Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

35 files changed, 1083 insertions, 0 deletions

diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-2gs-strict.js b/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-2gs-strict.js
new file mode 100644
index 0000000000..42a20db97e
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-2gs-strict.js
@@ -0,0 +1,19 @@
+// |reftest| error:SyntaxError
+'use strict';
+// Copyright (c) 2012 Ecma International.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+es5id: 11.4.5-2-2gs
+description: >
+    Strict Mode - SyntaxError is throw if the UnaryExpression operated
+    upon by a Prefix Decrement operator(--arguments)
+negative:
+  phase: parse
+  type: SyntaxError
+flags: [onlyStrict]
+---*/
+
+$DONOTEVALUATE();
+
+--arguments;
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-3-s.js b/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-3-s.js
new file mode 100644
index 0000000000..56033f721a
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/11.4.5-2-3-s.js
@@ -0,0 +1,16 @@
+// Copyright (c) 2012 Ecma International.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+es5id: 11.4.5-2-3-s
+description: SyntaxError is not thrown for --arguments[...]
+---*/
+
+function testcase() {
+        arguments[1] = 7;
+        --arguments[1];
+        assert.sameValue(arguments[1], 6, 'arguments[1]');
+    }
+testcase();
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T1.js
new file mode 100644
index 0000000000..5cd97ac2e5
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T1.js
@@ -0,0 +1,41 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x uses GetValue and PutValue
+es5id: 11.4.5_A2.1_T1
+description: Type(x) is Reference and GetBase(x) is not null
+---*/
+
+//CHECK#1
+var x = 1;
+if (--x !== 1 - 1) {
+  throw new Test262Error('#1: var x = 1; --x === 1 - 1. Actual: ' + (--x));
+} else {
+  if (x !== 1 - 1) {
+    throw new Test262Error('#1: var x = 1; --x; x === 1 - 1. Actual: ' + (x));
+  } 
+}
+
+//CHECK#2
+this.x = 1;
+if (--this.x !== 1 - 1) {
+  throw new Test262Error('#2: this.x = 1; --this.x === 1 - 1. Actual: ' + (--this.x));
+} else {
+  if (this.x !== 1 - 1) {
+    throw new Test262Error('#2: this.x = 1; --this.x; this.x === 1 - 1. Actual: ' + (this.x));
+  } 
+}
+
+//CHECK#3
+var object = new Object();
+object.prop = 1;
+if (--object.prop !== 1 - 1) {
+  throw new Test262Error('#3: var object = new Object(); object.prop = 1; --object.prop === 1 - 1. Actual: ' + (--object.prop));
+} else {
+  if (this.x !== 1 - 1) {
+    throw new Test262Error('#3: var object = new Object(); object.prop = 1; --object.prop; object.prop === 1 - 1. Actual: ' + (object.prop));
+  } 
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T2.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T2.js
new file mode 100644
index 0000000000..e57096133c
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.1_T2.js
@@ -0,0 +1,21 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x uses GetValue and PutValue
+es5id: 11.4.5_A2.1_T2
+description: If GetBase(x) is null, throw ReferenceError
+---*/
+
+//CHECK#1
+try {
+  --x;
+  throw new Test262Error('#1.1: --x throw ReferenceError. Actual: ' + (--x));  
+}
+catch (e) {
+  if ((e instanceof ReferenceError) !== true) {
+    throw new Test262Error('#1.2: --x throw ReferenceError. Actual: ' + (e));  
+  }
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.2_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.2_T1.js
new file mode 100644
index 0000000000..0f9d23139b
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A2.2_T1.js
@@ -0,0 +1,104 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x uses [[Default Value]]
+es5id: 11.4.5_A2.2_T1
+description: If Type(value) is Object, evaluate ToPrimitive(value, Number)
+---*/
+
+//CHECK#1
+var object = {valueOf: function() {return 1}};
+if (--object !== 1 - 1) {
+  throw new Test262Error('#1: var object = {valueOf: function() {return 1}}; --object === 1 - 1. Actual: ' + (--object));
+} else {
+  if (object !== 1 - 1) {
+    throw new Test262Error('#1: var object = {valueOf: function() {return 1}}; --object; object === 1 - 1. Actual: ' + (object));
+  }
+}
+
+//CHECK#2
+var object = {valueOf: function() {return 1}, toString: function() {return 0}};
+if (--object !== 1 - 1) {
+  throw new Test262Error('#2: var object = {valueOf: function() {return 1}, toString: function() {return 0}}; --object === 1 - 1. Actual: ' + (--object));
+} else {
+  if (object !== 1 - 1) {
+    throw new Test262Error('#2: var object = {valueOf: function() {return 1}, toString: function() {return 0}}; --object; object === 1 - 1. Actual: ' + (object));
+  }
+}
+
+//CHECK#3
