diff --git a/packages/core/core/test/Parcel.test.js b/packages/core/core/test/Parcel.test.js
index 36b2681a5e0..fec67bc03bf 100644
--- a/packages/core/core/test/Parcel.test.js
+++ b/packages/core/core/test/Parcel.test.js
@@ -86,13 +86,13 @@ describe('ParcelAPI', function () {
   afterEach(() => workerFarm.end());
 
   describe('parcel.unstable_transform()', () => {
-    it('should transforms simple file', async () => {
+    it('should transform simple file', async () => {
       let parcel = createParcel({workerFarm});
       let res = await parcel.unstable_transform({
         filePath: path.join(__dirname, 'fixtures/parcel/index.js'),
       });
       let code = await res[0].getCode();
-      assert(code.includes('exports.default = "test"'));
+      assert(code.includes(`exports.default = 'test'`));
     });
 
     it('should transform with standalone mode', async () => {
@@ -103,9 +103,9 @@ describe('ParcelAPI', function () {
       });
       let code = await res[0].getCode();
 
-      assert(code.includes('require("./index.js")'));
-      assert(code.includes('new URL("index.js", "file:" + __filename);'));
-      assert(code.includes('import("index.js")'));
+      assert(code.includes(`require("./index.js")`));
+      assert(code.includes(`new URL("index.js", "file:" + __filename);`));
+      assert(code.includes(`import('index.js')`));
     });
   });
 
diff --git a/packages/core/integration-tests/test/cache.js b/packages/core/integration-tests/test/cache.js
index d5246bccf46..610ad380477 100644
--- a/packages/core/integration-tests/test/cache.js
+++ b/packages/core/integration-tests/test/cache.js
@@ -5875,17 +5875,17 @@ describe('cache', function () {
         },
         async update(b) {
           let res = await run(b.bundleGraph);
-          assert(res.includes(`let a = "a"`));
+          assert(res.includes(`let a = 'a'`));
 
           await overlayFS.writeFile(
             path.join(inputDir, 'src/entries/a.js'),
-            `export let a = "b";`,
+            `export let a = 'b';`,
           );
         },
       });
 
       let res = await run(b.bundleGraph);
-      assert(res.includes(`let a = "b"`));
+      assert(res.includes(`let a = 'b'`));
     });
 
     it('should invalidate when switching to a different packager for an inline bundle', async function () {
diff --git a/packages/core/integration-tests/test/html.js b/packages/core/integration-tests/test/html.js
index 9121106a27a..aa9b044765b 100644
--- a/packages/core/integration-tests/test/html.js
+++ b/packages/core/integration-tests/test/html.js
@@ -2689,7 +2689,7 @@ describe('html', function () {
     await getNextBuild(b);
 
     let html = await outputFS.readFile('/dist/index.html', 'utf8');
-    assert(html.includes(`console.log("test")`));
+    assert(html.includes(`console.log('test')`));
 
     await overlayFS.writeFile(
       path.join(__dirname, '/html-inline-js-require/test.js'),
@@ -2698,7 +2698,7 @@ describe('html', function () {
     await getNextBuild(b);
 
     html = await outputFS.readFile(path.join(distDir, '/index.html'), 'utf8');
-    assert(html.includes(`console.log("foo")`));
+    assert(html.includes(`console.log('foo')`));
   });
 
   it('should invalidate parent bundle when nested inline bundles change', async function () {
diff --git a/packages/core/integration-tests/test/incremental-bundling.js b/packages/core/integration-tests/test/incremental-bundling.js
index 4eacb8f4c36..0e767145fe3 100644
--- a/packages/core/integration-tests/test/incremental-bundling.js
+++ b/packages/core/integration-tests/test/incremental-bundling.js
@@ -90,7 +90,7 @@ console.log('adding a new console');`,
             result.bundleGraph.getBundles()[0].filePath,
             'utf8',
           );
-          assert(contents.includes(`console.log("adding a new console")`));
+          assert(contents.includes(`console.log('adding a new console')`));
         } finally {
           if (subscription) {
             await subscription.unsubscribe();
@@ -132,7 +132,7 @@ console.log('adding a new console');`,
             result.bundleGraph.getBundles()[0].filePath,
             'utf8',
           );
-          assert(contents.includes(`console.log("adding a new console")`));
+          assert(contents.includes(`console.log('adding a new console')`));
         } finally {
           if (subscription) {
             await subscription.unsubscribe();
@@ -174,7 +174,7 @@ console.log('adding a new console');`,
             result.bundleGraph.getBundles()[0].filePath,
             'utf8',
           );
-          assert(contents.includes(`console.log("adding a new console")`));
+          assert(contents.includes(`console.log('adding a new console')`));
         } finally {
           if (subscription) {
             await subscription.unsubscribe();
@@ -217,7 +217,7 @@ console.log(a);
             'utf8',
           );
           assert(
-            contents.includes(`console.log("index.js - updated string");`),
+            contents.includes(`console.log('index.js - updated string');`),
           );
         } finally {
           if (subscription) {
@@ -308,7 +308,7 @@ module.exports = a;`,
             'utf8',
           );
 
