Refactored path resolution into getExports + added 'resolve.root' set…

…ting. (closes #18)

lib/getExports.js

@@ -5,24 +5,30 @@ var
   Set = require("es6-set"),
   traverse = require("estraverse").traverse,
   parse = require("./parse"),
-  resolve = require("./resolve");
+  resolve = require("./resolve"),
+  isCore = require("resolve").isCore;
 
 var exportCache = new Map();
 
-function ExportMap() {
+function ExportMap(context) {
+  this.context = context;
+
   this.hasDefault = false;
   this.named = new Set();
 
   this.isCommon = false;
   this.errors = [];
 }
 
-ExportMap.get = function (path) {
+ExportMap.get = function (source, context) {
+
+  var path = resolve(source, context);
+  if (path == null) return null;
 
   var exportMap = exportCache.get(path);
   if (exportMap != null) return exportMap;
 
-  exportMap = ExportMap.parse(path);
+  exportMap = ExportMap.parse(path, context);
 
   exportCache.set(path, exportMap);
 
@@ -32,8 +38,14 @@ ExportMap.get = function (path) {
   return exportMap;
 };
 
-ExportMap.parse = function (path) {
-  var m = new ExportMap();
+ExportMap.parse = function (path, context) {
+  var m = new ExportMap(context);
+
+  if (isCore(path)) {
+    // skip parsing, mark as common
+    m.isCommon = true;
+    return m;
+  }
 
   try {
     var ast = parse(path);
@@ -59,19 +71,10 @@ ExportMap.prototype.captureDefault = function (n) {
   this.hasDefault = true;
 };
 
-ExportMap.prototype.captureAll = function (n, path) {
+ExportMap.prototype.captureAll = function (n) {
   if (n.type !== "ExportAllDeclaration") return;
 
-  try {
-    var deepPath = resolve(n.source.value, path);
-  } catch (err) {
-    this.errors.push(err);
-    return;
-  }
-
-  if (deepPath == null) return;
-
-  var remoteMap = ExportMap.get(deepPath);
+  var remoteMap = ExportMap.get(n.source.value, this.context);
   remoteMap.named.forEach(function (name) { this.named.add(name); }.bind(this));
 };
 

lib/resolve.js

@@ -7,20 +7,26 @@ var
 /**
  * resolve
  * @param  {[type]} file       [description]
- * @param  {[type]} path       [description]
- * @param  {[type]} extensions [description]
- * @return {[type]}            [description]
+ * @param  {[type]} p          - path
+ * @return {[type]} - the full module filesystem path
  */
-module.exports = function (p, file) {
+module.exports = function (p, context) {
+  var
+    paths = [],
+    resolveRoot = context.settings["resolve.root"];
+
+
+  if (resolveRoot != null) paths = paths.concat(resolveRoot);
+
   try {
     return resolve.sync(p, {
-      basedir: path.dirname(file)
+      basedir: path.dirname(context.getFilename()),
+      paths: paths
     });
   } catch (err) {
-    if (err.message.indexOf("Cannot find module") === 0) {
+    if (err.message.indexOf("Cannot find module") === 0)
       return null;
-    } else {
-      throw err;
-    }
+
+    throw err;
   }
 };

lib/rules/default.js

@@ -1,32 +1,23 @@
 "use strict";
 
-var
-  resolve = require("../resolve"),
-  getExports = require("../getExports");
+var getExports = require("../getExports");
 
 require("array.prototype.find");
 
 module.exports = function (context) {
   return {
     "ImportDeclaration": function (node) {
-      var path = resolve(node.source.value, context.getFilename());
-      if (path == null) {
-        return;
-      }
-
       var defaultSpecifier = node.specifiers.find(function (n) { return n.type === "ImportDefaultSpecifier"; });
-      if (!defaultSpecifier) {
-        return;
-      }
+      if (!defaultSpecifier) return;
+
+      var imports = getExports(node.source.value, context);
+      if (imports == null) return;
 
-      var imports = getExports(path);
-      if (imports.named.size === 0 && context.options[0] !== "es6-only") {
+      if (imports.named.size === 0 && context.options[0] !== "es6-only")
         return; // ignore for commonjs compatibility
-      }
 
-      if (!imports.hasDefault) {
+      if (!imports.hasDefault)
         context.report(defaultSpecifier, "No default export found in module.");
-      }
     }
   };
 };

lib/rules/named.js

@@ -1,34 +1,28 @@
 "use strict";
 
-var
-  resolve = require("../resolve"),
-  getExports = require("../getExports");
+var getExports = require("../getExports");
 
 module.exports = function (context) {
   return {
     "ImportDeclaration": function (node) {
-      var path = resolve(node.source.value, context.getFilename());
-      if (path == null) {
-        return;
-      }
+      if (!node.specifiers.some(function (im) { return im.type === "ImportSpecifier"; }))
+        return; // no named imports
+
+      var imports = getExports(node.source.value, context);
+      if (imports == null) return;
 
-      var
-        imports = getExports(path),
-        names = imports.named;
+      var names = imports.named;
 
       // if there are no exports, may be a commonjs module.
       // TODO: "interop" mode that attempts to read module.exports, exports member assignments?
-      if (names.size === 0 && !imports.hasDefault && context.options[0] !== "es6-only") {
+      if (names.size === 0 && !imports.hasDefault && context.options[0] !== "es6-only")
         return;
-      }
 
       node.specifiers.forEach(function (im) {
-        if (im.type !== "ImportSpecifier") {
-          return;
-        }
-        if (!names.has(im.imported.name)){
+        if (im.type !== "ImportSpecifier") return;
+
+        if (!names.has(im.imported.name))
           context.report(im.imported, im.imported.name + " not found in '" + node.source.value + "'");
-        }
       });
     }
   };

lib/rules/namespace.js

@@ -2,7 +2,6 @@
 
 var
   Map = require("es6-map"),
-  resolve = require("../resolve"),
   getExports = require("../getExports");
 
 function importDeclaration(context) {
@@ -19,14 +18,12 @@ module.exports = function (context) {
 
       var declaration = importDeclaration(context);
 
