diff --git a/package-lock.json b/package-lock.json
index a42da4db..e340aa5c 100644
--- a/package-lock.json
+++ b/package-lock.json
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+              "version": "1.0.0",
+              "resolved": "https://registry.npmjs.org/define-property/-/define-property-1.0.0.tgz",
+              "integrity": "sha1-dp66rz9KY6rTr56NMEybvnm/sOY=",
+              "dev": true,
+              "requires": {
+                "is-descriptor": "1.0.2"
+              }
+            },
+            "extend-shallow": {
+              "version": "2.0.1",
+              "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-2.0.1.tgz",
+              "integrity": "sha1-Ua99YUrZqfYQ6huvu5idaxxWiQ8=",
+              "dev": true,
+              "requires": {
+                "is-extendable": "0.1.1"
+              }
+            }
+          }
+        },
+        "chokidar": {
+          "version": "2.0.2",
+          "resolved": "https://registry.npmjs.org/chokidar/-/chokidar-2.0.2.tgz",
+          "integrity": "sha512-l32Hw3wqB0L2kGVmSbK/a+xXLDrUEsc84pSgMkmwygHvD7ubRsP/vxxHa5BtB6oix1XLLVCHyYMsckRXxThmZw==",
+          "dev": true,
+          "requires": {
+            "anymatch": "2.0.0",
+            "async-each": "1.0.1",
+            "braces": "2.3.1",
+            "fsevents": "1.1.3",
+            "glob-parent": "3.1.0",
+            "inherits": "2.0.3",
+            "is-binary-path": "1.0.1",
+            "is-glob": "4.0.0",
+            "normalize-path": "2.1.1",
+            "path-is-absolute": "1.0.1",
+            "readdirp": "2.1.0",
+            "upath": "1.0.4"
+          }
+        },
+        "expand-brackets": {
+          "version": "2.1.4",
+          "resolved": "https://registry.npmjs.org/expand-brackets/-/expand-brackets-2.1.4.tgz",
+          "integrity": "sha1-t3c14xXOMPa27/D4OwQVGiJEliI=",
+          "dev": true,
+          "requires": {
+            "debug": "2.6.9",
+            "define-property": "0.2.5",
+            "extend-shallow": "2.0.1",
+            "posix-character-classes": "0.1.1",
+            "regex-not": "1.0.2",
+            "snapdragon": "0.8.2",
+            "to-regex": "3.0.2"
+          },
+          "dependencies": {
+            "define-property": {
+              "version": "0.2.5",
+              "resolved": "https://registry.npmjs.org/define-property/-/define-property-0.2.5.tgz",
+              "integrity": "sha1-w1se+RjsPJkPmlvFe+BKrOxcgRY=",
+              "dev": true,
+              "requires": {
+                "is-descriptor": "0.1.6"
+              }
+            },
+            "extend-shallow": {
+              "version": "2.0.1",
+              "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-2.0.1.tgz",
+              "integrity": "sha1-Ua99YUrZqfYQ6huvu5idaxxWiQ8=",
+              "dev": true,
+              "requires": {
+                "is-extendable": "0.1.1"
+              }
+            },
+            "is-descriptor": {
+              "version": "0.1.6",
+              "resolved": "https://registry.npmjs.org/is-descriptor/-/is-descriptor-0.1.6.tgz",
+              "integrity": "sha512-avDYr0SB3DwO9zsMov0gKCESFYqCnE4hq/4z3TdUlukEy5t9C0YRq7HLrsN52NAcqXKaepeCD0n+B0arnVG3Hg==",
+              "dev": true,
+              "requires": {
+                "is-accessor-descriptor": "0.1.6",
+                "is-data-descriptor": "0.1.4",
+                "kind-of": "5.1.0"
+              }
+            },
+            "kind-of": {
+              "version": "5.1.0",
+              "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-5.1.0.tgz",
+              "integrity": "sha512-NGEErnH6F2vUuXDh+OlbcKW7/wOcfdRHaZ7VWtqCztfHri/++YKmP51OdWeGPuqCOba6kk2OTe5d02VmTB80Pw==",
+              "dev": true
+            }
+          }
+        },
+        "extglob": {
+          "version": "2.0.4",
+          "resolved": "https://registry.npmjs.org/extglob/-/extglob-2.0.4.tgz",