-          assert(contents.includes(`console.log("adding a new console")`));
+          assert(contents.includes(`console.log('adding a new console')`));
 
           let bundleOutput = await run(result.bundleGraph);
           assert.equal(bundleOutput, 'a updated');
@@ -404,7 +404,7 @@ console.log(a, 'updated');`,
           'utf8',
         );
 
-        assert(contents.includes(`console.log((0, _a.a), "updated");`));
+        assert(contents.includes(`console.log((0, _a.a), 'updated');`));
 
         let bundleCSS = result.bundleGraph.getBundles()[1];
         assert.equal(bundleCSS.type, 'css');
@@ -504,7 +504,7 @@ console.log(a);
           'utf8',
         );
 
-        assert(contents.includes(`console.log("index.js", (0, _b.b));`));
+        assert(contents.includes(`console.log('index.js', (0, _b.b));`));
       } finally {
         if (subscription) {
           await subscription.unsubscribe();
@@ -612,7 +612,7 @@ console.log(a, b);
         );
         assert(
           dynamicContent.includes(`parcelHelpers.export(exports, "b", ()=>b);
-const b = "b";`),
+const b = 'b';`),
         );
       } finally {
         if (subscription) {
diff --git a/packages/core/integration-tests/test/javascript.js b/packages/core/integration-tests/test/javascript.js
index e1d9c7839f8..4f941fb5645 100644
--- a/packages/core/integration-tests/test/javascript.js
+++ b/packages/core/integration-tests/test/javascript.js
@@ -1109,8 +1109,8 @@ describe('javascript', function () {
     let main = await outputFS.readFile(b.getBundles()[0].filePath, 'utf8');
     dedicated = await outputFS.readFile(dedicated.filePath, 'utf8');
     shared = await outputFS.readFile(shared.filePath, 'utf8');
-    assert(/new Worker(.*?, {[\n\s]+type: "module"[\n\s]+})/.test(main));
-    assert(/new SharedWorker(.*?, {[\n\s]+type: "module"[\n\s]+})/.test(main));
+    assert(/new Worker(.*?, {[\n\s]+type: 'module'[\n\s]+})/.test(main));
+    assert(/new SharedWorker(.*?, {[\n\s]+type: 'module'[\n\s]+})/.test(main));
   });
 
   for (let shouldScopeHoist of [true, false]) {
@@ -1263,8 +1263,8 @@ describe('javascript', function () {
     );
 
     let main = await outputFS.readFile(b.getBundles()[0].filePath, 'utf8');
-    assert(/new Worker(.*?, {[\n\s]+name: "worker"[\n\s]+})/.test(main));
-    assert(/new SharedWorker(.*?, {[\n\s]+name: "shared"[\n\s]+})/.test(main));
+    assert(/new Worker(.*?, {[\n\s]+name: 'worker'[\n\s]+})/.test(main));
+    assert(/new SharedWorker(.*?, {[\n\s]+name: 'shared'[\n\s]+})/.test(main));
   });
 
   it('should error if importing in a worker without type: module', async function () {
@@ -1463,7 +1463,7 @@ describe('javascript', function () {
     ]);
 
     let res = await outputFS.readFile(b.getBundles()[0].filePath, 'utf8');
-    assert(res.includes(`importScripts("imported.js")`));
+    assert(res.includes(`importScripts('imported.js')`));
   });
 