-      var path = resolve(declaration.source.value, context.getFilename());
-      if (path == null) return;
+      var imports = getExports(declaration.source.value, context);
+      if (imports == null || imports.isCommon) return;
 
-      var imports = getExports(path);
-      if (imports.isCommon) return;
-
-      if (imports.named.size === 0) context.report(namespace,
-        "No exported names found in module '" + declaration.source.value + "'.");
+      if (imports.named.size === 0)
+        context.report(namespace,
+          "No exported names found in module '" + declaration.source.value + "'.");
 
       namespaces.set(namespace.local.name, imports.named);
     },

lib/rules/no-common.js

@@ -1,20 +1,16 @@
 "use strict";
 
-var
-  resolve = require("../resolve"),
-  getExports = require("../getExports");
+var getExports = require("../getExports");
 
 module.exports = function (context) {
   return {
     "ImportDeclaration": function (node) {
-      var path = resolve(node.source.value, context.getFilename());
-      if (path == null) { return; }
 
-      var imports = getExports(path);
-      if (imports.isCommon) {
-        context.report(node.source, "'" + node.source.value + "' is a CommonJS module.");
-      }
+      var imports = getExports(node.source.value, context);
+      if (imports == null) return;
 
+      if (imports.isCommon)
+        context.report(node.source, "'" + node.source.value + "' is a CommonJS module.");
     }
-  }
+  };
 };

lib/rules/no-errors.js

@@ -1,8 +1,6 @@
 "use strict";
 
-var
-  resolve = require("../resolve"),
-  getExports = require("../getExports");
+var getExports = require("../getExports");
 
 module.exports = function (context) {
   function message(node, errors) {
@@ -16,10 +14,9 @@ module.exports = function (context) {
 
   return {
     "ImportDeclaration": function (node) {
-      var path = resolve(node.source.value, context.getFilename());
-      if (path == null) return;
+      var imports = getExports(node.source.value, context);
+      if (imports == null) return;
 
-      var imports = getExports(path);
       if (imports.errors.length > 0)
         context.report(node.source, message(node, imports.errors));
     }

lib/rules/no-unresolved.js

@@ -10,7 +10,7 @@ var resolve = require("../resolve");
 module.exports = function (context) {
   return {
     "ImportDeclaration": function (node) {
-      if (resolve(node.source.value, context.getFilename()) == null)
+      if (resolve(node.source.value, context) == null)
         context.report(node.source,
           "Unable to resolve path to module '" + node.source.value + "'.");
     }

tests/files/alternate-root/in-alternate-root.js

@@ -0,0 +1 @@
+export const DEEP = "RISING";

tests/lib/rules/no-common.js

@@ -25,6 +25,9 @@ eslintTester.addRuleTest("lib/rules/no-common", {
       errors: [{ message: "'./nested-common' is a CommonJS module."}]}),
 
     test({code: "import {x} from './umd';",
-      errors: [{ message: "'./umd' is a CommonJS module."}]})
+      errors: [{ message: "'./umd' is a CommonJS module."}]}),
+
+    test({code: "import fs from 'fs';",
+      errors: [{ message: "'fs' is a CommonJS module.", type: "Literal"}]})
   ]
 });

tests/lib/rules/no-errors.js

@@ -16,13 +16,6 @@ eslintTester.addRuleTest("lib/rules/no-errors", {
   ],
 
   invalid: [
-    test({code: "import fs from 'fs';",
-      errors: [{
-        message: "Errors encountered while analysing imported module 'fs'.",
-        type: "Literal"}]}),
-    test({code: "import fs from 'fs';",
-      args: [1, "include-messages"],
-      errors: [{type: "Literal"}]}),
     test({code: "import { a } from './test.coffee';",
       errors: [{
         message: "Errors encountered while analysing imported module './test.coffee'.",

tests/lib/rules/no-unresolved.js

@@ -1,5 +1,7 @@
 "use strict";
 
+var path = require("path");
+
 var test = require("../../utils").test;
 
 var linter = require("eslint").linter,
@@ -16,7 +18,11 @@ eslintTester.addRuleTest("lib/rules/no-unresolved", {
     test({
       code: "import {someThing} from './module';"}),
     test({
-      code: "import fs from 'fs';"})
+      code: "import fs from 'fs';"}),
+
+    test({
+      code: "import { DEEP } from 'in-alternate-root';",
+      settings: {"resolve.root": path.join(process.cwd(), "tests", "files", "alternate-root")}})
     ],
 
   invalid: [
@@ -25,6 +31,11 @@ eslintTester.addRuleTest("lib/rules/no-unresolved", {
       errors: [{message: "Unable to resolve path to module './baz'.", type: "Literal"}]}),
     test({
       code: "import bar from './empty-folder';",
-      errors: [{message: "Unable to resolve path to module './empty-folder'.", type: "Literal"}]})
+      errors: [{message: "Unable to resolve path to module './empty-folder'.", type: "Literal"}]}),
+
+    // sanity check that this module is _not_ found without proper settings
+    test({
+      code: "import { DEEP } from 'in-alternate-root';",
+      errors: [{message: "Unable to resolve path to module 'in-alternate-root'.", type: "Literal"}]})
   ]
 });