+          "integrity": "sha512-Nmb6QXkELsuBr24CJSkilo6UHHgbekK5UiZgfE6UHD3Eb27YC6oD+bhcT+tJ6cl8dmsgdQxnWlcry8ksBIBLpw==",
+          "dev": true,
+          "requires": {
+            "array-unique": "0.3.2",
+            "define-property": "1.0.0",
+            "expand-brackets": "2.1.4",
+            "extend-shallow": "2.0.1",
+            "fragment-cache": "0.2.1",
+            "regex-not": "1.0.2",
+            "snapdragon": "0.8.2",
+            "to-regex": "3.0.2"
+          },
+          "dependencies": {
+            "define-property": {
+              "version": "1.0.0",
+              "resolved": "https://registry.npmjs.org/define-property/-/define-property-1.0.0.tgz",
+              "integrity": "sha1-dp66rz9KY6rTr56NMEybvnm/sOY=",
+              "dev": true,
+              "requires": {
+                "is-descriptor": "1.0.2"
+              }
+            },
+            "extend-shallow": {
+              "version": "2.0.1",
+              "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-2.0.1.tgz",
+              "integrity": "sha1-Ua99YUrZqfYQ6huvu5idaxxWiQ8=",
+              "dev": true,
+              "requires": {
+                "is-extendable": "0.1.1"
+              }
+            }
+          }
+        },
+        "fill-range": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-4.0.0.tgz",
+          "integrity": "sha1-1USBHUKPmOsGpj3EAtJAPDKMOPc=",
+          "dev": true,
+          "requires": {
+            "extend-shallow": "2.0.1",
+            "is-number": "3.0.0",
+            "repeat-string": "1.6.1",
+            "to-regex-range": "2.1.1"
+          },
+          "dependencies": {
+            "extend-shallow": {
+              "version": "2.0.1",
+              "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-2.0.1.tgz",
+              "integrity": "sha1-Ua99YUrZqfYQ6huvu5idaxxWiQ8=",
+              "dev": true,
+              "requires": {
+                "is-extendable": "0.1.1"
+              }
+            }
+          }
+        },
+        "glob-parent": {
+          "version": "3.1.0",
+          "resolved": "https://registry.npmjs.org/glob-parent/-/glob-parent-3.1.0.tgz",
+          "integrity": "sha1-nmr2KZ2NO9K9QEMIMr0RPfkGxa4=",
+          "dev": true,
+          "requires": {
+            "is-glob": "3.1.0",
+            "path-dirname": "1.0.2"
+          },
+          "dependencies": {
+            "is-glob": {
+              "version": "3.1.0",
+              "resolved": "https://registry.npmjs.org/is-glob/-/is-glob-3.1.0.tgz",
+              "integrity": "sha1-e6WuJCF4BKxwcHuWkiVnSGzD6Eo=",
+              "dev": true,
+              "requires": {
+                "is-extglob": "2.1.1"
+              }
+            }
+          }
+        },
+        "is-accessor-descriptor": {
+          "version": "0.1.6",
+          "resolved": "https://registry.npmjs.org/is-accessor-descriptor/-/is-accessor-descriptor-0.1.6.tgz",
+          "integrity": "sha1-qeEss66Nh2cn7u84Q/igiXtcmNY=",
+          "dev": true,
+          "requires": {
+            "kind-of": "3.2.2"
+          },
+          "dependencies": {
+            "kind-of": {
+              "version": "3.2.2",
+              "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-3.2.2.tgz",
+              "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
+              "dev": true,
+              "requires": {
+                "is-buffer": "1.1.6"
+              }
+            }
+          }
+        },
+        "is-data-descriptor": {
+          "version": "0.1.4",
+          "resolved": "https://registry.npmjs.org/is-data-descriptor/-/is-data-descriptor-0.1.4.tgz",
+          "integrity": "sha1-C17mSDiOLIYCgueT8YVv7D8wG1Y=",
+          "dev": true,
+          "requires": {
+            "kind-of": "3.2.2"
+          },
+          "dependencies": {
+            "kind-of": {
+              "version": "3.2.2",
+              "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-3.2.2.tgz",
