Temp: changes to Module to enable MRVA query

Author: asgerf

javascript/ql/lib/semmle/javascript/Modules.qll

@@ -140,6 +140,13 @@ abstract class Import extends AstNode {
    * Gets the module the path of this import resolves to.
    */
   Module resolveImportedPath() {
+    result.getFile() = this.getEnclosingModule().resolve(this.getImportedPath())
+  }
+
+  /**
+   * Gets the module the path of this import resolves to.
+   */
+  Module resolveImportedPathNew() {
     result.getFile() = PathExprResolver::resolvePathExpr(this.getImportedPath())
   }
 
@@ -169,9 +176,9 @@ abstract class Import extends AstNode {
   }
 
   /**
-   * DEPRECATED. Use `getImportedModule()` instead.
+   * Gets the imported module, as determined by the TypeScript compiler, if any.
    */
-  deprecated Module resolveFromTypeScriptSymbol() {
+  Module resolveFromTypeScriptSymbol() {
     exists(CanonicalName symbol |
       ast_node_symbol(this, symbol) and
       ast_node_symbol(result, symbol)
@@ -193,8 +200,10 @@ abstract class Import extends AstNode {
     then result = this.resolveExternsImport()
     else (
       result = this.resolveAsProvidedModule() or
-      result = this.resolveImportedPath() or
-      result = this.resolveFromTypeRoot()
+      result = this.resolveImportedPathNew() or
+      result = this.resolveFromTypeRoot() or
+      // result = this.resolveFromTypeScriptSymbol() or
+      result = resolveNeighbourPackage(this.getImportedPath().getValue())
     )
   }
 
@@ -203,3 +212,28 @@ abstract class Import extends AstNode {
    */
   abstract DataFlow::Node getImportedModuleNode();
 }
+
+/**
+ * Gets a module imported from another package in the same repository.
+ *
+ * No support for importing from folders inside the other package.
+ */
+Module resolveNeighbourPackage(PathString importPath) {
+  exists(PackageJson json | importPath = json.getPackageName() and result = json.getMainModule())
+  or
+  exists(string package |
+    result.getFile().getParentContainer() = getPackageFolder(package) and
+    importPath = package + "/" + [result.getFile().getBaseName(), result.getFile().getStem()]
+  )
+}
+
+/**
+ * Gets the folder for a package that has name `package` according to a package.json file in the resulting folder.
+ */
+pragma[noinline]
+private Folder getPackageFolder(string package) {
+  exists(PackageJson json |
+    json.getPackageName() = package and
+    result = json.getFile().getParentContainer()
+  )
+}