+var object = {valueOf: function() {return 1}, toString: function() {return {}}};
+if (--object !== 1 - 1) {
+  throw new Test262Error('#3: var object = {valueOf: function() {return 1}, toString: function() {return {}}}; --object === 1 - 1. Actual: ' + (--object));
+} else {
+  if (object !== 1 - 1) {
+    throw new Test262Error('#3: var object = {valueOf: function() {return 1}, toString: function() {return {}}}; --object; object === 1 - 1. Actual: ' + (object));
+  }
+}
+
+//CHECK#4
+try {
+  var object = {valueOf: function() {return 1}, toString: function() {throw "error"}};
+  if (--object !== 1 - 1) {
+    throw new Test262Error('#4.1: var object = {valueOf: function() {return 1}, toString: function() {throw "error"}}; --object === 1 - 1. Actual: ' + (--object));
+  } else {
+    if (object !== 1 - 1) {
+      throw new Test262Error('#4.1: var object = {valueOf: function() {return 1}, toString: function() {throw "error"}}; --object; object === 1 - 1. Actual: ' + (object));
+    }
+  }
+}
+catch (e) {
+  if (e === "error") {
+    throw new Test262Error('#4.2: var object = {valueOf: function() {return 1}, toString: function() {throw "error"}}; --object not throw "error"');
+  } else {
+    throw new Test262Error('#4.3: var object = {valueOf: function() {return 1}, toString: function() {throw "error"}}; --object not throw Error. Actual: ' + (e));
+  }
+}
+
+//CHECK#5
+var object = {toString: function() {return 1}};
+if (--object !== 1 - 1) {
+  throw new Test262Error('#5.1: var object = {toString: function() {return 1}}; --object === 1 - 1. Actual: ' + (--object));
+} else {
+  if (object !== 1 - 1) {
+    throw new Test262Error('#5.2: var object = {toString: function() {return 1}}; --object; object === 1 - 1. Actual: ' + (object));
+  }
+}
+
+
+//CHECK#6
+var object = {valueOf: function() {return {}}, toString: function() {return 1}}
+if (--object !== 1 - 1) {
+  throw new Test262Error('#6.1: var object = {valueOf: function() {return {}}, toString: function() {return 1}}; --object === 1 - 1. Actual: ' + (--object));
+} else {
+  if (object !== 1 - 1) {
+    throw new Test262Error('#6.2: var object = {valueOf: function() {return {}}, toString: function() {return 1}}; --object; object === 1 - 1. Actual: ' + (object));
+  }
+}
+
+//CHECK#7
+try {
+  var object = {valueOf: function() {throw "error"}, toString: function() {return 1}};
+  --object;
+  throw new Test262Error('#7.1: var object = {valueOf: function() {throw "error"}, toString: function() {return 1}}; --object throw "error". Actual: ' + (--object));
+}  
+catch (e) {
+  if (e !== "error") {
+    throw new Test262Error('#7.2: var object = {valueOf: function() {throw "error"}, toString: function() {return 1}}; --object throw "error". Actual: ' + (e));
+  } 
+}
+
+//CHECK#8
+try {
+  var object = {valueOf: function() {return {}}, toString: function() {return {}}};
+  --object;
+  throw new Test262Error('#8.1: var object = {valueOf: function() {return {}}, toString: function() {return {}}}; --object throw TypeError. Actual: ' + (--object));
+}  
+catch (e) {
+  if ((e instanceof TypeError) !== true) {
+    throw new Test262Error('#8.2: var object = {valueOf: function() {return {}}, toString: function() {return {}}}; --object throw TypeError. Actual: ' + (e));
+  } 
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T1.js
new file mode 100644
index 0000000000..6ff5479bd0
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T1.js
@@ -0,0 +1,24 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns x = ToNumber(x) - 1
+es5id: 11.4.5_A3_T1
+description: Type(x) is boolean primitive or Boolean object
+---*/
+
+//CHECK#1
+var x = true; 
+--x;
+if (x !== 1 - 1) {
+  throw new Test262Error('#1: var x = true; --x; x === 1 - 1. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = new Boolean(false); 
+--x;
+if (x !== 0 - 1) {
+  throw new Test262Error('#2: var x = new Boolean(false); --x; x === 0 - 1. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T2.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T2.js
new file mode 100644
index 0000000000..a71845fef6
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T2.js
@@ -0,0 +1,24 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns x = ToNumber(x) - 1
+es5id: 11.4.5_A3_T2
+description: Type(x) is number primitive or Number object
+---*/
+
+//CHECK#1
+var x = 0.1; 
+--x;
+if (x !== 0.1 - 1) {
+  throw new Test262Error('#1: var x = 0.1; --x; x === 0.1 - 1. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = new Number(-1.1); 
+--x;
+if (x !== -1.1 - 1) {
+  throw new Test262Error('#2: var x = new Number(-1.1); --x; x === -1.1 - 1. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T3.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T3.js
