Merge pull request #12382 from asgerf/js/import-assertion

JS: Support import assertions

Author: asgerf

javascript/extractor/lib/typescript/src/main.ts

@@ -224,6 +224,7 @@ const astProperties: string[] = [
     "argument",
     "argumentExpression",
     "arguments",
+    "assertClause",
     "assertsModifier",
     "asteriskToken",
     "attributes",

javascript/extractor/src/com/semmle/jcorn/ESNextParser.java

@@ -314,7 +314,8 @@ protected ExportDeclaration parseExportRest(SourceLocation exportStart, Set<Stri
         this.parseExportSpecifiersMaybe(specifiers, exports);
       }
       Literal source = (Literal) this.parseExportFrom(specifiers, null, true);
-      return this.finishNode(new ExportNamedDeclaration(exportStart, null, specifiers, source));
+      Expression assertion = this.parseImportOrExportAssertionAndSemicolon();
+      return this.finishNode(new ExportNamedDeclaration(exportStart, null, specifiers, source, assertion));
     }
 
     return super.parseExportRest(exportStart, exports);
@@ -330,7 +331,8 @@ protected ExportDeclaration parseExportAll(
       List<ExportSpecifier> specifiers = CollectionUtil.makeList(nsSpec);
       this.parseExportSpecifiersMaybe(specifiers, exports);
       Literal source = (Literal) this.parseExportFrom(specifiers, null, true);
-      return this.finishNode(new ExportNamedDeclaration(exportStart, null, specifiers, source));
+      Expression assertion = this.parseImportOrExportAssertionAndSemicolon();
+      return this.finishNode(new ExportNamedDeclaration(exportStart, null, specifiers, source, assertion));
     }
 
     return super.parseExportAll(exportStart, starLoc, exports);
@@ -435,8 +437,15 @@ private MetaProperty parseImportMeta(Position loc) {
    */
   private DynamicImport parseDynamicImport(Position startLoc) {
     Expression source = parseMaybeAssign(false, null, null);
+    Expression attributes = null;
+    if (this.eat(TokenType.comma)) {
+      if (this.type != TokenType.parenR) { // Skip if the comma was a trailing comma
+        attributes = this.parseMaybeAssign(false, null, null);
+        this.eat(TokenType.comma); // Allow trailing comma
+      }
+    }
     this.expect(TokenType.parenR);
-    DynamicImport di = this.finishNode(new DynamicImport(new SourceLocation(startLoc), source));
+    DynamicImport di = this.finishNode(new DynamicImport(new SourceLocation(startLoc), source, attributes));
     return di;
   }
 

javascript/extractor/src/com/semmle/jcorn/Parser.java

@@ -1648,13 +1648,13 @@ protected Expression parseExprAtom(DestructuringErrors refDestructuringErrors) {
       return this.finishNode(node);
     } else if (this.type == TokenType.pound) {
       Position startLoc = this.startLoc;
-      // there is only one case where this is valid, and that is "Ergonomic brand checks for Private Fields", i.e. `#name in obj`. 
+      // there is only one case where this is valid, and that is "Ergonomic brand checks for Private Fields", i.e. `#name in obj`.
       Identifier id = parseIdent(true);
       String op = String.valueOf(this.value);
       if (!op.equals("in")) {
         this.unexpected(startLoc);
       }
-      return this.parseExprOp(id, this.start, startLoc, -1, false); 
+      return this.parseExprOp(id, this.start, startLoc, -1, false);
     } else if (this.type == TokenType.name) {
       Position startLoc = this.startLoc;
       Identifier id = this.parseIdent(this.type != TokenType.name);
@@ -2783,7 +2783,7 @@ protected Statement parseBreakContinueStatement(Position startLoc, String keywor
     boolean isBreak = keyword.equals("break");
     this.next();
     Identifier label = null;
-    if (this.eat(TokenType.semi) || this.insertSemicolon()) {
+    if (this.eagerlyTrySemicolon()) {
       label = null;
     } else if (this.type != TokenType.name) {
       this.unexpected();
@@ -2893,6 +2893,15 @@ protected Statement parseIfStatement(Position startLoc) {
         new IfStatement(new SourceLocation(startLoc), test, consequent, alternate));
   }
 