+              "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
+              "dev": true,
+              "requires": {
+                "is-buffer": "1.1.6"
+              }
+            }
+          }
+        },
+        "is-extglob": {
+          "version": "2.1.1",
+          "resolved": "https://registry.npmjs.org/is-extglob/-/is-extglob-2.1.1.tgz",
+          "integrity": "sha1-qIwCU1eR8C7TfHahueqXc8gz+MI=",
+          "dev": true
+        },
+        "is-glob": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/is-glob/-/is-glob-4.0.0.tgz",
+          "integrity": "sha1-lSHHaEXMJhCoUgPd8ICpWML/q8A=",
+          "dev": true,
+          "requires": {
+            "is-extglob": "2.1.1"
+          }
+        },
+        "is-number": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/is-number/-/is-number-3.0.0.tgz",
+          "integrity": "sha1-JP1iAaR4LPUFYcgQJ2r8fRLXEZU=",
+          "dev": true,
+          "requires": {
+            "kind-of": "3.2.2"
+          },
+          "dependencies": {
+            "kind-of": {
+              "version": "3.2.2",
+              "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-3.2.2.tgz",
+              "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
+              "dev": true,
+              "requires": {
+                "is-buffer": "1.1.6"
+              }
+            }
+          }
+        },
+        "isobject": {
+          "version": "3.0.1",
+          "resolved": "https://registry.npmjs.org/isobject/-/isobject-3.0.1.tgz",
+          "integrity": "sha1-TkMekrEalzFjaqH5yNHMvP2reN8=",
+          "dev": true
+        },
+        "kind-of": {
+          "version": "6.0.2",
+          "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-6.0.2.tgz",
+          "integrity": "sha512-s5kLOcnH0XqDO+FvuaLX8DDjZ18CGFk7VygH40QoKPUQhW4e2rvM0rwUq0t8IQDOwYSeLK01U90OjzBTme2QqA==",
+          "dev": true
+        },
+        "micromatch": {
+          "version": "3.1.9",
+          "resolved": "https://registry.npmjs.org/micromatch/-/micromatch-3.1.9.tgz",
+          "integrity": "sha512-SlIz6sv5UPaAVVFRKodKjCg48EbNoIhgetzfK/Cy0v5U52Z6zB136M8tp0UC9jM53LYbmIRihJszvvqpKkfm9g==",
+          "dev": true,
+          "requires": {
+            "arr-diff": "4.0.0",
+            "array-unique": "0.3.2",
+            "braces": "2.3.1",
+            "define-property": "2.0.2",
+            "extend-shallow": "3.0.2",
+            "extglob": "2.0.4",
+            "fragment-cache": "0.2.1",
+            "kind-of": "6.0.2",
+            "nanomatch": "1.2.9",
+            "object.pick": "1.3.0",
+            "regex-not": "1.0.2",
+            "snapdragon": "0.8.2",
+            "to-regex": "3.0.2"
+          }
+        }
       }
     },
     "webidl-conversions": {
@@ -11752,14 +11993,14 @@
       "dev": true
     },
     "webpack": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/webpack/-/webpack-4.0.1.tgz",
-      "integrity": "sha512-jHQNMmKPElreOYLCxR7SHfPnbhcqRT9O7lYPOMDR6Gt5XueJ7tH7JReXm4uMFstBKf7rj2Y7AD3LiMKR2zexYA==",
+      "version": "4.1.1",
+      "resolved": "https://registry.npmjs.org/webpack/-/webpack-4.1.1.tgz",
+      "integrity": "sha512-PwxKH81yLjbPyBSZvPj/Ji9pT99XOGFA0t6zipoOKOMNRZ+09N39J5Uzcx3rYKnsHgKwDnfGkvzac4MF2Taknw==",
       "dev": true,
       "requires": {
         "acorn": "5.2.1",
         "acorn-dynamic-import": "3.0.0",
-        "ajv": "6.2.0",
+        "ajv": "6.2.1",
         "ajv-keywords": "3.1.0",
         "chrome-trace-event": "0.1.2",
         "enhanced-resolve": "4.0.0",
@@ -11773,15 +12014,15 @@
         "node-libs-browser": "2.1.0",
         "schema-utils": "0.4.5",
         "tapable": "1.0.0",
-        "uglifyjs-webpack-plugin": "1.2.2",
-        "watchpack": "1.4.0",
+        "uglifyjs-webpack-plugin": "1.2.3",
+        "watchpack": "1.5.0",
         "webpack-sources": "1.1.0"
       },
       "dependencies": {
         "ajv": {
-          "version": "6.2.0",
-          "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.2.0.tgz",