new file mode 100644
index 0000000000..d9d6a93b06
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T3.js
@@ -0,0 +1,31 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns x = ToNumber(x) - 1
+es5id: 11.4.5_A3_T3
+description: Type(x) is primitive string or String object
+---*/
+
+//CHECK#1
+var x = "1"; 
+--x;
+if (x !== 1 - 1) {
+  throw new Test262Error('#1: var x = "1"; --x; x === 1 - 1. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = "x"; 
+--x; 
+if (isNaN(x) !== true) {
+  throw new Test262Error('#2: var x = "x"; --x; x === Not-a-Number. Actual: ' + (x));
+}
+
+//CHECK#3
+var x = new Number("-1"); 
+--x;
+if (x !== -1 - 1) {
+  throw new Test262Error('#3: var x = new String("-1"); --x; x === -1 - 1. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T4.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T4.js
new file mode 100644
index 0000000000..f2b894736b
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T4.js
@@ -0,0 +1,24 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns x = ToNumber(x) - 1
+es5id: 11.4.5_A3_T4
+description: Type(x) is undefined or null
+---*/
+
+//CHECK#1
+var x; 
+--x;
+if (isNaN(x) !== true) {
+  throw new Test262Error('#1: var x; --x; x === Not-a-Number. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = null; 
+--x;
+if (x !== -1) {
+  throw new Test262Error('#2: var x = null; --x; x === -1. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T5.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T5.js
new file mode 100644
index 0000000000..0b7614444c
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A3_T5.js
@@ -0,0 +1,24 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns x = ToNumber(x) - 1
+es5id: 11.4.5_A3_T5
+description: Type(x) is Object object or Function object
+---*/
+
+//CHECK#1
+var x = {}; 
+--x; 
+if (isNaN(x) !== true) {
+  throw new Test262Error('#1: var x = {}; --x; x === Not-a-Number. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = function(){return 1}; 
+--x; 
+if (isNaN(x) !== true) {
+  throw new Test262Error('#2: var x = function(){return 1}; --x; x === Not-a-Number. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T1.js
new file mode 100644
index 0000000000..7cb3216ad8
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T1.js
@@ -0,0 +1,22 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns ToNumber(x) - 1
+es5id: 11.4.5_A4_T1
+description: Type(x) is boolean primitive or Boolean object
+---*/
+
+//CHECK#1
+var x = true;
+if (--x !== 1 - 1) {
+  throw new Test262Error('#1: var x = true; --x === 1 - 1. Actual: ' + (--x));
+}
+
+//CHECK#2
+var x = new Boolean(false);
+if (--x !== 0 - 1) {
+  throw new Test262Error('#2: var x = new Boolean(false); --x === 0 - 1. Actual: ' + (--x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T2.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T2.js
new file mode 100644
index 0000000000..6f79668e10
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T2.js
@@ -0,0 +1,22 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns ToNumber(x) - 1
+es5id: 11.4.5_A4_T2
+description: Type(x) is number primitive or Number object
+---*/
+
+//CHECK#1
+var x = 0.1;
+if (--x !== 0.1 - 1) {
+  throw new Test262Error('#1: var x = 0.1; --x === 0.1 - 1. Actual: ' + (--x));
+}
+
+//CHECK#2
+var x = new Number(-1.1);
+if (--x !== -1.1 - 1) {
+  throw new Test262Error('#2: var x = new Number(-1.1); --x === -1.1- 1. Actual: ' + (--x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T3.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T3.js
new file mode 100644
index 0000000000..a7add2c03b
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T3.js
@@ -0,0 +1,28 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns ToNumber(x) - 1
+es5id: 11.4.5_A4_T3
+description: Type(x) is string primitive or String object
+---*/
+
+//CHECK#1
+var x = "1";
+if (--x !== 1 - 1) {
+  throw new Test262Error('#1: var x = "1"; --x === 1 - 1. Actual: ' + (--x));
+}
+
+//CHECK#2
+var x = "x";
+if (isNaN(--x) !== true) {
+  throw new Test262Error('#2: var x = "x"; --x === Not-a-Number. Actual: ' + (--x));
+}
+
+//CHECK#3
+var x = new String("-1"); 
+if (--x !== -1 - 1) {
+  throw new Test262Error('#3: var x = new String("-1"); --x === -1 - 1. Actual: ' + (--x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T4.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T4.js
new file mode 100644
index 0000000000..cda8745456
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T4.js
@@ -0,0 +1,22 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns ToNumber(x) - 1
+es5id: 11.4.5_A4_T4
+description: Type(x) is undefined or null
+---*/
