From 480378649db2b87b4c627ddc6ef772d0307115e5 Mon Sep 17 00:00:00 2001
From: Shane Osbourne <shane.osbourne8@gmail.com>
Date: Sun, 29 Apr 2018 20:54:55 +0100
Subject: [PATCH] feat: (client-js) allow functions in client:js hook

---
 lib/client.js        | 35 ++++++++++++++++++++---------------
 lib/connect-utils.js |  1 +
 lib/hooks.js         |  6 +++---
 lib/snippet.js       | 14 ++++++++------
 4 files changed, 32 insertions(+), 24 deletions(-)

diff --git a/lib/client.js b/lib/client.js
index 8efbd34c9..b8ca19274 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -48,6 +48,20 @@ function notModified(res) {
     res.end();
 }
 
+function processItems(items) {
+    return [].concat(items)
+        .filter(Boolean)
+        .reduce((stringOutput, item) => {
+            if (typeof item === 'string') {
+                return stringOutput + item;
+            }
+            if (typeof item === 'function') {
+                return stringOutput + item();
+            }
+            return stringOutput;
+        }, "");
+}
+
 /**
  * Public method for returning either a middleware fn
  * or the content as a string
@@ -57,13 +71,11 @@ function notModified(res) {
  * @returns {*}
  */
 function init(options, requestBody, type) {
-    var gzipCached;
-
     /**
      * If the user asked for a file, simply return the string.
      */
     if (type && type === "file") {
-        return requestBody;
+        return processItems(requestBody);
     }
 
     /**
@@ -74,13 +86,12 @@ function init(options, requestBody, type) {
          * default to using the uncompressed string
          * @type {String}
          */
-        var output = requestBody;
+        var output = processItems(requestBody);
 
         /**
          * Set the appropriate headers for caching
          */
         setHeaders(res, output);
-
         if (isConditionalGet(req) && fresh(req.headers, res._headers)) {
             return notModified(res);
         }
@@ -91,16 +102,10 @@ function init(options, requestBody, type) {
          */
         if (supportsGzip(req)) {
             res.setHeader("Content-Encoding", "gzip");
-
-            if (!gzipCached) {
-                var buf = new Buffer(output, "utf-8");
-                zlib.gzip(buf, function(_, result) {
-                    gzipCached = result;
-                    res.end(result);
-                });
-            } else {
-                res.end(gzipCached);
-            }
+            var buf = new Buffer(output, "utf-8");
+            zlib.gzip(buf, function(_, result) {
+                res.end(result);
+            });
         } else {
             res.end(output);
         }
diff --git a/lib/connect-utils.js b/lib/connect-utils.js
index 325364a4c..dcc7c440e 100644
--- a/lib/connect-utils.js
+++ b/lib/connect-utils.js
@@ -123,6 +123,7 @@ var connectUtils = {
 
         template = template
             .replace("%config%", JSON.stringify(clientConfig.toJS()))
+            .replace("%options%", JSON.stringify(options))
             .replace("%url%", url);
 
         return template;
diff --git a/lib/hooks.js b/lib/hooks.js
index 1a40fd854..8e97d0558 100644
--- a/lib/hooks.js
+++ b/lib/hooks.js
@@ -13,9 +13,9 @@ module.exports = {
     "client:js": function(hooks, data) {
         var js = snippetUtils.getClientJs(data.port, data.options);
 
-        return hooks.reduce(function(joined, hook) {
-            return joined + hook;
-        }, js);
+        return hooks.reduce(function(acc, hook) {
+            return acc.concat(hook);
+        }, [js]);
     },
     /**
      * @this {BrowserSync}
diff --git a/lib/snippet.js b/lib/snippet.js
index be547dca8..8620bcb46 100644
--- a/lib/snippet.js
+++ b/lib/snippet.js
@@ -91,12 +91,14 @@ var snippetUtils = {
      * @returns {String}
      */
     getClientJs: function(port, options) {
-        var script = options.get("minify") ? "index.min.js" : "index.js";
-        var client = fs.readFileSync(
-            path.join(__dirname, "..", "client", "dist", script),
-            "utf8"
-        );
-        return [connectUtils.socketConnector(options), client].join(";\n");
+        return () => {
+            const script = options.get("minify") ? "index.min.js" : "index.js";
+            const client = fs.readFileSync(
+                path.join(__dirname, "..", "client", "dist", script),
+                "utf8"
+            );
+            return [connectUtils.socketConnector(options), client].join(";\n");
+        }
     }
 };