new config option "absolutePaths", new exposed method "getReplacement", update README

README.md

@@ -99,6 +99,20 @@ relative to the file which is doing the `require` call.  In this case you can do
 This will cause all occurences of `require("d3")` to be replaced with `require("./shims/d3.js")`,
 regardless of where those files are in the directory tree.
 
+Absolute Replacements
+=================
+
+When you specify:
+
+    aliases: {
+        "d3": "./shims/d3.js"
+    },
+    absolutePaths: true
+
+
+This will cause all occurences of `require("d3")` to be replaced with `require("[absolute path to d3.js]")`,
+regardless of where those files are in the directory tree.
+
 Regular Expression Aliasing
 ===========================
 You can use the `replacements` configuration section to create more powerful aliasing.  This is useful if you
@@ -147,29 +161,55 @@ You can tell aliasify to also replace aliases in other functions than `require`.
 node's require function with another one. For example in case of [proxyquireify](https://github.com/thlorenz/proxyquireify) this is very helpful.
 
 ```JavaScript
-    var aliasify = require("aliasify").requireish(["require", "foo", "bar"])
+    var aliasify = require("aliasify");
 ```
 
 with this options:
 
     aliases: {
-            "d3": {"relative": "./shims/d3.js"}
-        }
+            "d3": "./shims/d3.js"
+        },
+    requireish: ["require", "foo", "bar"]
 
 Now any code which tries to `require('d3')` or `foo('d3')` or even `bar('d3')` will end up compiling to:
 
 `require("./shims/d3.js")` respectively `foo("./shims/d3.js")` respectively `bar("./shims/d3.js")`
 
-The argument for `requireish()` can be either a string or an array of strings.
+The argument for `requireish` can be either a string or an array of strings.
 
 A few things to note: first, if you specify `requireish`, you must explicitly list `require` in the list of requireish
 things to transform, or it won't be.
 
 Second, note that aliasify only replaces the first string parameter of the "requireish" function call. All other
-arguments are preserved as they were passed in. (e.g. `require('d3', 'foo')` turns into
+arguments are preserved as they were passed in. (e.g. `require('d3', 'foo')` gets transformed to
 `require('./shims/d3.js', 'foo')`.)  Caution! Do NOT pass in arguments that have circular references. If you need that,
 than just pass in an identifier for the object having circular references!
 
+
+Manually get absolute replacement path
+=====================
+
+You can manually get the absolute path to a replacement from an alias:
+
+```JavaScript
+    var aliasify = require("aliasify");
+
+    var aliasifyConfig = {
+      aliases: {
+                  "d3": "./shims/d3.js"
+              }
+    }
+
+    var path = aliasify.getReplacement("d3", aliasifyConfig);
+```
+
+Now `path` is the absolute path to `d3.js`.
+If no replacement is found the function returns `false`.
+
+Note that the manual method just concatenates `configDir` with the matching entry in `aliases` or `replacement` part from the aliasify config you pass in.
+In order to work properly you have to ensure that this concatenation (through `path.resolve`) makes sense, *e.g.* `configDir = [projectRoot]` and aliases part from the config has entries relative from this `configDir`.
+
+
 Alternatives
 ============
 

src/aliasify.coffee

@@ -40,6 +40,7 @@ makeTransform = (requireAliases) ->
         aliases = opts.config.aliases
         regexps = opts.config.replacements
         verbose = opts.config.verbose
+        absolutePaths = opts.config.absolutePaths
 
         configDir = opts.configData?.configDir or opts.config.configDir or process.cwd()
 
@@ -55,10 +56,11 @@ makeTransform = (requireAliases) ->
                     replacement = replacement.relative
 
                 else if /^\./.test(replacement)
-                    # Resolve the new file relative to the configuration file.
+                    # Resolve the new file relative to the configuration file or system absolute
                     replacement = path.resolve configDir, replacement
-                    fileDir = path.dirname opts.file
-                    replacement = "./#{path.relative fileDir, replacement}"
+                    if !absolutePaths
+                        fileDir = path.dirname opts.file
+                        replacement = "./#{path.relative fileDir, replacement}"
 
                 if verbose
                     console.error "aliasify - #{opts.file}: replacing #{file} with #{replacement} " +
@@ -110,3 +112,15 @@ module.exports = (file, config) ->
 
 module.exports.configure = (config) ->
     return (file) -> module.exports file, config
+
+module.exports.getReplacement = (alias, config) ->
+    if !config then return new Error("Could not find configuration for aliasify")
+    aliases = config.aliases
+    regexps = config.replacements
+
+    replacement = getReplacement alias, aliases, regexps
+    if replacement?
+        configDir = config.configDir or process.cwd()
+        path.resolve configDir, replacement
+    else
+        false

test/test.coffee

@@ -50,7 +50,6 @@ describe "aliasify", ->
             done()
 
     it "should load requireish options from config", (done) ->
-        console.log requireishConfigDir
         process.chdir requireishConfigDir
         jsFile = path.resolve requireishConfigDir, "foobar.js"
         transformTools.runTransform aliasify, jsFile, (err, result) ->
@@ -69,6 +68,15 @@ describe "aliasify", ->
                 _ = require("underscore");
             """)
 
+    it "should allow setting the replacement path absolute", ->
+        absolutePath = path.resolve process.cwd(), './foo/baz.js'
+        runTestWithConfig {aliases: {"d3": "./foo/baz.js"}, absolutePaths: true}
+        .then (result) ->
+            assert.equal Mocha.utils.clean(result), Mocha.utils.clean("""
+                d3 = require('#{absolutePath}');
+                _ = require("underscore");
+            """)
+
     it "should allow removal of requires", ->
         runTestWithConfig {aliases: {"d3": false}}
         .then (result) ->
@@ -359,3 +367,8 @@ describe "aliasify", ->
             assert.equal Mocha.utils.clean(result), Mocha.utils.clean("""
                 var foo = foobar('../foo/foo.js', 'baz', bar, function (){}, {}, []);
             """)
+
+    it "should return the right absolute path through the getReplacement method", ->
+        absolutePath = path.resolve process.cwd(), './foo/baz.js'
+        path = aliasify.getReplacement "d3", {aliases: {"d3": "./foo/baz.js"}}
+        assert.equal Mocha.utils.clean(path), Mocha.utils.clean(absolutePath)