+
+//CHECK#1
+var x;
+if (isNaN(--x) !== true) {
+  throw new Test262Error('#1: var x; --x; x === Not-a-Number. Actual: ' + (x));
+}
+
+//CHECK#2
+var x = null;
+if (--x !== -1) {
+  throw new Test262Error('#2: var x = null; --x === -1. Actual: ' + (--x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T5.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T5.js
new file mode 100644
index 0000000000..6d631d188e
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A4_T5.js
@@ -0,0 +1,22 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x returns ToNumber(x) - 1
+es5id: 11.4.5_A4_T5
+description: Type(x) is Object object or Function object
+---*/
+
+//CHECK#1
+var x = {}; 
+if (isNaN(--x) !== true) {
+  throw new Test262Error('#1: var x = {}; --x === Not-a-Number. Actual: ' + (--x));
+}
+
+//CHECK#2
+var x = function(){return 1}; 
+if (isNaN(--x) !== true) {
+  throw new Test262Error('#2: var x = function(){return 1}; --x === Not-a-Number. Actual: ' + (--x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T1.js
new file mode 100644
index 0000000000..3ffed09bb1
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T1.js
@@ -0,0 +1,38 @@
+// Copyright (C) 2014 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x calls PutValue(lhs, newValue)
+es5id: S11.4.5_A5_T1
+description: >
+    Evaluating LeftHandSideExpression lhs returns Reference type; Reference
+    base value is an environment record and environment record kind is
+    object environment record. PutValue(lhs, newValue) uses the initially
+    created Reference even if the environment binding is no longer present.
+    Binding in surrounding function environment record is not changed.
+flags: [noStrict]
+---*/
+
+function testFunction() {
+  var x = 0;
+  var scope = {
+    get x() {
+      delete this.x;
+      return 2;
+    }
+  };
+
+  with (scope) {
+    --x;
+  }
+
+  if (scope.x !== 1) {
+    throw new Test262Error('#1: scope.x === 1. Actual: ' + (scope.x));
+  }
+  if (x !== 0) {
+    throw new Test262Error('#2: x === 0. Actual: ' + (x));
+  }
+}
+testFunction();
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T2.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T2.js
new file mode 100644
index 0000000000..d8a9f39fee
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T2.js
@@ -0,0 +1,35 @@
+// Copyright (C) 2014 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x calls PutValue(lhs, newValue)
+es5id: S11.4.5_A5_T2
+description: >
+    Evaluating LeftHandSideExpression lhs returns Reference type; Reference
+    base value is an environment record and environment record kind is
+    object environment record. PutValue(lhs, newValue) uses the initially
+    created Reference even if the environment binding is no longer present.
+    Binding in surrounding global environment record is not changed.
+flags: [noStrict]
+---*/
+
+var x = 0;
+var scope = {
+  get x() {
+    delete this.x;
+    return 2;
+  }
+};
+
+with (scope) {
+  --x;
+}
+
+if (scope.x !== 1) {
+  throw new Test262Error('#1: scope.x === 1. Actual: ' + (scope.x));
+}
+if (x !== 0) {
+  throw new Test262Error('#2: x === 0. Actual: ' + (x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T3.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T3.js
new file mode 100644
index 0000000000..6c02d3a490
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A5_T3.js
@@ -0,0 +1,39 @@
+// Copyright (C) 2014 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x calls PutValue(lhs, newValue)
+es5id: S11.4.5_A5_T3
+description: >
+    Evaluating LeftHandSideExpression lhs returns Reference type; Reference
+    base value is an environment record and environment record kind is
+    object environment record. PutValue(lhs, newValue) uses the initially
+    created Reference even if the environment binding is no longer present.
+    Binding in surrounding object environment record is not changed.
+flags: [noStrict]
+---*/
+
+var outerScope = {
+  x: 0
+};
+var innerScope = {
+  get x() {
+    delete this.x;
+    return 2;
+  }
+};
+
+with (outerScope) {
+  with (innerScope) {
+    --x;
+  }
+}
+
+if (innerScope.x !== 1) {
+  throw new Test262Error('#1: innerScope.x === 1. Actual: ' + (innerScope.x));
+}
+if (outerScope.x !== 0) {
+  throw new Test262Error('#2: outerScope.x === 0. Actual: ' + (outerScope.x));
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T1.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T1.js
new file mode 100644
index 0000000000..149a49a0a1
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T1.js
@@ -0,0 +1,33 @@
+// Copyright (C) 2015 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x evaluates its reference expression once.
