diff --git a/packages/babel-plugin-proposal-optional-catch-binding/test/fixtures/optional-catch-bindings/exec.js b/packages/babel-plugin-proposal-optional-catch-binding/test/fixtures/optional-catch-bindings/exec.js
index c55bbe53ac..ed44a1b315 100644
--- a/packages/babel-plugin-proposal-optional-catch-binding/test/fixtures/optional-catch-bindings/exec.js
+++ b/packages/babel-plugin-proposal-optional-catch-binding/test/fixtures/optional-catch-bindings/exec.js
@@ -6,7 +6,7 @@ const test = () => {
     return true;
   }
 }
-assert(test());
+expect(test()).toBe(true);
 
 const test2 = () => {
   try {
@@ -16,4 +16,4 @@ const test2 = () => {
     return true;
   }
 }
-assert(test2());
+expect(test2()).toBe(true);
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/duplicate-function-scope.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/duplicate-function-scope.js
index 3fd573afb4..f4f4d792f1 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/duplicate-function-scope.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/duplicate-function-scope.js
@@ -7,4 +7,4 @@ function test () {
   }();
 }
 
-assert(test(), "inner");
+expect(test()).toBe("inner");
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/for-continuation-outer-reference.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/for-continuation-outer-reference.js
index 16a171d571..f4485243fe 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/for-continuation-outer-reference.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/for-continuation-outer-reference.js
@@ -10,4 +10,4 @@ for (let index = 0; index < data.length; index++) {
     let fn = function () {item;};
 }
 
-assert(data.every(item => item));
+expect(data.every(item => item)).toBe(true);
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/scope-bindings.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/scope-bindings.js
index 9d9e2f634b..877467f94c 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/scope-bindings.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/scope-bindings.js
@@ -13,12 +13,12 @@ var res = transform(code, {
           Scope: {
             exit: function(path) {
               if (innerScope) {
-                assert(Object.keys(path.scope.bindings).length === 0, 'Inner scope should not have any bindings');
+                expect(Object.keys(path.scope.bindings)).toHaveLength(0);
                 innerScope = false;
                 return;
               }
 
-              assert(Object.keys(path.scope.bindings).length === 2, 'Outer scope subsume the inner-scope binding');
+              expect(Object.keys(path.scope.bindings)).toHaveLength(2);
             }
           }
         }
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/switch-break.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/switch-break.js
index baeaa30410..ac8eff3b95 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/switch-break.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/exec/switch-break.js
@@ -2,7 +2,7 @@ if (true) {
   const x = 1;
   switch (x) {
     case 1: {
-      assert(x, 1);
+      expect(x).toBe(1);
       break;
     }
   }