-          "integrity": "sha1-r6wpW7qgFSRJ5SJ0LkVHwa6TKNI=",
+          "version": "6.2.1",
+          "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.2.1.tgz",
+          "integrity": "sha1-KKarxJOiq+D7TIUHrK7bQ/pVBnE=",
           "dev": true,
           "requires": {
             "fast-deep-equal": "1.0.0",
@@ -11821,7 +12062,7 @@
             "isobject": "3.0.1",
             "kind-of": "6.0.2",
             "repeat-element": "1.1.2",
-            "snapdragon": "0.8.1",
+            "snapdragon": "0.8.2",
             "snapdragon-node": "2.1.1",
             "split-string": "3.1.0",
             "to-regex": "3.0.2"
@@ -11858,7 +12099,7 @@
             "extend-shallow": "2.0.1",
             "posix-character-classes": "0.1.1",
             "regex-not": "1.0.2",
-            "snapdragon": "0.8.1",
+            "snapdragon": "0.8.2",
             "to-regex": "3.0.2"
           },
           "dependencies": {
@@ -11911,7 +12152,7 @@
             "extend-shallow": "2.0.1",
             "fragment-cache": "0.2.1",
             "regex-not": "1.0.2",
-            "snapdragon": "0.8.1",
+            "snapdragon": "0.8.2",
             "to-regex": "3.0.2"
           },
           "dependencies": {
@@ -12047,7 +12288,7 @@
             "nanomatch": "1.2.9",
             "object.pick": "1.3.0",
             "regex-not": "1.0.2",
-            "snapdragon": "0.8.1",
+            "snapdragon": "0.8.2",
             "to-regex": "3.0.2"
           }
         }
@@ -12156,13 +12397,12 @@
       "dev": true
     },
     "worker-farm": {
-      "version": "1.5.4",
-      "resolved": "https://registry.npmjs.org/worker-farm/-/worker-farm-1.5.4.tgz",
-      "integrity": "sha512-ITyClEvcfv0ozqJl1vmWFWhvI+OIrkbInYqkEPE50wFPXj8J9Gd3FYf8+CkZJXJJsQBYe+2DvmoK9Zhx5w8W+w==",
+      "version": "1.6.0",
+      "resolved": "https://registry.npmjs.org/worker-farm/-/worker-farm-1.6.0.tgz",
+      "integrity": "sha512-6w+3tHbM87WnSWnENBUvA2pxJPLhQUg5LKwUQHq3r+XPhIM+Gh2R5ycbwPCyuGbNg+lPgdcnQUhuC02kJCvffQ==",
       "dev": true,
       "requires": {
-        "errno": "0.1.7",
-        "xtend": "4.0.1"
+        "errno": "0.1.7"
       },
       "dependencies": {
         "errno": {
@@ -12211,8 +12451,7 @@
     "wrappy": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
-      "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=",
-      "dev": true
+      "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8="
     },
     "wreck": {
       "version": "12.5.1",
diff --git a/package.json b/package.json
index 07a827d0..ba5d5a67 100644
--- a/package.json
+++ b/package.json
@@ -33,6 +33,7 @@
   },
   "dependencies": {
     "async": "^2.4.1",
+    "glob": "^7.1.2",
     "loader-utils": "^1.1.0",
     "schema-utils": "^0.4.5",
     "webpack-sources": "^1.1.0"
@@ -65,7 +66,7 @@
     "raw-loader": "^0.5.1",
     "standard-version": "^4.3.0",
     "style-loader": "^0.19.1",
-    "webpack": "^4.0.0",
+    "webpack": "^4.1.1",
     "webpack-defaults": "^2.0.0-rc.4"
   },
   "engines": {
diff --git a/src/index.js b/src/index.js
index 2dc41cb8..706e19d2 100644
--- a/src/index.js
+++ b/src/index.js
@@ -351,6 +351,10 @@ class ExtractTextPlugin {
               extractedChunk
             );
 
+            if (!source.size()) {
+              return;
+            }
+
             const getPath = (format) =>
               compilation
                 .getPath(format, {
diff --git a/test/__snapshots__/webpack-integration.test.js.snap b/test/__snapshots__/webpack-integration.test.js.snap
index ee303141..73dc540b 100644
--- a/test/__snapshots__/webpack-integration.test.js.snap
+++ b/test/__snapshots__/webpack-integration.test.js.snap
@@ -42,6 +42,11 @@ c
 "
 `;
 
+exports[`Webpack Integration Tests empty-chunk 1`] = `
+"a
+"
+`;
+
 exports[`Webpack Integration Tests merging-chunk 1`] = `
 "a
 b
@@ -95,8 +100,6 @@ c
 "
 `;
 
-exports[`Webpack Integration Tests multiple-entries-filename 3`] = `""`;
-
