diff --git a/test/classes.js b/test/classes.js
deleted file mode 100644
index 3dc175bc0d..0000000000
--- a/test/classes.js
+++ /dev/null
@@ -1,51 +0,0 @@
-var transform = require("../lib/6to5/transform");
-var assert    = require("assert");
-
-suite("classes", function () {
-  test("no calling super properties", function () {
-    assert.throws(function () {
-      transform.test([
-        "class Test extends Foo {",
-        "  constructor() {",
-        "    super.test.whatever();",
-        "  }",
-        "}"
-      ]);
-    }, /cannot access super properties/);
-  });
-
-  test("no accessing super properties", function () {
-    assert.throws(function () {
-      transform.test([
-        "class Test extends Foo {",
-        "  constructor() {",
-        "    super.test.whatever;",
-        "  }",
-        "}"
-      ]);
-    }, /cannot access super properties/);
-  });
-
-  test("accessing super without having one", function () {
-    assert.throws(function () {
-      transform.test([
-        "class Test {",
-        "  constructor() {",
-        "    super();",
-        "  }",
-        "}"
-      ]);
-    }, /cannot access super as this class has none/);
-  });
-
-  test("defining constructor as a mutator", function () {
-    assert.throws(function () {
-      transform.test([
-        "class Test {",
-        "  get constructor() {",
-        "  }",
-        "}"
-      ]);
-    }, /unknown kind for constructor method/);
-  });
-});
diff --git a/test/errors.js b/test/errors.js
deleted file mode 100644
index e4ccd0ef8d..0000000000
--- a/test/errors.js
+++ /dev/null
@@ -1,14 +0,0 @@
-var transform = require("../lib/6to5/transform");
-var assert    = require("assert");
-
-suite("errors", function () {
-  test("syntax", function () {
-    assert.throws(function () {
-      transform.test([
-        "arr.map(function () {",
-        "  return $@!@#;",
-        "});"
-      ]);
-    }, /Error: test: Line 2: Unexpected token ILLEGAL/);
-  });
-});
diff --git a/test/fixtures/block-binding/ignore-root/expected.js b/test/fixtures/block-binding/ignore-root/expected.js
deleted file mode 100644
index f17c6fc26d..0000000000
--- a/test/fixtures/block-binding/ignore-root/expected.js
+++ /dev/null
@@ -1,5 +0,0 @@
-var arr = [
-  1,
-  2,
-  3
-];
diff --git a/test/fixtures/block-binding/ignore-root/actual.js b/test/fixtures/block-binding/program/actual.js
similarity index 100%
rename from test/fixtures/block-binding/ignore-root/actual.js
rename to test/fixtures/block-binding/program/actual.js
diff --git a/test/fixtures/block-binding/program/expected.js b/test/fixtures/block-binding/program/expected.js
new file mode 100644
index 0000000000..593f2c31b6
--- /dev/null
+++ b/test/fixtures/block-binding/program/expected.js
@@ -0,0 +1,7 @@
+(function () {
+  var arr = [
+    1,
+    2,
+    3
+  ];
+})();
diff --git a/test/fixtures/classes/accessing-super-without-having-one/actual.js b/test/fixtures/classes/accessing-super-without-having-one/actual.js
new file mode 100644
index 0000000000..023c8c5d75
--- /dev/null
+++ b/test/fixtures/classes/accessing-super-without-having-one/actual.js
@@ -0,0 +1,5 @@
+class Test {
+  constructor() {
+    super();
+  }
+}
diff --git a/test/fixtures/classes/accessing-super-without-having-one/options.json b/test/fixtures/classes/accessing-super-without-having-one/options.json
new file mode 100644
index 0000000000..bef99851e8
--- /dev/null
+++ b/test/fixtures/classes/accessing-super-without-having-one/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "cannot access super as this class has none"
+}
diff --git a/test/fixtures/classes/defining-constructor-as-a-mutator/actual.js b/test/fixtures/classes/defining-constructor-as-a-mutator/actual.js
new file mode 100644
index 0000000000..4de089b72a
--- /dev/null
+++ b/test/fixtures/classes/defining-constructor-as-a-mutator/actual.js
@@ -0,0 +1,4 @@
+class Test {
+  get constructor() {
+  }
+}
diff --git a/test/fixtures/classes/defining-constructor-as-a-mutator/options.json b/test/fixtures/classes/defining-constructor-as-a-mutator/options.json
new file mode 100644
index 0000000000..2761b2ba72
--- /dev/null
+++ b/test/fixtures/classes/defining-constructor-as-a-mutator/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "unknown kind for constructor method"
+}
diff --git a/test/fixtures/classes/no-accessing-super-properties/actual.js b/test/fixtures/classes/no-accessing-super-properties/actual.js
new file mode 100644
index 0000000000..51195a3c6f
--- /dev/null
+++ b/test/fixtures/classes/no-accessing-super-properties/actual.js
@@ -0,0 +1,5 @@
+class Test extends Foo {
+  constructor() {
+    super.test.whatever;
+  }
+}
diff --git a/test/fixtures/classes/no-accessing-super-properties/options.json b/test/fixtures/classes/no-accessing-super-properties/options.json
new file mode 100644
index 0000000000..62d82f26d2
--- /dev/null
+++ b/test/fixtures/classes/no-accessing-super-properties/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "cannot access super properties"
+}
diff --git a/test/fixtures/classes/no-calling-super-properties/actual.js b/test/fixtures/classes/no-calling-super-properties/actual.js
new file mode 100644
index 0000000000..7e8774ef63
