From 69b64cc76530ea038f54bda239b1d271c6a09562 Mon Sep 17 00:00:00 2001
From: theodm <theodm@users.noreply.github.com>
Date: Wed, 4 Jul 2018 10:50:28 +0200
Subject: [PATCH] Fix aliasing of folder relative to project folder (#1485)
 (#1506)

---
 src/Resolver.js                           | 40 ++++++++---------
 test/integration/resolver/nested/index.js |  0
 test/integration/resolver/package.json    |  6 ++-
 test/resolver.js                          | 54 +++++++++++++++++++++++
 4 files changed, 78 insertions(+), 22 deletions(-)
 mode change 100644 => 100755 src/Resolver.js
 create mode 100644 test/integration/resolver/nested/index.js
 mode change 100644 => 100755 test/integration/resolver/package.json

diff --git a/src/Resolver.js b/src/Resolver.js
old mode 100644
new mode 100755
index d8f71c5d585..24834f58d69
--- a/src/Resolver.js
+++ b/src/Resolver.js
@@ -351,14 +351,14 @@ class Resolver {
         filename = './' + filename;
       }
 
-      alias = this.lookupAlias(aliases, filename);
+      alias = this.lookupAlias(aliases, filename, dir);
     } else {
       // It is a node_module. First try the entire filename as a key.
-      alias = aliases[filename];
+      alias = this.lookupAlias(aliases, filename, dir);
       if (alias == null) {
         // If it didn't match, try only the module name.
         let parts = this.getModuleParts(filename);
-        alias = aliases[parts[0]];
+        alias = this.lookupAlias(aliases, parts[0], dir);
         if (typeof alias === 'string') {
           // Append the filename back onto the aliased module.
           alias = path.join(alias, ...parts.slice(1));
@@ -371,32 +371,30 @@ class Resolver {
       return EMPTY_SHIM;
     }
 
-    // If the alias is a relative path, then resolve
-    // relative to the package.json directory.
-    if (alias && alias[0] === '.') {
-      return path.resolve(dir, alias);
-    }
-
-    // Otherwise, assume the alias is a module
     return alias;
   }
 
-  lookupAlias(aliases, filename) {
+  lookupAlias(aliases, filename, dir) {
     // First, try looking up the exact filename
     let alias = aliases[filename];
-    if (alias != null) {
-      return alias;
-    }
-
-    // Otherwise, try replacing glob keys
-    for (let key in aliases) {
-      if (isGlob(key)) {
-        let re = micromatch.makeRe(key, {capture: true});
-        if (re.test(filename)) {
-          return filename.replace(re, aliases[key]);
+    if (alias == null) {
+      // Otherwise, try replacing glob keys
+      for (let key in aliases) {
+        if (isGlob(key)) {
+          let re = micromatch.makeRe(key, {capture: true});
+          if (re.test(filename)) {
+            alias = filename.replace(re, aliases[key]);
+            break;
+          }
         }
       }
     }
+
+    if (typeof alias === 'string') {
+      return this.resolveFilename(alias, dir);
+    }
+
+    return alias;
   }
 
   async findPackage(dir) {
diff --git a/test/integration/resolver/nested/index.js b/test/integration/resolver/nested/index.js
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/test/integration/resolver/package.json b/test/integration/resolver/package.json
old mode 100644
new mode 100755
index 7df4a9bd822..23f96e8842f
--- a/test/integration/resolver/package.json
+++ b/test/integration/resolver/package.json
@@ -4,6 +4,10 @@
   "alias": {
     "aliased": "foo",
     "aliased-file": "./bar.js",
-    "something": "./nested/test.js"
+    "something": "./nested/test.js",
+    "aliasedfolder": "./nested",
+    "aliasedabsolute": "/nested",
+    "foo/bar": "./bar.js",
+    "glob/*/*": "./nested/$2"
   }
 }
diff --git a/test/resolver.js b/test/resolver.js
index 5d36bd739d2..467a569900b 100644
--- a/test/resolver.js
+++ b/test/resolver.js
@@ -367,6 +367,60 @@ describe('resolver', function() {
       assert.equal(resolved.pkg.name, 'resolver');
     });
 
+    it('should apply an alias for a virtual module folder (relative to project dir)', async function() {
+      let resolved = await resolver.resolve(
+        'aliasedfolder/test.js',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'nested', 'test.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
+    it('should apply an alias for a virtual module folder only (relative to project dir)', async function() {
+      let resolved = await resolver.resolve(
+        'aliasedfolder',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'nested', 'index.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
+    it('should apply an alias for a virtual module folder (relative to root dir)', async function() {
+      let resolved = await resolver.resolve(
+        'aliasedabsolute/test.js',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'nested', 'test.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
+    it('should apply an alias for a virtual module folder only (relative to root dir)', async function() {
+      let resolved = await resolver.resolve(
+        'aliasedabsolute',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'nested', 'index.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
+    it('should apply an alias for a virtual module folder sub-path', async function() {
+      let resolved = await resolver.resolve(
+        'foo/bar',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'bar.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
+    it('should apply an alias for a virtual module folder glob sub-path', async function() {
+      let resolved = await resolver.resolve(
+        'glob/bar/test',
+        path.join(rootDir, 'foo.js')
+      );
+      assert.equal(resolved.path, path.join(rootDir, 'nested', 'test.js'));
+      assert.equal(resolved.pkg.name, 'resolver');
+    });
+
     it('should apply an alias for a virtual module', async function() {
       let resolved = await resolver.resolve(
         'something',