 exports[`Webpack Integration Tests nested 1`] = `
 "a
 b
diff --git a/test/cases/empty-chunk/a.js b/test/cases/empty-chunk/a.js
new file mode 100644
index 00000000..2e3802cb
--- /dev/null
+++ b/test/cases/empty-chunk/a.js
@@ -0,0 +1,2 @@
+require('./a.txt');
+require('./b.txt');
diff --git a/test/cases/empty-chunk/a.txt b/test/cases/empty-chunk/a.txt
new file mode 100644
index 00000000..78981922
--- /dev/null
+++ b/test/cases/empty-chunk/a.txt
@@ -0,0 +1 @@
+a
diff --git a/test/cases/empty-chunk/b.js b/test/cases/empty-chunk/b.js
new file mode 100644
index 00000000..4d81e904
--- /dev/null
+++ b/test/cases/empty-chunk/b.js
@@ -0,0 +1,2 @@
+require('./b.txt');
+require('./c.txt');
diff --git a/test/cases/empty-chunk/b.txt b/test/cases/empty-chunk/b.txt
new file mode 100644
index 00000000..61780798
--- /dev/null
+++ b/test/cases/empty-chunk/b.txt
@@ -0,0 +1 @@
+b
diff --git a/test/cases/empty-chunk/c.txt b/test/cases/empty-chunk/c.txt
new file mode 100644
index 00000000..f2ad6c76
--- /dev/null
+++ b/test/cases/empty-chunk/c.txt
@@ -0,0 +1 @@
+c
diff --git a/test/cases/empty-chunk/expected/main.css b/test/cases/empty-chunk/expected/main.css
new file mode 100644
index 00000000..78981922
--- /dev/null
+++ b/test/cases/empty-chunk/expected/main.css
@@ -0,0 +1 @@
+a
diff --git a/test/cases/empty-chunk/index.js b/test/cases/empty-chunk/index.js
new file mode 100644
index 00000000..6b5cc452
--- /dev/null
+++ b/test/cases/empty-chunk/index.js
@@ -0,0 +1,16 @@
+require('./a.txt');
+
+require.ensure(
+  [],
+  () => {
+    require('./a.js');
+  },
+  'async-chunk-a',
+);
+require.ensure(
+  [],
+  () => {
+    require('./b.js');
+  },
+  'async-chunk-b',
+);
diff --git a/test/cases/empty-chunk/webpack.config.js b/test/cases/empty-chunk/webpack.config.js
new file mode 100644
index 00000000..4fec4d09
--- /dev/null
+++ b/test/cases/empty-chunk/webpack.config.js
@@ -0,0 +1,22 @@
+import ExtractTextPlugin from '../../../src/index';
+
+module.exports = {
+  entry: './index',
+  optimization: {
+    splitChunks: {
+      cacheGroups: {
+        common: {
+          name: 'common',
+          chunks: 'async',
+          test: /async-chunk-(a|b)/,
+        },
+      },
+    },
+    runtimeChunk: true
+  },
+  plugins: [
+    new ExtractTextPlugin({
+      filename: '[name].css'
+    }),
+  ],
+};
diff --git a/test/webpack-integration.test.js b/test/webpack-integration.test.js
index 36fb4cb9..24f00295 100644
--- a/test/webpack-integration.test.js
+++ b/test/webpack-integration.test.js
@@ -6,6 +6,7 @@
 import fs from 'fs';
 import path from 'path';
 import webpack from 'webpack';
+import glob from 'glob';
 import ExtractTextPlugin from '../src';
 
 const cases = process.env.CASES
@@ -47,24 +48,20 @@ describe('Webpack Integration Tests', () => {
           require(testFile)(suite);
         }
         const expectedDirectory = path.join(testDirectory, 'expected');
-        fs.readdirSync(expectedDirectory).forEach((file) => {
-          const filePath = path.join(expectedDirectory, file);
-          const actualPath = path.join(outputDirectory, file);
-          expect(readFileOrEmpty(actualPath)).toEqual(
-            readFileOrEmpty(filePath)
-          );
-          expect(readFileOrEmpty(actualPath)).toMatchSnapshot();
-        });
+
+        glob
+          .sync('**/*.@(txt|css)', { cwd: outputDirectory })
+          .forEach((file) => {
+            const filePath = path.join(expectedDirectory, file);
+            const actualPath = path.join(outputDirectory, file);
+            expect(fs.existsSync(filePath)).toBeTruthy();
+            expect(fs.readFileSync(actualPath, 'utf-8')).toEqual(
+              fs.readFileSync(filePath, 'utf-8')
+            );
+            expect(fs.readFileSync(actualPath, 'utf-8')).toMatchSnapshot();
+          });
         done();
       });
     });
   });
 });
-
-function readFileOrEmpty(filePath) {
-  try {
-    return fs.readFileSync(filePath, 'utf-8');
-  } catch (e) {
-    return '';
-  }
-}