+  /**
+   * Consumes or inserts a semicolon if possible, and returns true if a semicolon was consumed or inserted.
+   *
+   * Returns false if there was no semicolon and insertion was not possible.
+   */
+  protected boolean eagerlyTrySemicolon() {
+    return this.eat(TokenType.semi) || this.insertSemicolon();
+  }
+
   protected ReturnStatement parseReturnStatement(Position startLoc) {
     if (!this.inFunction && !this.options.allowReturnOutsideFunction())
       this.raise(this.start, "'return' outside of function");
@@ -2902,7 +2911,7 @@ protected ReturnStatement parseReturnStatement(Position startLoc) {
     // optional arguments, we eagerly look for a semicolon or the
     // possibility to insert one.
     Expression argument;
-    if (this.eat(TokenType.semi) || this.insertSemicolon()) {
+    if (this.eagerlyTrySemicolon()) {
       argument = null;
     } else {
       argument = this.parseExpression(false, null);
@@ -3404,6 +3413,7 @@ protected ExportDeclaration parseExportRest(SourceLocation loc, Set<String> expo
     Statement declaration;
     List<ExportSpecifier> specifiers;
     Expression source = null;
+    Expression assertion = null;
     if (this.shouldParseExportStatement()) {
       declaration = this.parseStatement(true, false);
       if (declaration == null) return null;
@@ -3419,11 +3429,13 @@ protected ExportDeclaration parseExportRest(SourceLocation loc, Set<String> expo
       declaration = null;
       specifiers = this.parseExportSpecifiers(exports);
       source = parseExportFrom(specifiers, source, false);
+      assertion = parseImportOrExportAssertionAndSemicolon();
     }
     return this.finishNode(
-        new ExportNamedDeclaration(loc, declaration, specifiers, (Literal) source));
+        new ExportNamedDeclaration(loc, declaration, specifiers, (Literal) source, assertion));
   }
 
+  /** Parses the 'from' clause of an export, not including the assertion or semicolon. */
   protected Expression parseExportFrom(
       List<ExportSpecifier> specifiers, Expression source, boolean expectFrom) {
     if (this.eatContextual("from")) {
@@ -3442,14 +3454,14 @@ protected Expression parseExportFrom(
 
       source = null;
     }
-    this.semicolon();
     return source;
   }
 
   protected ExportDeclaration parseExportAll(
       SourceLocation loc, Position starLoc, Set<String> exports) {
     Expression source = parseExportFrom(null, null, true);
-    return this.finishNode(new ExportAllDeclaration(loc, (Literal) source));
+    Expression assertion = parseImportOrExportAssertionAndSemicolon();
+    return this.finishNode(new ExportAllDeclaration(loc, (Literal) source, assertion));
   }
 
   private void checkExport(Set<String> exports, String name, Position pos) {
@@ -3514,6 +3526,16 @@ protected Statement parseImport(Position startLoc) {
     return parseImportRest(loc);
   }
 
+  protected Expression parseImportOrExportAssertionAndSemicolon() {
+    Expression result = null;
+    if (!this.eagerlyTrySemicolon()) {
+      this.expectContextual("assert");
+      result = this.parseObj(false, null);
+      this.semicolon();
+    }
+    return result;
+  }
+
   protected ImportDeclaration parseImportRest(SourceLocation loc) {
     List<ImportSpecifier> specifiers;
     Literal source;
@@ -3527,9 +3549,9 @@ protected ImportDeclaration parseImportRest(SourceLocation loc) {
       if (this.type != TokenType.string) this.unexpected();
       source = (Literal) this.parseExprAtom(null);
     }
-    this.semicolon();
+    Expression assertion = this.parseImportOrExportAssertionAndSemicolon();
     if (specifiers == null) return null;
-    return this.finishNode(new ImportDeclaration(loc, specifiers, source));
+    return this.finishNode(new ImportDeclaration(loc, specifiers, source, assertion));
   }
 
   // Parses a comma-separated list of module imports.

