JS: Add parser for angular expressions

asgerf · asgerf · commit 928a382ad5d3 · 2021-01-18T12:16:13.000Z
diff --git a/javascript/extractor/src/com/semmle/jcorn/AngularExpressionParser.java b/javascript/extractor/src/com/semmle/jcorn/AngularExpressionParser.java
@@ -0,0 +1,45 @@
+package com.semmle.jcorn;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.semmle.js.ast.CallExpression;
+import com.semmle.js.ast.Expression;
+import com.semmle.js.ast.Position;
+import com.semmle.js.ast.SourceLocation;
+
+/**
+ * Parser for Angular template expressions, based on the JS parser with
+ * modified handling of the pipe operator.
+ */
+public class AngularExpressionParser extends Parser {
+  public AngularExpressionParser(String input, int startPos) {
+    super(new Options(), input, startPos);
+  }
+
+  @Override
+  protected Expression buildBinary(
+      int startPos,
+      Position startLoc,
+      Expression left,
+      Expression right,
+      String op,
+      boolean logical) {
+    // Angular pipe expression: `x|f:a` is desugared to `f(x, a)`
+    if (op.equals("|")) {
+      DestructuringErrors refDestructuringErrors = new DestructuringErrors();
+      List<Expression> arguments = new ArrayList<>();
+      arguments.add(left);
+      while (this.type == TokenType.colon) {
+        this.next();
+        int argStartPos = this.pos;
+        Position argStartLocation = this.curPosition();
+        Expression arg = parseMaybeUnary(refDestructuringErrors, false);
+        arguments.add(parseExprOp(arg, argStartPos, argStartLocation, TokenType.plusMin.binop, true));
+      }
+      SourceLocation loc = new SourceLocation(startLoc);
+      return this.finishNode(new CallExpression(loc, right, null, arguments, false, false)); 
+    }
+    return super.buildBinary(startPos, startLoc, left, right, op, logical);
+  }
+}
diff --git a/javascript/extractor/src/com/semmle/jcorn/Parser.java b/javascript/extractor/src/com/semmle/jcorn/Parser.java
@@ -3,9 +3,21 @@
 import static com.semmle.jcorn.Whitespace.isNewLine;
 import static com.semmle.jcorn.Whitespace.lineBreak;
 
+import java.io.File;
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.Stack;
+import java.util.function.Function;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import com.semmle.jcorn.Identifiers.Dialect;
 import com.semmle.jcorn.Options.AllowReserved;
-import com.semmle.jcorn.TokenType.Properties;
 import com.semmle.js.ast.ArrayExpression;
 import com.semmle.js.ast.ArrayPattern;
 import com.semmle.js.ast.ArrowFunctionExpression;
@@ -45,7 +57,6 @@
 import com.semmle.js.ast.IPattern;
 import com.semmle.js.ast.Identifier;
 import com.semmle.js.ast.IfStatement;
-import com.semmle.js.ast.FieldDefinition;
 import com.semmle.js.ast.ImportDeclaration;
 import com.semmle.js.ast.ImportDefaultSpecifier;
 import com.semmle.js.ast.ImportNamespaceSpecifier;
@@ -95,18 +106,6 @@
 import com.semmle.util.exception.CatastrophicError;
 import com.semmle.util.exception.Exceptions;
 import com.semmle.util.io.WholeIO;
-import java.io.File;
-import java.util.ArrayList;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
-import java.util.Stack;
-import java.util.function.Function;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 /**
  * Java port of Acorn.
@@ -1462,7 +1461,7 @@ protected Expression parseExprOp(
     return left;
   }
 
-  private Expression buildBinary(
+  protected Expression buildBinary(
       int startPos,
       Position startLoc,
       Expression left,