--- /dev/null
+++ b/test/fixtures/classes/no-calling-super-properties/actual.js
@@ -0,0 +1,5 @@
+class Test extends Foo {
+  constructor() {
+    super.test.whatever();
+  }
+}
diff --git a/test/fixtures/classes/no-calling-super-properties/options.json b/test/fixtures/classes/no-calling-super-properties/options.json
new file mode 100644
index 0000000000..62d82f26d2
--- /dev/null
+++ b/test/fixtures/classes/no-calling-super-properties/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "cannot access super properties"
+}
diff --git a/test/fixtures/computed-property-names/method/actual.js b/test/fixtures/computed-property-names/method/actual.js
new file mode 100644
index 0000000000..c8997817dc
--- /dev/null
+++ b/test/fixtures/computed-property-names/method/actual.js
@@ -0,0 +1,5 @@
+var obj = {
+  [foobar]() {
+    return "foobar"
+  }
+};
diff --git a/test/fixtures/computed-property-names/method/expected.js b/test/fixtures/computed-property-names/method/expected.js
new file mode 100644
index 0000000000..a2d1eee068
--- /dev/null
+++ b/test/fixtures/computed-property-names/method/expected.js
@@ -0,0 +1,6 @@
+var obj = function (obj) {
+    obj[foobar] = function () {
+        return 'foobar';
+    };
+    return obj;
+}({});
diff --git a/test/fixtures/constants/block-statement/actual.js b/test/fixtures/constants/block-statement/actual.js
new file mode 100644
index 0000000000..e0b2b04ea0
--- /dev/null
+++ b/test/fixtures/constants/block-statement/actual.js
@@ -0,0 +1,4 @@
+for (let i in arr) {
+  const MULTIPLIER = 5;
+  console.log(arr[i] * MULTIPLIER);
+}
diff --git a/test/fixtures/constants/block-statement/expected.js b/test/fixtures/constants/block-statement/expected.js
new file mode 100644
index 0000000000..31d62981de
--- /dev/null
+++ b/test/fixtures/constants/block-statement/expected.js
@@ -0,0 +1,8 @@
+(function () {
+  for (var i in arr) {
+    (function () {
+      var MULTIPLIER = 5;
+      console.log(arr[i] * MULTIPLIER);
+    }());
+  }
+}());
diff --git a/test/fixtures/constants/no-assignment/actual.js b/test/fixtures/constants/no-assignment/actual.js
new file mode 100644
index 0000000000..296ce9b558
--- /dev/null
+++ b/test/fixtures/constants/no-assignment/actual.js
@@ -0,0 +1,3 @@
+const MULTIPLIER = 5;
+
+MULTIPLIER = "overwrite";
diff --git a/test/fixtures/constants/no-assignment/options.json b/test/fixtures/constants/no-assignment/options.json
new file mode 100644
index 0000000000..9b96d41ac9
--- /dev/null
+++ b/test/fixtures/constants/no-assignment/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "MULTIPLIER is read-only"
+}
diff --git a/test/fixtures/constants/no-declaration/actual.js b/test/fixtures/constants/no-declaration/actual.js
new file mode 100644
index 0000000000..ccb0ca0d05
--- /dev/null
+++ b/test/fixtures/constants/no-declaration/actual.js
@@ -0,0 +1,3 @@
+const MULTIPLIER = 5;
+
+var MULTIPLIER = "overwrite";
diff --git a/test/fixtures/constants/no-declaration/options.json b/test/fixtures/constants/no-declaration/options.json
new file mode 100644
index 0000000000..9b96d41ac9
--- /dev/null
+++ b/test/fixtures/constants/no-declaration/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "MULTIPLIER is read-only"
+}
diff --git a/test/fixtures/constants/program/actual.js b/test/fixtures/constants/program/actual.js
new file mode 100644
index 0000000000..2570895af8
--- /dev/null
+++ b/test/fixtures/constants/program/actual.js
@@ -0,0 +1,5 @@
+const MULTIPLIER = 5;
+
+for (var i in arr) {
+  console.log(arr[i] * MULTIPLIER);
+}
diff --git a/test/fixtures/constants/program/expected.js b/test/fixtures/constants/program/expected.js
new file mode 100644
index 0000000000..ab1e06254b
--- /dev/null
+++ b/test/fixtures/constants/program/expected.js
@@ -0,0 +1,6 @@
+(function () {
+  var MULTIPLIER = 5;
+  for (var i in arr) {
+      console.log(arr[i] * MULTIPLIER);
+  }
+}());
diff --git a/test/fixtures/errors/syntax/actual.js b/test/fixtures/errors/syntax/actual.js
new file mode 100644
index 0000000000..36651f967c
--- /dev/null
+++ b/test/fixtures/errors/syntax/actual.js
@@ -0,0 +1,3 @@
+arr.map(function () {
+  return $@!@#;
+});
diff --git a/test/fixtures/errors/syntax/options.json b/test/fixtures/errors/syntax/options.json
new file mode 100644
index 0000000000..3f3c5af1e7
--- /dev/null
+++ b/test/fixtures/errors/syntax/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Line 2: Unexpected token ILLEGAL"
+}
diff --git a/test/fixtures/spread/method-call-array-literal/actual.js b/test/fixtures/spread/method-call-array-literal/actual.js
new file mode 100644
index 0000000000..2d1a0bb716
--- /dev/null
+++ b/test/fixtures/spread/method-call-array-literal/actual.js
@@ -0,0 +1 @@
+f(...[1, 2, 3]);
diff --git a/test/fixtures/spread/method-call-array-literal/expected.js b/test/fixtures/spread/method-call-array-literal/expected.js
new file mode 100644
index 0000000000..987a197900
--- /dev/null
+++ b/test/fixtures/spread/method-call-array-literal/expected.js
@@ -0,0 +1 @@
+f.apply(null, [1, 2, 3]);
diff --git a/test/index.js b/test/index.js
index 9edc04584e..c0f17cb3b3 100644
--- a/test/index.js
+++ b/test/index.js
@@ -7,6 +7,14 @@ var humanise = function (val) {
   return val.replace(/-/g, " ");
 };
 
