Move option normalization code into dedicated module

webpack-contrib · Dec 27, 2016 · bd0e549 · bd0e549
1 parent d8e1fa9
commit bd0e549
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Showing 2 changed files with 89 additions and 80 deletions.
diff --git a/lib/loader.js b/lib/loader.js
@@ -1,14 +1,11 @@
 "use strict";
 
-const utils = require("loader-utils");
 const sass = require("node-sass");
 const path = require("path");
-const os = require("os");
 const async = require("async");
-const assign = require("object-assign");
 const formatSassError = require("./formatSassError");
-const proxyCustomImporters = require("./proxyCustomImporters");
 const webpackImporter = require("./webpackImporter");
+const normalizeOptions = require("./normalizeOptions");
 const pify = require("pify");
 
 // This queue makes sure node-sass leaves one thread available for executing
@@ -29,12 +26,6 @@ function sassLoader(content) {
     const self = this;
     const resourcePath = this.resourcePath;
 
-    // When files have been imported via the includePaths-option, these files need to be
-    // introduced to webpack in order to make them watchable.
-    function addIncludedFilesToWebpack(includedFiles) {
-        includedFiles.forEach(addNormalizedDependency);
-    }
-
     function addNormalizedDependency(file) {
         // node-sass returns UNIX-style paths
         self.dependency(path.normalize(file));
@@ -46,65 +37,17 @@ function sassLoader(content) {
 
     this.cacheable();
 
-    const sassOptions = getLoaderConfig(this);
-
-    sassOptions.data = sassOptions.data ? (sassOptions.data + os.EOL + content) : content;
-
-    // Skip empty files, otherwise it will stop webpack, see issue #21
-    if (sassOptions.data.trim() === "") {
-        callback(null, content);
-        return;
-    }
-
-    // opt.outputStyle
-    if (!sassOptions.outputStyle && this.minimize) {
-        sassOptions.outputStyle = "compressed";
-    }
-
-    // opt.sourceMap
-    // Not using the `this.sourceMap` flag because css source maps are different
-    // @see https://github.com/webpack/css-loader/pull/40
-    if (sassOptions.sourceMap) {
-        // deliberately overriding the sourceMap option
-        // this value is (currently) ignored by libsass when using the data input instead of file input
-        // however, it is still necessary for correct relative paths in result.map.sources.
-        sassOptions.sourceMap = this.options.context + "/sass.map";
-        sassOptions.omitSourceMapUrl = true;
-
-        // If sourceMapContents option is not set, set it to true otherwise maps will be empty/null
-        // when exported by webpack-extract-text-plugin.
-        if ("sourceMapContents" in sassOptions === false) {
-            sassOptions.sourceMapContents = true;
-        }
-    }
-
-    // indentedSyntax is a boolean flag.
-    const ext = path.extname(resourcePath);
-
-    // If we are compiling sass and indentedSyntax isn't set, automatically set it.
-    if (ext && ext.toLowerCase() === ".sass" && "indentedSyntax" in sassOptions === false) {
-        sassOptions.indentedSyntax = true;
-    } else {
-        sassOptions.indentedSyntax = Boolean(sassOptions.indentedSyntax);
-    }
-
-    // Allow passing custom importers to `node-sass`. Accepts `Function` or an array of `Function`s.
-    sassOptions.importer = sassOptions.importer ? proxyCustomImporters(sassOptions.importer, resourcePath) : [];
-    sassOptions.importer.push(webpackImporter(
-        this.resourcePath,
+    const options = normalizeOptions(this, content, webpackImporter(
+        resourcePath,
         pify(this.resolve.bind(this)),
         addNormalizedDependency
     ));
 
-    // `node-sass` uses `includePaths` to resolve `@import` paths. Append the currently processed file.
-    sassOptions.includePaths = sassOptions.includePaths ? [].concat(sassOptions.includePaths) : [];
-    sassOptions.includePaths.push(path.dirname(resourcePath));
-
     // start the actual rendering
-    asyncSassJobQueue.push(sassOptions, (err, result) => {
+    asyncSassJobQueue.push(options, (err, result) => {
         if (err) {
             formatSassError(err, this.resourcePath);
-            err.file && self.dependency(err.file);
+            err.file && this.dependency(err.file);
             callback(err);
             return;
         }
@@ -120,26 +63,9 @@ function sassLoader(content) {
             result.map = null;
         }
 