+description: >
+    The operand expression is evaluated exactly once. Operand expression is
+    MemberExpression: base[prop]. base is the null value.
+---*/
+
+function DummyError() { }
+
+assert.throws(DummyError, function() {
+  var base = null;
+  var prop = function() {
+    throw new DummyError();
+  };
+
+  --base[prop()];
+});
+
+assert.throws(TypeError, function() {
+  var base = null;
+  var prop = {
+    toString: function() {
+      throw new Test262Error("property key evaluated");
+    }
+  };
+
+  --base[prop];
+});
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T2.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T2.js
new file mode 100644
index 0000000000..09495dee06
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T2.js
@@ -0,0 +1,33 @@
+// Copyright (C) 2015 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x evaluates its reference expression once.
+description: >
+    The operand expression is evaluated exactly once. Operand expression is
+    MemberExpression: base[prop]. base is the undefined value.
+---*/
+
+function DummyError() { }
+
+assert.throws(DummyError, function() {
+  var base = undefined;
+  var prop = function() {
+    throw new DummyError();
+  };
+
+  --base[prop()];
+});
+
+assert.throws(TypeError, function() {
+  var base = undefined;
+  var prop = {
+    toString: function() {
+      throw new Test262Error("property key evaluated");
+    }
+  };
+
+  --base[prop];
+});
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T3.js b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T3.js
new file mode 100644
index 0000000000..b274872680
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/S11.4.5_A6_T3.js
@@ -0,0 +1,24 @@
+// Copyright (C) 2015 André Bargull. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+info: Operator --x evaluates its reference expression once.
+description: >
+    The operand expression is evaluated exactly once. Operand expression is
+    MemberExpression: base[prop]. ToPropertyKey(prop) is not called multiple
+    times.
+---*/
+
+var propKeyEvaluated = false;
+var base = {};
+var prop = {
+  toString: function() {
+    assert(!propKeyEvaluated);
+    propKeyEvaluated = true;
+    return 1;
+  }
+};
+
+--base[prop];
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/arguments-nostrict.js b/js/src/tests/test262/language/expressions/prefix-decrement/arguments-nostrict.js
new file mode 100644
index 0000000000..b82439c517
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/arguments-nostrict.js
@@ -0,0 +1,27 @@
+// Copyright (c) 2018 Rick Waldron.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-update-expressions
+description: >
+  In non-strict code, "--arguments" does not produce an early error.
+info: |
+  sec-identifiers-static-semantics-assignmenttargettype
+
+    1. If this IdentifierReference is contained in strict mode code and StringValue of Identifier is "eval" or  "arguments", return strict.
+    2. Return simple.
+
+  sec-update-expressions-static-semantics-early-errors
+
+    UpdateExpression -- UnaryExpression
+
+    It is an early Reference Error if AssignmentTargetType of UnaryExpression is invalid.
+    It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict.
+flags: [noStrict]
+---*/
+
+if (false) {
+  --arguments;
+}
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/arguments-strict.js b/js/src/tests/test262/language/expressions/prefix-decrement/arguments-strict.js
new file mode 100644
index 0000000000..363377c705
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/arguments-strict.js
@@ -0,0 +1,28 @@
+// |reftest| error:SyntaxError
+'use strict';
+// Copyright (c) 2012 Ecma International.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-update-expressions
+description: >
+  It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict. (arguments)
+info: |
+  sec-identifiers-static-semantics-assignmenttargettype
+
+    If this IdentifierReference is contained in strict mode code and StringValue of Identifier is "eval" or  "arguments", return strict.
+
+  sec-update-expressions-static-semantics-early-errors
+
+    UpdateExpression: -- UnaryExpression
+
+    It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict.
+flags: [onlyStrict]
+negative:
+  phase: parse
+  type: SyntaxError
+---*/
+
+$DONOTEVALUATE();
+
+--arguments;
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/bigint.js b/js/src/tests/test262/language/expressions/prefix-decrement/bigint.js
new file mode 100644
index 0000000000..39897ecb13
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/bigint.js
@@ -0,0 +1,64 @@
+// Copyright (C) 2017 Josh Wolfe. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Prefix decrement for references to BigInt values
+esid: sec-prefix-decrement-operator-runtime-semantics-evaluation
+info: |
+  1. Let expr be the result of evaluating UnaryExpression.
+  2. Let oldValue be ? ToNumeric(? GetValue(expr)).
+  3. Let newValue be ? Type(oldvalue)::subtract(oldValue, Type(oldValue)::unit).
