I'm having the same issue. I also tried changing localIdentName=[path][name]-[local]--[hash:base64:5] param to diff combinations like:

localIdentName=[path][name]-[local]--[hash:base64:7]
localIdentName=[name]-[local]--[hash:base64:5]
localIdentName=[name]-[local]--[hash:base64:7]

but to no avail. It creates same classes with same hashes (even with 7).

Btw, #413 also talks about same issue

Same problem here (webpack 2)

I found some workarounds while trying to debug my issue.

This is the code responsible for resolving the localIdentName:

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
var loaderUtils = require("loader-utils");
var path = require("path");

module.exports = function getLocalIdent(loaderContext, localIdentName, localName, options) {
	if(!options.context)
		options.context = loaderContext.options && typeof loaderContext.options.context === "string" ? loaderContext.options.context : loaderContext.context;
	var request = path.relative(options.context, loaderContext.resourcePath);
	options.content = options.hashPrefix + request + "+" + localName;
	localIdentName = localIdentName.replace(/\[local\]/gi, localName);
	var hash = loaderUtils.interpolateName(loaderContext, localIdentName, options);
	return hash.replace(new RegExp("[^a-zA-Z0-9\\-_\u00A0-\uFFFF]", "g"), "-").replace(/^((-?[0-9])|--)/, "_$1");
};

As you can see, even if you set localIdentName=[path][name]-[local]--[hash:base64:7] the [path] will only be evaluated to the filename only (because the context will be the same/current folder) and that will cause the conflict (eg. files can have the same name).

Workaround 1: Add the context option to your css-loader config and point to the root of your project (or whatever makes sense for you). Now the entire path will be used for generating the hash.

Workaround 2: Define your own resolving function by adding getLocalIdent to your css-loader config (check the Readme for that)

(While this works for me, I don't have much experience with css-loader to make a PR or suggest that this should be the default behaviour)

@hugorodrigues thx I will check that solution, we plan to overhaul css-loader in v1.0.0 and address issues like that. Could you post the part of your webpack.config.js with that setup and PR even if for discussion is highly welcome aswell 😛