   it('should ignore importScripts in script workers when not passed a string literal', async function () {
@@ -1509,7 +1509,7 @@ describe('javascript', function () {
     ]);
 
     let res = await outputFS.readFile(b.getBundles()[1].filePath, 'utf8');
-    assert(res.includes(`importScripts("https://unpkg.com/parcel")`));
+    assert(res.includes(`importScripts('https://unpkg.com/parcel')`));
   });
 
   it('should support bundling service-workers', async function () {
@@ -1584,7 +1584,7 @@ describe('javascript', function () {
     let main = bundles.find(b => !b.env.isWorker());
     let mainContents = await outputFS.readFile(main.filePath, 'utf8');
     assert(
-      /navigator.serviceWorker.register\(.*?, {[\n\s]*scope: "foo"[\n\s]*}\)/.test(
+      /navigator.serviceWorker.register\(.*?, {[\n\s]*scope: 'foo'[\n\s]*}\)/.test(
         mainContents,
       ),
     );
@@ -4386,7 +4386,7 @@ describe('javascript', function () {
     let res = await run(b);
     assert.equal(
       res.default,
-      `<p>test</p>\n<script>console.log("hi");\n\n</script>\n`,
+      `<p>test</p>\n<script>console.log('hi');\n\n</script>\n`,
     );
   });
 
diff --git a/packages/core/integration-tests/test/output-formats.js b/packages/core/integration-tests/test/output-formats.js
index 22832c2138b..b86e43255e9 100644
--- a/packages/core/integration-tests/test/output-formats.js
+++ b/packages/core/integration-tests/test/output-formats.js
@@ -1060,7 +1060,7 @@ describe('output formats', function () {
         .find(bundle => bundle.name.startsWith('async'));
       assert(
         new RegExp(
-          `getBundleURL\\("[a-zA-Z0-9]+"\\) \\+ "` +
+          `getBundleURL\\('[a-zA-Z0-9]+'\\) \\+ "` +
             path.basename(asyncBundle.filePath) +
             '"',
         ).test(entry),
diff --git a/packages/core/integration-tests/test/sourcemaps.js b/packages/core/integration-tests/test/sourcemaps.js
index 39040fd4a4e..8e9d1ecf171 100644
--- a/packages/core/integration-tests/test/sourcemaps.js
+++ b/packages/core/integration-tests/test/sourcemaps.js
@@ -1258,7 +1258,7 @@ describe('sourcemaps', function () {
       source: input,
       generated: raw,
       str: "console.log('foo')",
-      generatedStr: `console.log("foo")`,
+      generatedStr: `console.log('foo')`,
       sourcePath,
     });
 
@@ -1267,7 +1267,7 @@ describe('sourcemaps', function () {
       source: input,
       generated: raw,
       str: "console.log('bar')",
-      generatedStr: `console.log("bar")`,
+      generatedStr: `console.log('bar')`,
       sourcePath,
     });
 
@@ -1276,7 +1276,7 @@ describe('sourcemaps', function () {
       source: input,
       generated: raw,
       str: "console.log('baz')",
-      generatedStr: `console.log("baz")`,
+      generatedStr: `console.log('baz')`,
       sourcePath,
     });
 
@@ -1285,7 +1285,7 @@ describe('sourcemaps', function () {
       source: input,
       generated: raw,
       str: "console.log('idhf')",
-      generatedStr: `console.log("idhf")`,
+      generatedStr: `console.log('idhf')`,
       sourcePath,
     });
   });
@@ -1425,7 +1425,7 @@ describe('sourcemaps', function () {
       source: sourceContent,
       generated: raw,
       str: `foo = 'Lorem ipsum`,
-      generatedStr: `foo = "Lorem ipsum`,
+      generatedStr: `foo = 'Lorem ipsum`,
       sourcePath,
     });
   });
diff --git a/packages/core/integration-tests/test/svg.js b/packages/core/integration-tests/test/svg.js
index f8e2d06ad5f..6eebd2c937f 100644
--- a/packages/core/integration-tests/test/svg.js
+++ b/packages/core/integration-tests/test/svg.js
@@ -195,7 +195,7 @@ describe('svg', function () {
       ),
     );
     assert(svg.includes('<script>'));
-    assert(svg.includes(`console.log("script")`));
+    assert(svg.includes(`console.log('script')`));
     assert(!svg.includes('import '));
   });