add support for type-only import specifiers

Author: erik-krogh

javascript/extractor/src/com/semmle/js/ast/ImportSpecifier.java

@@ -10,15 +10,25 @@
  */
 public class ImportSpecifier extends Expression {
   private final Identifier imported, local;
+  private final boolean isTypeOnly;
 
   public ImportSpecifier(SourceLocation loc, Identifier imported, Identifier local) {
-    this("ImportSpecifier", loc, imported, local);
+    this(loc, imported, local, false);
+  }
+
+  public ImportSpecifier(SourceLocation loc, Identifier imported, Identifier local, boolean isTypeOnly) {
+    this("ImportSpecifier", loc, imported, local, isTypeOnly);
   }
 
   public ImportSpecifier(String type, SourceLocation loc, Identifier imported, Identifier local) {
+    this(type, loc, imported, local, false);
+  }
+
+  private ImportSpecifier(String type, SourceLocation loc, Identifier imported, Identifier local, boolean isTypeOnly) {
     super(type, loc);
     this.imported = imported;
     this.local = local == imported ? new NodeCopier().copy(local) : local;
+    this.isTypeOnly = isTypeOnly;
   }
 
   public Identifier getImported() {
@@ -33,4 +43,8 @@ public Identifier getLocal() {
   public <C, R> R accept(Visitor<C, R> v, C c) {
     return v.visit(this, c);
   }
+
+  public boolean hasTypeKeyword() {
+    return isTypeOnly;
+  }
 }

javascript/extractor/src/com/semmle/js/extractor/ASTExtractor.java

@@ -1806,6 +1806,9 @@ public Label visit(ImportSpecifier nd, Context c) {
       Label lbl = super.visit(nd, c);
       visit(nd.getImported(), lbl, 0, IdContext.LABEL);
       visit(nd.getLocal(), lbl, 1, c.idcontext);
+      if (nd.hasTypeKeyword()) {
+        trapwriter.addTuple("has_type_keyword", lbl);
+      } 
       return lbl;
     }
 

javascript/extractor/src/com/semmle/ts/extractor/TypeScriptASTConverter.java

@@ -1406,7 +1406,8 @@ private Node convertImportSpecifier(JsonObject node, SourceLocation loc) throws
     boolean hasImported = hasChild(node, "propertyName");
     Identifier imported = convertChild(node, hasImported ? "propertyName" : "name");
     Identifier local = convertChild(node, "name");
-    return new ImportSpecifier(loc, imported, local);
+    boolean isTypeOnly = node.get("isTypeOnly").getAsBoolean() == true;
+    return new ImportSpecifier(loc, imported, local, isTypeOnly);
   }
 
   private Node convertImportType(JsonObject node, SourceLocation loc) throws ParseError {

javascript/ql/lib/semmle/javascript/ES2015Modules.qll

@@ -172,6 +172,9 @@ class ImportSpecifier extends Expr, @import_specifier {
   VarDecl getLocal() { result = getChildExpr(1) }
 
   override string getAPrimaryQlClass() { result = "ImportSpecifier" }
+
+  /** Holds if this is declared with the `type` keyword, so only types are imported. */
+  predicate isTypeOnly() { has_type_keyword(this) }
 }
 
 /**

javascript/ql/lib/semmlecode.javascript.dbscheme

@@ -392,7 +392,7 @@ case @expr.kind of
 
 @exportspecifier = @named_export_specifier | @export_default_specifier | @export_namespace_specifier;
 
-@import_or_export_declaration = @import_declaration | @export_declaration;
+@import_or_export_declaration = @import_declaration | @export_declaration | @import_specifier;
 
 @type_assertion = @as_type_assertion | @prefix_type_assertion;
 

javascript/ql/test/library-tests/TypeScript/ImportOwnPackage/TypeNames.expected

@@ -1,8 +1,22 @@
+getTypeString
+| bar/client.ts:9:23:9:27 | Inter | Inter |
+| bar/client.ts:10:12:10:14 | Bar | Bar |
+| foo/index.ts:2:10:2:12 | Bar | Bar |
+| foo/index.ts:7:18:7:22 | Inter | Inter |
+| foo/index.ts:8:10:8:12 | Bar | Bar |
+importSpec
+| false | bar/client.ts:1:10:1:12 | Foo |
+| false | bar/client.ts:7:10:7:20 | Foo as Foo2 |
+| true | bar/client.ts:7:23:7:32 | type Inter |
+| true | bar/client.ts:7:35:7:42 | type Bar |
+#select
 | bar/client.ts:3:5:3:5 | f | my-awesome-package | Foo |
 | bar/client.ts:3:9:3:17 | new Foo() | my-awesome-package | Foo |
 | bar/client.ts:4:5:4:5 | b | my-awesome-package | Bar |
 | bar/client.ts:4:9:4:9 | f | my-awesome-package | Foo |
 | bar/client.ts:4:9:4:15 | f.bar() | my-awesome-package | Bar |
+| bar/client.ts:11:16:11:24 | new Foo() | my-awesome-package | Foo |
+| bar/client.ts:11:16:11:30 | new Foo().bar() | my-awesome-package | Bar |
 | foo/index.ts:1:14:1:16 | Foo | my-awesome-package | Foo |
 | foo/index.ts:2:23:2:31 | new Bar() | my-awesome-package | Bar |
 | foo/index.ts:5:14:5:16 | Bar | my-awesome-package | Bar |

javascript/ql/test/library-tests/TypeScript/ImportOwnPackage/TypeNames.ql

@@ -1,5 +1,11 @@
 import javascript
 
+query string getTypeString(TypeExpr te) { result = te.getType().toString() }
+
+query ImportSpecifier importSpec(boolean typeOnly) {
+  if result.isTypeOnly() then typeOnly = true else typeOnly = false
+}
+
 from Expr e, string mod, string name
 where e.getType().(TypeReference).hasQualifiedName(mod, name)
 select e, mod, name

javascript/ql/test/library-tests/TypeScript/ImportOwnPackage/bar/client.ts

@@ -2,3 +2,12 @@ import { Foo } from "../foo";
 
 let f = new Foo();
 let b = f.bar();
+
+
+import { Foo as Foo2, type Inter, type Bar } from "../foo";
+
+class Impl implements Inter {
+    bar(): Bar {
+        return new Foo().bar();
+    }
+}

javascript/ql/test/library-tests/TypeScript/ImportOwnPackage/foo/index.ts

@@ -3,3 +3,7 @@ export class Foo {
 }
 
 export class Bar {}
+
+export interface Inter {
+  bar(): Bar;
+}