+var readFile = function (filename) {
+  if (fs.existsSync(filename)) {
+    return fs.readFileSync(filename);
+  } else {
+    return "";
+  }
+};
+
 var fixturesDir = __dirname + "/fixtures";
 
 _.each(fs.readdirSync(fixturesDir), function (suiteName) {
@@ -24,14 +32,26 @@ _.each(fs.readdirSync(fixturesDir), function (suiteName) {
       test(humanise(taskName), function () {
         var actualLoc = taskDir + "/actual.js";
 
-        var actual = fs.readFileSync(actualLoc, "utf8");
-        var expect = fs.readFileSync(taskDir + "/expected.js", "utf8");
+        var actual = readFile(actualLoc);
+        var expect = readFile(taskDir + "/expected.js");
 
         var taskOptsLoc = taskDir + "/options.json";
         var taskOpts = _.merge({ filename: actualLoc }, _.cloneDeep(suiteOpts));
         if (fs.existsSync(taskOptsLoc)) _.merge(taskOpts, require(taskOptsLoc));
 
-        transform.test(actual, expect, taskOpts);
+        var test = function () {
+          transform.test(actual, expect, taskOpts);
+        };
+
+        var throwMsg = taskOpts.throws;
+        if (throwMsg) {
+          // internal api doesn't have this option but it's best not to pollute
+          // the options object with useless options
+          delete taskOpts.throws;
+          assert.throws(test, new RegExp(throwMsg));
+        } else {
+          test();
+        }
       });
     });
   });