js
index aeb2413..1a42eba 100644
--- a/src/utils/testForSideEffects.js
+++ b/src/utils/testForSideEffects.js
@@ -6,8 +6,12 @@ import flatten from '../ast/flatten';
 
 let pureFunctions = {};
 [
-	// TODO add others to this list
-	'Object.keys'
+	// TODO add others to this list from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects
+	'Array', 'Array.isArray',
+
+	'Error', 'EvalError', 'InternalError', 'RangeError', 'ReferenceError', 'SyntaxError', 'TypeError', 'URIError',
+
+	'Object', 'Object.keys'
 ].forEach( name => pureFunctions[ name ] = true );
 
 export default function testForSideEffects ( node, scope, statement, strongDependencies, force ) {
@@ -31,13 +35,11 @@ export default function testForSideEffects ( node, scope, statement, strongDepen
 				}
 			}
 
-			// If this is a top-level call expression, or an assignment to a global,
-			// this statement will need to be marked
-			else if ( node.type === 'NewExpression' ) {
+			else if ( node.type === 'ThrowStatement' ) {
 				hasSideEffect = true;
 			}
 
-			else if ( node.type === 'CallExpression' ) {
+			else if ( node.type === 'CallExpression' || node.type === 'NewExpression' ) {
 				if ( node.callee.type === 'Identifier' ) {
 					const declaration = scope.findDeclaration( node.callee.name ) ||
 					                    statement.module.trace( node.callee.name );
diff --git a/test/form/side-effect-f/_config.js b/test/form/side-effect-f/_config.js
new file mode 100644
index 0000000..67f9fa4
--- /dev/null
+++ b/test/form/side-effect-f/_config.js
@@ -0,0 +1,6 @@
+module.exports = {
+	description: 'disregards side-effects that are contained within a function',
+	options: {
+		moduleName: 'myBundle'
+	}
+};
diff --git a/test/form/side-effect-f/_expected/amd.js b/test/form/side-effect-f/_expected/amd.js
new file mode 100644
index 0000000..37d2571
--- /dev/null
+++ b/test/form/side-effect-f/_expected/amd.js
@@ -0,0 +1,7 @@
+define(function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+});
diff --git a/test/form/side-effect-f/_expected/cjs.js b/test/form/side-effect-f/_expected/cjs.js
new file mode 100644
index 0000000..5a370cd
--- /dev/null
+++ b/test/form/side-effect-f/_expected/cjs.js
@@ -0,0 +1,5 @@
+'use strict';
+
+var main = 42;
+
+module.exports = main;
diff --git a/test/form/side-effect-f/_expected/es6.js b/test/form/side-effect-f/_expected/es6.js
new file mode 100644
index 0000000..d862de8
--- /dev/null
+++ b/test/form/side-effect-f/_expected/es6.js
@@ -0,0 +1,3 @@
+var main = 42;
+
+export default main;
diff --git a/test/form/side-effect-f/_expected/iife.js b/test/form/side-effect-f/_expected/iife.js
new file mode 100644
index 0000000..b7b15ee
--- /dev/null
+++ b/test/form/side-effect-f/_expected/iife.js
@@ -0,0 +1,7 @@
+var myBundle = (function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+})();
diff --git a/test/form/side-effect-f/_expected/umd.js b/test/form/side-effect-f/_expected/umd.js
new file mode 100644
index 0000000..b5aa08a
--- /dev/null
+++ b/test/form/side-effect-f/_expected/umd.js
@@ -0,0 +1,11 @@
+(function (global, factory) {
+	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
+	typeof define === 'function' && define.amd ? define(factory) :
+	global.myBundle = factory();
+}(this, function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+}));
diff --git a/test/form/side-effect-f/main.js b/test/form/side-effect-f/main.js
new file mode 100644
index 0000000..e75b2f3
--- /dev/null
+++ b/test/form/side-effect-f/main.js
@@ -0,0 +1,8 @@
+function foo () {
+	var a, b, c;
+	b = 1;
+}
+
+foo();
+
+export default 42;
diff --git a/test/form/side-effect-g/_config.js b/test/form/side-effect-g/_config.js
new file mode 100644
index 0000000..c821995
--- /dev/null
+++ b/test/form/side-effect-g/_config.js
@@ -0,0 +1,6 @@
+module.exports = {
+	description: 'excludes constructors that are known to be pure',
+	options: {
+		moduleName: 'myBundle'
+	}
+};
diff --git a/test/form/side-effect-g/_expected/amd.js b/test/form/side-effect-g/_expected/amd.js
new file mode 100644
index 0000000..37d2571
--- /dev/null
+++ b/test/form/side-effect-g/_expected/amd.js
@@ -0,0 +1,7 @@
+define(function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+});
diff --git a/test/form/side-effect-g/_expected/cjs.js b/test/form/side-effect-g/_expected/cjs.js
new file mode 100644
index 0000000..5a370cd
--- /dev/null
+++ b/test/form/side-effect-g/_expected/cjs.js
@@ -0,0 +1,5 @@
+'use strict';
+
+var main = 42;
+
+module.exports = main;
diff --git a/test/form/side-effect-g/_expected/es6.js b/test/form/side-effect-g/_expected/es6.js
new file mode 100644
index 0000000..d862de8
--- /dev/null
+++ b/test/form/side-effect-g/_expected/es6.js
@@ -0,0 +1,3 @@
+var main = 42;
+
+export default main;
diff --git a/test/form/side-effect-g/_expected/iife.js b/test/form/side-effect-g/_expected/iife.js
new file mode 100644
index 0000000..b7b15ee
--- /dev/null
+++ b/test/form/side-effect-g/_expected/iife.js
@@ -0,0 +1,7 @@
+var myBundle = (function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+})();
diff --git a/test/form/side-effect-g/_expected/umd.js b/test/form/side-effect-g/_expected/umd.js
new file mode 100644
index 0000000..b5aa08a
--- /dev/null
+++ b/test/form/side-effect-g/_expected/umd.js
@@ -0,0 +1,11 @@
+(function (global, factory) {
+	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
+	typeof define === 'function' && define.amd ? define(factory) :
+	global.myBundle = factory();
+}(this, function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+}));
diff --git a/test/form/side-effect-g/main.js b/test/form/side-effect-g/main.js
new file mode 100644
index 0000000..75d2cf5
--- /dev/null
+++ b/test/form/side-effect-g/main.js
@@ -0,0 +1,3 @@
+var err = new Error( 'this will be ignored' );
+
+export default 42;