+  4. Perform ? PutValue(expr, newValue).
+  5. Return newValue.
+features: [BigInt]
+---*/
+
+var x = 1n;
+assert.sameValue(--x, 0n, "var x = 1n; --x === 0n");
+assert.sameValue(x, 0n, "var x = 1n; --x; x === 0n");
+
+var x = 0n;
+assert.sameValue(--x, -1n, "var x = 0n; --x === -1n");
+assert.sameValue(x, -1n, "var x = 0n; --x; x === -1n");
+
+var x = 123457n;
+assert.sameValue(--x, 123456n, "var x = 123457n; --x === 123456n");
+assert.sameValue(x, 123456n, "var x = 123457n; --x; x === 123456n");
+
+var x = -123456n;
+assert.sameValue(--x, -123457n, "var x = -123456n; --x === -123457n");
+assert.sameValue(x, -123457n, "var x = -123456n; --x; x === -123457n");
+
+var x = 0x1fffffffffffff01n;
+assert.sameValue(--x, 0x1fffffffffffff00n, "var x = 0x1fffffffffffff01n; --x === 0x1fffffffffffff00n");
+assert.sameValue(x, 0x1fffffffffffff00n, "var x = 0x1fffffffffffff01n; --x; x === 0x1fffffffffffff00n");
+
+var x = -0x1fffffffffffff00n;
+assert.sameValue(--x, -0x1fffffffffffff01n, "var x = -0x1fffffffffffff00n; --x === -0x1fffffffffffff01n");
+assert.sameValue(x, -0x1fffffffffffff01n, "var x = -0x1fffffffffffff00n; --x; x === -0x1fffffffffffff01n");
+
+var x = {y:1n};
+assert.sameValue(--x.y, 0n, "var x = {y:1n}; --x.y === 0n");
+assert.sameValue(x.y, 0n, "var x = {y:1n}; --x.y; x.y === 0n");
+
+var x = {y:{z:1n}};
+assert.sameValue(--x.y.z, 0n, "var x = {y:{z:1n}}; --x.y.z === 0n");
+assert.sameValue(x.y.z, 0n, "var x = {y:{z:1n}}; --x.y.z; x.y.z === 0n");
+
+var x = [1n];
+assert.sameValue(--x[0], 0n, "var x = [1n]; --x[0] === 0n");
+assert.sameValue(x[0], 0n, "var x = [1n]; --x[0]; x[0] === 0n");
+
+var x = [null, [null, null, 1n]];
+assert.sameValue(--x[1][2], 0n, "var x = [null, [null, null, 1n]]; --x[1][2] === 0n");
+assert.sameValue(x[1][2], 0n, "var x = [null, [null, null, 1n]]; --x[1][2]; x[1][2] === 0n");
+
+var x = {y:[1n]};
+assert.sameValue(--x.y[0], 0n, "var x = {y:[1n]}; --x.y[0] === 0n");
+assert.sameValue(x.y[0], 0n, "var x = {y:[1n]}; --x.y[0]; x.y[0] === 0n");
+
+var x = [{z:1n}];
+assert.sameValue(--x[0].z, 0n, "var x = [{z:1n}]; --x[0].z === 0n");
+assert.sameValue(x[0].z, 0n, "var x = [{z:1n}]; --x[0].z; x[0].z === 0n");
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/browser.js b/js/src/tests/test262/language/expressions/prefix-decrement/browser.js
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/browser.js
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/eval-nostrict.js b/js/src/tests/test262/language/expressions/prefix-decrement/eval-nostrict.js
new file mode 100644
index 0000000000..3eff3119e7
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/eval-nostrict.js
@@ -0,0 +1,25 @@
+// Copyright (c) 2018 Rick Waldron.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-update-expressions
+description: >
+  In non-strict code, "--eval" does not produce an early error.
+info: |
+  sec-identifiers-static-semantics-assignmenttargettype
+
+    1. If this IdentifierReference is contained in strict mode code and StringValue of Identifier is "eval" or  "arguments", return strict.
+    2. Return simple.
+
+  sec-update-expressions-static-semantics-early-errors
+
+    UpdateExpression -- UnaryExpression
+
+    It is an early Reference Error if AssignmentTargetType of UnaryExpression is invalid.
+    It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict.
+flags: [noStrict]
+---*/
+
+--eval;
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/eval-strict.js b/js/src/tests/test262/language/expressions/prefix-decrement/eval-strict.js
new file mode 100644
index 0000000000..203b5ac94a
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/eval-strict.js
@@ -0,0 +1,28 @@
+// |reftest| error:SyntaxError
+'use strict';
+// Copyright (c) 2012 Ecma International.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-update-expressions
+description: >
+  It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict. (eval)
+info: |
+  sec-identifiers-static-semantics-assignmenttargettype
+
+    If this IdentifierReference is contained in strict mode code and StringValue of Identifier is "eval" or  "arguments", return strict.