-        addIncludedFilesToWebpack(result.stats.includedFiles);
+        result.stats.includedFiles.forEach(addNormalizedDependency);
         callback(null, result.css.toString(), result.map);
     });
 }
 
-/**
- * Check the loader query and webpack config for loader options. If an option is defined in both places,
- * the loader query takes precedence.
- *
- * @param {LoaderContext} loaderContext
- * @returns {Object}
- */
-function getLoaderConfig(loaderContext) {
-    const query = utils.parseQuery(loaderContext.query);
-    const configKey = query.config || "sassLoader";
-    const config = loaderContext.options[configKey] || {};
-
-    delete query.config;
-
-    return assign({}, config, query);
-}
-
 module.exports = sassLoader;
diff --git a/lib/normalizeOptions.js b/lib/normalizeOptions.js
@@ -0,0 +1,83 @@
+"use strict";
+
+const os = require("os");
+const utils = require("loader-utils");
+const assign = require("object-assign");
+const path = require("path");
+const proxyCustomImporters = require("./proxyCustomImporters");
+
+/**
+ * Derives the sass options from the loader context and normalizes its values with sane defaults.
+ *
+ * @param {LoaderContext} loaderContext
+ * @param {string} content
+ * @param {Function} webpackImporter
+ * @returns {Object}
+ */
+function normalizeOptions(loaderContext, content, webpackImporter) {
+    const options = getLoaderOptions(loaderContext);
+    const resourcePath = loaderContext.resourcePath;
+
+    options.data = options.data ? (options.data + os.EOL + content) : content;
+
+    // opt.outputStyle
+    if (!options.outputStyle && loaderContext.minimize) {
+        options.outputStyle = "compressed";
+    }
+
+    // opt.sourceMap
+    // Not using the `this.sourceMap` flag because css source maps are different
+    // @see https://github.com/webpack/css-loader/pull/40
+    if (options.sourceMap) {
+        // deliberately overriding the sourceMap option
+        // this value is (currently) ignored by libsass when using the data input instead of file input
+        // however, it is still necessary for correct relative paths in result.map.sources.
+        options.sourceMap = loaderContext.options.context + "/sass.map";
+        options.omitSourceMapUrl = true;
+
+        // If sourceMapContents option is not set, set it to true otherwise maps will be empty/null
+        // when exported by webpack-extract-text-plugin.
+        if ("sourceMapContents" in options === false) {
+            options.sourceMapContents = true;
+        }
+    }
+
+    // indentedSyntax is a boolean flag.
+    const ext = path.extname(resourcePath);
+
+    // If we are compiling sass and indentedSyntax isn't set, automatically set it.
+    if (ext && ext.toLowerCase() === ".sass" && "indentedSyntax" in options === false) {
+        options.indentedSyntax = true;
+    } else {
+        options.indentedSyntax = Boolean(options.indentedSyntax);
+    }
+
+    // Allow passing custom importers to `node-sass`. Accepts `Function` or an array of `Function`s.
+    options.importer = options.importer ? proxyCustomImporters(options.importer, resourcePath) : [];
+    options.importer.push(webpackImporter);
+
+    // `node-sass` uses `includePaths` to resolve `@import` paths. Append the currently processed file.
+    options.includePaths = options.includePaths ? [].concat(options.includePaths) : [];
+    options.includePaths.push(path.dirname(resourcePath));
+
+    return options;
+}
+
+/**
+ * Check the loader query and webpack config for loader options. If an option is defined in both places,
+ * the loader query takes precedence.
+ *
+ * @param {LoaderContext} loaderContext
+ * @returns {Object}
+ */
+function getLoaderOptions(loaderContext) {
+    const query = utils.parseQuery(loaderContext.query);
+    const configKey = query.config || "sassLoader";
+    const config = loaderContext.options[configKey] || {};
+
+    delete query.config;
+
+    return assign({}, config, query);
+}
+
+module.exports = normalizeOptions;