javascript/extractor/src/com/semmle/jcorn/flow/FlowParser.java

@@ -943,10 +943,12 @@ protected ExportDeclaration parseExportRest(SourceLocation loc, Set<String> expo
           // `export type { foo, bar };`
           List<ExportSpecifier> specifiers = this.parseExportSpecifiers(exports);
           this.parseExportFrom(specifiers, null, false);
+          this.parseImportOrExportAssertionAndSemicolon();
           return null;
         } else if (this.eat(TokenType.star)) {
           if (this.eatContextual("as")) this.parseIdent(true);
           this.parseExportFrom(null, null, true);
+          this.parseImportOrExportAssertionAndSemicolon();
           return null;
         } else {
           // `export type Foo = Bar;`

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

@@ -2,16 +2,23 @@
 
 public class DynamicImport extends Expression {
   private final Expression source;
+  private final Expression attributes;
 
-  public DynamicImport(SourceLocation loc, Expression source) {
+  public DynamicImport(SourceLocation loc, Expression source, Expression attributes) {
     super("DynamicImport", loc);
     this.source = source;
+    this.attributes = attributes;
   }
 
   public Expression getSource() {
     return source;
   }
 
+  /** Returns the second "argument" provided to the import, such as <code>{ assert: { type: "json" }}</code>. */
+  public Expression getAttributes() {
+    return attributes;
+  }
+
   @Override
   public <C, R> R accept(Visitor<C, R> v, C c) {
     return v.visit(this, c);

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

@@ -9,16 +9,22 @@
  */
 public class ExportAllDeclaration extends ExportDeclaration {
   private final Literal source;
+  private final Expression assertion;
 
-  public ExportAllDeclaration(SourceLocation loc, Literal source) {
+  public ExportAllDeclaration(SourceLocation loc, Literal source, Expression assertion) {
     super("ExportAllDeclaration", loc);
     this.source = source;
+    this.assertion = assertion;
   }
 
   public Literal getSource() {
     return source;
   }
 
+  public Expression getAssertion() {
+    return assertion;
+  }
+
   @Override
   public <C, R> R accept(Visitor<C, R> v, C c) {
     return v.visit(this, c);

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

@@ -15,20 +15,22 @@ public class ExportNamedDeclaration extends ExportDeclaration {
   private final Statement declaration;
   private final List<ExportSpecifier> specifiers;
   private final Literal source;
+  private final Expression assertion;
   private final boolean hasTypeKeyword;
 
   public ExportNamedDeclaration(
-      SourceLocation loc, Statement declaration, List<ExportSpecifier> specifiers, Literal source) {
-    this(loc, declaration, specifiers, source, false);
+      SourceLocation loc, Statement declaration, List<ExportSpecifier> specifiers, Literal source, Expression assertion) {
+    this(loc, declaration, specifiers, source, assertion, false);
   }
 
   public ExportNamedDeclaration(
       SourceLocation loc, Statement declaration, List<ExportSpecifier> specifiers, Literal source,
-      boolean hasTypeKeyword) {
+      Expression assertion, boolean hasTypeKeyword) {
     super("ExportNamedDeclaration", loc);
     this.declaration = declaration;
     this.specifiers = specifiers;
     this.source = source;
+    this.assertion = assertion;
     this.hasTypeKeyword = hasTypeKeyword;
   }
 
@@ -57,6 +59,11 @@ public <C, R> R accept(Visitor<C, R> v, C c) {
     return v.visit(this, c);
   }
 
+  /** Returns the expression after the <code>assert</code> keyword, if any, such as <code>{ type: "json" }</code>. */
+  public Expression getAssertion() {
+    return assertion;
+  }
+
   /** Returns true if this is an <code>export type</code> declaration. */
   public boolean hasTypeKeyword() {
     return hasTypeKeyword;

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

@@ -23,18 +23,21 @@ public class ImportDeclaration extends Statement implements INodeWithSymbol {
   /** The module from which declarations are imported. */
   private final Literal source;
 
+  private final Expression assertion;
+
   private int symbol = -1;
 
   private boolean hasTypeKeyword;
 
-  public ImportDeclaration(SourceLocation loc, List<ImportSpecifier> specifiers, Literal source) {
-    this(loc, specifiers, source, false);
+  public ImportDeclaration(SourceLocation loc, List<ImportSpecifier> specifiers, Literal source, Expression assertion) {
+    this(loc, specifiers, source, assertion, false);
   }
 