+
+  sec-update-expressions-static-semantics-early-errors
+
+    UpdateExpression: -- UnaryExpression
+
+    It is an early Syntax Error if AssignmentTargetType of UnaryExpression is strict.
+flags: [onlyStrict]
+negative:
+  phase: parse
+  type: SyntaxError
+---*/
+
+$DONOTEVALUATE();
+
+--eval;
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue--1.js b/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue--1.js
new file mode 100644
index 0000000000..ee57f0c376
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue--1.js
@@ -0,0 +1,41 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-object-environment-records-setmutablebinding-n-v-s
+description: >
+  Operator --x calls PutValue(lhs, newValue) (formerly S11.4.5_A5_T5)
+info: |
+  The concrete Environment Record method SetMutableBinding for object Environment
+  Records attempts to set the value of the Environment Record's associated binding
+  object's property whose name is the value of the argument N to the value of argument V.
+  A property named N normally already exists but if it does not or is not currently writable,
+  error handling is determined by the value of the Boolean argument S.
+
+  Let stillExists be ? HasProperty(bindings, N).
+  If stillExists is false and S is true, throw a ReferenceError exception.
+flags: [noStrict]
+---*/
+var count = 0;
+Object.defineProperty(this, "x", {
+  configurable: true,
+  get: function() {
+    delete this.x;
+    return 2;
+  }
+});
+
+(function() {
+  "use strict";
+  assert.throws(ReferenceError, () => {
+    count++;
+    --x;
+    count++;
+  });
+  count++;
+})();
+
+assert.sameValue(count, 2);
+assert(!('x' in this));
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue-.js b/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue-.js
new file mode 100644
index 0000000000..4c76ae6ff6
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/operator-prefix-decrement-x-calls-putvalue-lhs-newvalue-.js
@@ -0,0 +1,42 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-object-environment-records-setmutablebinding-n-v-s
+description: >
+  Operator --x calls PutValue(lhs, newValue) (formerly S11.4.5_A5_T4)
+info: |
+  The concrete Environment Record method SetMutableBinding for object Environment
+  Records attempts to set the value of the Environment Record's associated binding
+  object's property whose name is the value of the argument N to the value of argument V.
+  A property named N normally already exists but if it does not or is not currently writable,
+  error handling is determined by the value of the Boolean argument S.
+
+  Let stillExists be ? HasProperty(bindings, N).
+  If stillExists is false and S is true, throw a ReferenceError exception.
+flags: [noStrict]
+---*/
+var count = 0;
+var scope = {
+  get x() {
+    delete this.x;
+    return 2;
+  }
+};
+
+with (scope) {
+  (function() {
+    "use strict";
+    assert.throws(ReferenceError, () => {
+      count++;
+      --x;
+      count++;
+    });
+    count++;
+  })();
+}
+
+assert.sameValue(count, 2);
+assert(!('x' in scope));
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/shell.js b/js/src/tests/test262/language/expressions/prefix-decrement/shell.js
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/shell.js
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-id.js b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-id.js
new file mode 100644
index 0000000000..56a929c2cc
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-id.js
@@ -0,0 +1,31 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-unary-operators-static-semantics-early-errors
+es6id: 12.5.1
+es5id: 11.1.6_A3_T5
+description: Applied to a "covered" IdentifierReference
+info: |
+  UnaryExpression :
+    ++ UnaryExpression
+    -- UnaryExpression
+
+  - It is an early Reference Error if IsValidSimpleAssignmentTarget of
+    UnaryExpression is false.
+
+  Static Semantics: IsValidSimpleAssignmentTarget
+
+  IdentifierReference : Identifier
+
+  1. If this IdentifierReference is contained in strict mode code and
+     StringValue of Identifier is "eval" or "arguments", return false.
+  2. Return true.
+---*/
+
+var y = 1;
+
+--(y);
+
+assert.sameValue(y, 0);
+
+reportCompare(0, 0);
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-newtarget.js b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-newtarget.js
new file mode 100644
index 0000000000..f976891363
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-newtarget.js
@@ -0,0 +1,32 @@
+// |reftest| error:SyntaxError
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-update-expressions-static-semantics-early-errors
+description: Applied to a "covered" new.target
+info: |
+  UnaryExpression :
+    ++ UnaryExpression
+    -- UnaryExpression
+
+  - It is an early Syntax Error if IsValidSimpleAssignmentTarget of
+    UnaryExpression is invalid or strict.