-  public ImportDeclaration(SourceLocation loc, List<ImportSpecifier> specifiers, Literal source, boolean hasTypeKeyword) {
+  public ImportDeclaration(SourceLocation loc, List<ImportSpecifier> specifiers, Literal source, Expression assertion, boolean hasTypeKeyword) {
     super("ImportDeclaration", loc);
     this.specifiers = specifiers;
     this.source = source;
+    this.assertion = assertion;
     this.hasTypeKeyword = hasTypeKeyword;
   }
 
@@ -46,6 +49,11 @@ public List<ImportSpecifier> getSpecifiers() {
     return specifiers;
   }
 
+  /** Returns the expression after the <code>assert</code> keyword, if any, such as <code>{ type: "json" }</code>. */
+  public Expression getAssertion() {
+    return assertion;
+  }
+
   @Override
   public <C, R> R accept(Visitor<C, R> v, C c) {
     return v.visit(this, c);

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

@@ -523,7 +523,7 @@ public MetaProperty visit(MetaProperty nd, Void c) {
 
   @Override
   public ExportAllDeclaration visit(ExportAllDeclaration nd, Void c) {
-    return new ExportAllDeclaration(visit(nd.getLoc()), copy(nd.getSource()));
+    return new ExportAllDeclaration(visit(nd.getLoc()), copy(nd.getSource()), copy(nd.getAssertion()));
   }
 
   @Override
@@ -537,7 +537,8 @@ public ExportNamedDeclaration visit(ExportNamedDeclaration nd, Void c) {
         visit(nd.getLoc()),
         copy(nd.getDeclaration()),
         copy(nd.getSpecifiers()),
-        copy(nd.getSource()));
+        copy(nd.getSource()),
+        copy(nd.getAssertion()));
   }
 
   @Override
@@ -558,7 +559,7 @@ public ExportSpecifier visit(ExportSpecifier nd, Void c) {
   @Override
   public ImportDeclaration visit(ImportDeclaration nd, Void c) {
     return new ImportDeclaration(
-        visit(nd.getLoc()), copy(nd.getSpecifiers()), copy(nd.getSource()));
+        visit(nd.getLoc()), copy(nd.getSpecifiers()), copy(nd.getSource()), copy(nd.getAssertion()), nd.hasTypeKeyword());
   }
 
   @Override
@@ -678,7 +679,7 @@ public INode visit(ExternalModuleReference nd, Void c) {
 
   @Override
   public INode visit(DynamicImport nd, Void c) {
-    return new DynamicImport(visit(nd.getLoc()), copy(nd.getSource()));
+    return new DynamicImport(visit(nd.getLoc()), copy(nd.getSource()), copy(nd.getAttributes()));
   }
 
   @Override

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

@@ -1759,6 +1759,7 @@ public Label visit(MetaProperty nd, Context c) {
     public Label visit(ExportAllDeclaration nd, Context c) {
       Label lbl = super.visit(nd, c);
       visit(nd.getSource(), lbl, 0);
+      visit(nd.getAssertion(), lbl, -10);
       return lbl;
     }
 
@@ -1774,6 +1775,7 @@ public Label visit(ExportNamedDeclaration nd, Context c) {
       Label lbl = super.visit(nd, c);
       visit(nd.getDeclaration(), lbl, -1);
       visit(nd.getSource(), lbl, -2);
+      visit(nd.getAssertion(), lbl, -10);
       IdContext childContext =
           nd.hasSource()
               ? IdContext.LABEL
@@ -1797,6 +1799,7 @@ public Label visit(ExportSpecifier nd, Context c) {
     public Label visit(ImportDeclaration nd, Context c) {
       Label lbl = super.visit(nd, c);
       visit(nd.getSource(), lbl, -1);
+      visit(nd.getAssertion(), lbl, -10);
       IdContext childContext =
           nd.hasTypeKeyword()
               ? IdContext.TYPE_ONLY_IMPORT
@@ -1972,6 +1975,7 @@ public Label visit(ExternalModuleReference nd, Context c) {
     public Label visit(DynamicImport nd, Context c) {
       Label key = super.visit(nd, c);
       visit(nd.getSource(), key, 0);
+      visit(nd.getAttributes(), key, 1);
       return key;
     }