+
+  12.3.1.6 Static Semantics: AssignmentTargetType
+
+  NewTarget:
+
+  new.target
+
+  1. Return invalid.
+negative:
+  phase: parse
+  type: SyntaxError
+features: [new.target]
+---*/
+
+$DONOTEVALUATE();
+
+function f() {
+  --(new.target);
+}
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-yieldexpr.js b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-yieldexpr.js
new file mode 100644
index 0000000000..92cac869d1
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/target-cover-yieldexpr.js
@@ -0,0 +1,35 @@
+// |reftest| error:SyntaxError
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-update-expressions-static-semantics-early-errors
+description: Applied to a "covered" YieldExpression
+info: |
+  UnaryExpression :
+    ++ UnaryExpression
+    -- UnaryExpression
+
+  - It is an early Syntax Error if IsValidSimpleAssignmentTarget of
+    UnaryExpression is invalid or strict.
+
+  12.15.3 Static Semantics: AssignmentTargetType
+
+  AssignmentExpression:
+    YieldExpression
+    ArrowFunction
+    AsyncArrowFunction
+    LeftHandSideExpression = AssignmentExpression
+    LeftHandSideExpression AssignmentOperator AssignmentExpression
+
+  1. Return invalid.
+features: [generators]
+negative:
+  phase: parse
+  type: SyntaxError
+---*/
+
+$DONOTEVALUATE();
+
+function* g() {
+  --(yield);
+}
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/target-newtarget.js b/js/src/tests/test262/language/expressions/prefix-decrement/target-newtarget.js
new file mode 100644
index 0000000000..dd97e59f8d
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/target-newtarget.js
@@ -0,0 +1,32 @@
+// |reftest| error:SyntaxError
+// Copyright (C) 2016 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-update-expressions-static-semantics-early-errors
+description: Applied to new.target
+info: |
+  UnaryExpression :
+    ++ UnaryExpression
+    -- UnaryExpression
+
+  - It is an early Syntax Error if IsValidSimpleAssignmentTarget of
+    UnaryExpression is invalid or strict.
+
+  12.3.1.6 Static Semantics: AssignmentTargetType
+
+  NewTarget:
+
+  new.target
+
+  1. Return invalid.
+negative:
+  phase: parse
+  type: SyntaxError
+features: [new.target]
+---*/
+
+$DONOTEVALUATE();
+
+function f() {
+  --new.target;
+}
diff --git a/js/src/tests/test262/language/expressions/prefix-decrement/whitespace.js b/js/src/tests/test262/language/expressions/prefix-decrement/whitespace.js
new file mode 100644
index 0000000000..f7a38319c7
--- /dev/null
+++ b/js/src/tests/test262/language/expressions/prefix-decrement/whitespace.js
@@ -0,0 +1,52 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: |
+    White Space and Line Terminator between "--" and UnaryExpression are
+    allowed
+es5id: 11.4.5_A1
+esid: sec-prefix-decrement-operator
+---*/
+
+var x = 0;
+
+assert.sameValue(--	x, -1, 'U+0009 (expression)');
+assert.sameValue(x, -1, 'U+0009 (side effect)');
+
+assert.sameValue(--x, -2, 'U+000B (expression)');
+assert.sameValue(x, -2, 'U+000B (side effect)');
+
+assert.sameValue(--x, -3, 'U+000C (expression)');
+assert.sameValue(x, -3, 'U+000C (side effect)');
+
+assert.sameValue(-- x, -4, 'U+0020 (expression)');
+assert.sameValue(x, -4, 'U+0020 (side effect)');
+
+assert.sameValue(-- x, -5, 'U+00A0 (expression)');
+assert.sameValue(x, -5, 'U+00A0 (side effect)');
+
+assert.sameValue(--
+x, -6, 'U+000A (expression)');
+assert.sameValue(x, -6, 'U+000A (side effect)');
+
+assert.sameValue(--
x, -7, 'U+000D (expression)');
+assert.sameValue(x, -7, 'U+000D (side effect)');
+
+assert.sameValue(--
x, -8, 'U+2028 (expression)');
+assert.sameValue(x, -8, 'U+2028 (side effect)');
+
+assert.sameValue(--
x, -9, 'U+2029 (expression)');
+assert.sameValue(x, -9, 'U+2029 (side effect)');
+
+assert.sameValue(
+  --	  
+


x,
+  -10,
+  'U+0009U+000BU+000CU+0020U+00A0U+000AU+000DU+2028U+2029 (expression)'
+);
+assert.sameValue(
+  x, -10, 'U+0009U+000BU+000CU+0020U+00A0U+000AU+000DU+2028U+2029 (side effect)'
+);
+
+reportCompare(0, 0);